Opinion poll
Encyclopedia
An opinion poll, sometimes simply referred to as a poll is a survey
of public opinion
from a particular sample
. Opinion polls are usually designed to represent the opinions of a population by conducting a series of questions and then extrapolating generalities in ratio or within confidence intervals.
conducted by The Harrisburg Pennsylvanian in 1824
, showing Andrew Jackson
, who actually won the popular vote in the real election, leading John Quincy Adams
by 335 votes to 169 in the contest for the United States Presidency. Such straw votes gradually became more popular, but they remained local, usually city-wide phenomena. In 1916, the Literary Digest
embarked on a national survey (partly as a circulation-raising exercise) and correctly predicted Woodrow Wilson
's election as president. Mailing out millions of postcard
s and simply counting the returns, the Digest correctly called the following four presidential elections.
In 1936
however the Digest came unstuck. Its 2.3 million "voters" constituted a huge sample; however they were generally more affluent Americans who tended to have Republican sympathies. The Literary Digest was ignorant of this new bias. The week before election day, it reported that Alf Landon
was far more popular than Franklin D. Roosevelt
. At the same time, George Gallup
conducted a far smaller, but more scientifically-based survey, in which he polled a demographically representative sample. Gallup correctly predicted Roosevelt's landslide victory. The Literary Digest soon went out of business, while polling started to take off.
Elmo Roper
was another American pioneer in political forecasting using scientific polls. He predicted the reelection of President Franklin D. Roosevelt three times, in 1936, 1940, and 1944. Louis Harris
had been in the field of public opinion since 1947 when he joined the Elmo Roper firm, then later became partner.
Gallup
launched a subsidiary in the United Kingdom
, where it correctly predicted Labour's
victory in the 1945 general election
, in contrast with virtually all other commentators, who expected a victory for the Conservative Party
, led by Winston Churchill
.
By the 1950s, various types of polling had spread to most democracies. In (post Saddam Hussein
era) Iraq
, surveys conducted soon after the 2003 war aimed to measure the feelings of Iraqi citizens regarding Saddam Hussein
, post-war conditions, and the presence of US forces.
, YouGov
and Zogby
use Internet
surveys, where a sample is drawn from a large panel of volunteers, and the results are weighed to reflect the demographics of the population of interest. In contrast, popular web polls draw on whoever wishes to participate, rather than a scientific sample of the population, and are therefore not generally considered professional.
A benchmark poll serves a number of purposes for a campaign, whether it is a political campaign or some other type of campaign. First, it gives the candidate a picture of where they stand with the electorate before any campaigning takes place. If the poll is done prior to announcing for office the candidate may use the poll to decide whether or not they should even run for office. Secondly, it shows them where their weaknesses and strengths are in two main areas. The first is the electorate. A benchmark poll shows them what types of voters they are sure to win, those who they are sure to lose, and everyone in-between those two extremes. This lets the campaign know which voters are persuadable so they can spend their limited resources in the most effective manner. Second, it can give them an idea of what messages, ideas, or slogans are the strongest with the electorate.
Brushfire polls are used for a number of purposes. First, it lets the candidate know if they have made any progress on the ballot, how much progress has been made, and in what demographics they have been making or losing ground. Secondly, it is a way for the campaign to test a variety of messages, both positive and negative, on themselves and their opponent(s). This lets the campaign know what messages work best with certain demographics and what messages should be avoided. Campaigns often use these polls to test possible attack messages that their opponent may use and potential responses to those attacks. The campaign can then spend some time preparing an effective response to any likely attacks. Thirdly, this kind of poll can be used by candidates or political parties to convince primary challengers to drop out of a race and support a stronger candidate.
A key benefit of tracking polls is that the trend of a tracking poll (the change over time) corrects for bias: regardless of whether a poll consistently over or underestimates opinion, the trend correctly reflects increases or decreases .
A caution is that estimating the trend is more difficult and error-prone than estimating the level – intuitively, if one estimates the change, the difference between two numbers X and Y, then one has to contend with the error in both X and Y – it is not enough to simply take the difference, as the change may be random noise. For details, see t-test. A rough guide is that if the change in measurement falls outside the margin of error, it is worth attention.
which reflects the effects of chance and uncertainty in the sampling process. The uncertainty is often expressed as a margin of error
. The margin of error is usually defined as the radius of a confidence interval for a particular statistic from a survey. One example is the percent of people who prefer product A versus product B. When a single, global margin of error is reported for a survey, it refers to the maximum margin of error for all reported percentages using the full sample from the survey. If the statistic is a percentage, this maximum margin of error can be calculated as the radius of the confidence interval for a reported percentage of 50%. Others suggest that a poll with a random sample of 1,000 people has margin of sampling error of 3% for the estimated percentage of the whole population.
A 3% margin of error means that if the same procedure is used a large number of times, 95% of the time the true population average will be within the 95% confidence interval of the sample estimate plus or minus 3%. The margin of error can be reduced by using a larger sample, however if a pollster wishes to reduce the margin of error to 1% they would need a sample of around 10,000 people. In practice, pollsters need to balance the cost of a large sample against the reduction in sampling error and a sample size of around 500–1,000 is a typical compromise for political polls. (Note that to get complete responses it may be necessary to include thousands of additional participators.)
Another way to reduce the margin of error is to rely on poll average
s. This makes the assumption that the procedure is similar enough between many different polls and uses the sample size of each poll to create a polling average. An example of a polling average can be found here: 2008 Presidential Election polling average. Another source of error stems from faulty demographic models by pollsters who weigh their samples by particular variables such as party identification in an election. For example, if you assume that the breakdown of the US population by party identification has not changed since the previous presidential election, you may underestimate a victory or a defeat of a particular party candidate that saw a surge or decline in its party registration relative to the previous presidential election cycle.
Over time, a number of theories and mechanisms have been offered to explain erroneous polling results. Some of these reflect errors on the part of the pollsters; many of them are statistical in nature. Others blame the respondents for not giving candid answers (e.g., the Bradley effect
, the Shy Tory Factor
); these can be more controversial.
. Because of this selection bias
, the characteristics of those who agree to be interviewed may be markedly different from those who decline. That is, the actual sample is a biased version of the universe the pollster wants to analyze. In these cases, bias introduces new errors, one way or the other, that are in addition to errors caused by sample size. Error due to bias does not become smaller with larger sample sizes, because taking a larger sample size simply repeats the same mistake on a larger scale. If the people who refuse to answer, or are never reached, have the same characteristics as the people who do answer, then the final results should be unbiased. If the people who do not answer have different opinions then there is bias in the results. In terms of election polls, studies suggest that bias effects are small, but each polling firm has its own techniques for adjusting weights to minimize selection bias.
, where the answers given by respondents do not reflect their true beliefs. This may be deliberately engineered by unscrupulous pollsters in order to generate a certain result or please their clients, but more often is a result of the detailed wording or ordering of questions (see below). Respondents may deliberately try to manipulate the outcome of a poll by e.g. advocating a more extreme position than they actually hold in order to boost their side of the argument or give rapid and ill-considered answers in order to hasten the end of their questioning. Respondents may also feel under social pressure not to give an unpopular answer. For example, respondents might be unwilling to admit to unpopular attitudes like racism
or sexism
, and thus polls might not reflect the true incidence of these attitudes in the population. In American political parlance, this phenomenon is often referred to as the Bradley Effect
. If the results of surveys are widely publicized this effect may be magnified - a phenomenon commonly referred to as the spiral of silence
.
A common technique to control for this bias is to rotate the order in which questions are asked. Many pollsters also split-sample. This involves having two different versions of a question, with each version presented to half the respondents.
The most effective controls, used by attitude
researchers, are:
These controls are not widely used in the polling industry .
In some places many people have only mobile telephones. Because pollsters cannot call mobile phones (it is unlawful in the United States to make unsolicited calls to phones where the phone's owner may be charged simply for taking a call), these individuals will never be included in the polling sample. If the subset of the population without cell phones differs markedly from the rest of the population, these differences can skew the results of the poll. Polling organizations have developed many weighting techniques to help overcome these deficiencies, to varying degrees of success. Studies of mobile phone users by the Pew Research Center in the US concluded that "cell-only respondents are different from landline respondents in important ways, (but) they were neither numerous enough nor different enough on the questions we examined to produce a significant change in overall general population survey estimates when included with the landline samples and weighted according to US Census parameters on basic demographic characteristics."
This issue was first identified in 2004, but came to prominence only during the 2008 US presidential election
. In previous elections, the proportion of the general population using cell phones was small, but as this proportion has increased, the worry is that polling only landlines is no longer representative of the general population. In 2003, a 2.9% of households were wireless (cellphones only) compared to 12.8 in 2006. This results in "coverage error". Many polling organisations select their sample by dialling random telephone numbers; however, there is a clear tendency for polls which included mobile phones in their sample to show a much larger lead for Obama
than polls that did not.
The potential sources of bias are:
Some polling companies have attempted to get around that problem by including a "cellphone supplement". There are a number of problems with including cellphones in a telephone poll:
An oft-quoted example of opinion polls succumbing to errors was the UK General Election of 1992. Despite the polling organizations using different methodologies virtually all the polls in the lead up to the vote, and to a lesser extent exit poll
s taken on voting day, showed a lead for the opposition Labour party but the actual vote gave a clear victory to the ruling Conservative party.
In their deliberations after this embarrassment the pollsters advanced several ideas to account for their errors, including:
Late swing
: Voters who changed their minds shortly before voting tended to favour the Conservatives, so the error was not as great as it first appeared.
Nonresponse bias : Conservative voters were less likely to participate in surveys than in the past and were thus under-represented.
The Shy Tory Factor
: The Conservatives had suffered a sustained period of unpopularity as a result of economic difficulties and a series of minor scandals, leading to a spiral of silence
in which some Conservative supporters were reluctant to disclose their sincere intentions to pollsters.
The relative importance of these factors was, and remains, a matter of controversy, but since then the polling organizations have adjusted their methodologies and have achieved more accurate results in subsequent elections.
the most notable companies are:
In Brazil
the most notable companies are:
In Canada
the most notable companies are:
In Egypt
, the most notable polling organization is
In Germany
, notable polling organizations are
In Jordan
the dominant organization is:
In Iran
, some notable polling organisations include:
In New Zealand
, some notable polling organisations include:
In Nigeria
the most notable polling organisation is:
In South Africa
, some notable polling organisations include:
In Ukraine
, the most notable pollsters are:
In the United Kingdom
, the most notable pollsters are:
In the United States
, some notable companies include:
In Spain
:
All the major television network
s, alone or in conjunction with the largest newspapers or magazines, in virtually every country with elections, operate their own versions of polling operations, in collaboration or independently through various applications. One of the applications can be found on Facebook
Several organizations try to monitor the behavior of polling firms and the use of polling and statistical data, including the Pew Research Center
and, in Canada, the Laurier Institute for the Study of Public Opinion and Policy.
was the prediction that Thomas Dewey
would defeat Harry S. Truman
in the 1948 US presidential election. Major polling organizations, including Gallup and Roper, indicated a landslide victory for Dewey.
In the United Kingdom, most polls failed to predict the Conservative election victories of 1970
and 1992
, and Labour's victory in 1974
. However, their figures at other elections have been generally accurate.
, Peter Hitchens
asserts that opinion polls are actually a device for influencing public opinion. The various theories about how this happens can be split into two groups: bandwagon/underdog effects, and strategic ("tactical") voting.
A bandwagon effect
occurs when the poll prompts voters to back the candidate shown to be winning in the poll. The idea that voters are susceptible to such effects is old, stemming at least from 1884; William Safire
reported that the term was first used in a political cartoon in the magazine Puck
in that year. It has also remained persistent in spite of a lack of empirical corroboration until the late 20th century. George Gallup
spent much effort in vain trying to discredit this theory in his time by presenting empirical research. A recent meta-study of scientific research on this topic indicates that from the 1980s onward the Bandwagon effect is found more often by researchers.
The opposite of the bandwagon effect is the underdog
effect. It is often mentioned in the media. This occurs when people vote, out of sympathy, for the party perceived to be "losing" the elections. There is less empirical evidence for the existence of this effect than there is for the existence of the bandwagon effect.
The second category of theories on how polls directly affect voting is called strategic or tactical voting
. This theory is based on the idea that voters view the act of voting as a means of selecting a government. Thus they will sometimes not choose the candidate they prefer on ground of ideology or sympathy, but another, less-preferred, candidate from strategic considerations. An example can be found in the United Kingdom general election, 1997
. As he was then a Cabinet Minister, Michael Portillo
's constituency of Enfield Southgate was believed to be a safe seat
but opinion polls showed the Labour
candidate Stephen Twigg
steadily gaining support, which may have prompted undecided voters or supporters of other parties to support Twigg in order to remove Portillo. Another example is the boomerang effect where the likely supporters of the candidate shown to be winning feel that chances are slim and that their vote is not required, thus allowing another candidate to win.
In addition, Mark Pickup in Cameron Anderson and Laura Stephenson's "Voting Behaviour in Canada" outlines three additional "behavioural" responses that voters may exhibit when faced with polling data.
The first is known as a "cue taking" effect which holds that poll data is used as a "proxy" for information about the candidates or parties. Cue taking is "based on the psychological phenomenon of using heuristics to simplify a complex decision" (243)
The second, first described by Petty and Cacioppo (1996) is known as "cognitive response" theory. This theory asserts that a voter's response to a poll may not line with their initial conception of the electoral reality. In response, the voter is likely to generate a "mental list" in which they create reasons for a party's loss or gain in the polls. This can reinforce or change their opinion of the candidate and thus affect voting behaviour.
Third, the final possibility is a "behavioural response" which is similar to a cognitive response. The only salient difference is that a voter will go and seek new information to form their "mental list," thus becoming more informed of the election. This may then affect voting behaviour.
These effects indicate how opinion polls can directly affect political choices of the electorate. But directly or indirectly, other effects can be surveyed and analyzed on all political parties. The form of media framing
and party ideology shifts must also be taken under consideration. Opinion polling in some instances is a measure of cognitive bias, which is variably considered and handled appropriately in its various applications.
's 1976 presidential campaign
, "It's no longer necessary for a political candidate to guess what an audience thinks. He can [find out] with a nightly tracking poll. So it's no longer likely that political leaders are going to lead. Instead, they're going to follow."
However, most western democratic nations don't support the entire prohibition of the publication of pre-election opinion polls; most of them have no regulation and some only prohibit it in the final days or hours until the relevant poll closes. A survey by Canada's Royal Commission on Electoral Reform reported that the prohibition period of publication of the survey results largely differed in different countries. Out of the 20 countries examined, three prohibit the publication during the entire period of campaigns, while others prohibit it for a shorter term such as the polling period or the final 48 hours before a poll closes.
Additional Sources
Statistical survey
Survey methodology is the field that studies surveys, that is, the sample of individuals from a population with a view towards making statistical inferences about the population using the sample. Polls about public opinion, such as political beliefs, are reported in the news media in democracies....
of public opinion
Public opinion
Public opinion is the aggregate of individual attitudes or beliefs held by the adult population. Public opinion can also be defined as the complex collection of opinions of many different people and the sum of all their views....
from a particular sample
Sampling (statistics)
In statistics and survey methodology, sampling is concerned with the selection of a subset of individuals from within a population to estimate characteristics of the whole population....
. Opinion polls are usually designed to represent the opinions of a population by conducting a series of questions and then extrapolating generalities in ratio or within confidence intervals.
History
The first known example of an opinion poll was a local straw pollStraw poll
A straw poll or straw vote is a vote with nonbinding results. Straw polls provide dialogue among movements within large groups, reflecting trends like organization and motivation...
conducted by The Harrisburg Pennsylvanian in 1824
United States presidential election, 1824
In the United States presidential election of 1824, John Quincy Adams was elected President on February 9, 1825, after the election was decided by the House of Representatives. The previous years had seen a one-party government in the United States, as the Federalist Party had dissolved, leaving...
, showing Andrew Jackson
Andrew Jackson
Andrew Jackson was the seventh President of the United States . Based in frontier Tennessee, Jackson was a politician and army general who defeated the Creek Indians at the Battle of Horseshoe Bend , and the British at the Battle of New Orleans...
, who actually won the popular vote in the real election, leading John Quincy Adams
John Quincy Adams
John Quincy Adams was the sixth President of the United States . He served as an American diplomat, Senator, and Congressional representative. He was a member of the Federalist, Democratic-Republican, National Republican, and later Anti-Masonic and Whig parties. Adams was the son of former...
by 335 votes to 169 in the contest for the United States Presidency. Such straw votes gradually became more popular, but they remained local, usually city-wide phenomena. In 1916, the Literary Digest
Literary Digest
The Literary Digest was an influential general interest weekly magazine published by Funk & Wagnalls. Founded by Isaac Kaufmann Funk in 1890, it eventually merged with two similar weekly magazines, Public Opinion and Current Opinion.-History:...
embarked on a national survey (partly as a circulation-raising exercise) and correctly predicted Woodrow Wilson
Woodrow Wilson
Thomas Woodrow Wilson was the 28th President of the United States, from 1913 to 1921. A leader of the Progressive Movement, he served as President of Princeton University from 1902 to 1910, and then as the Governor of New Jersey from 1911 to 1913...
's election as president. Mailing out millions of postcard
Postcard
A postcard or post card is a rectangular piece of thick paper or thin cardboard intended for writing and mailing without an envelope....
s and simply counting the returns, the Digest correctly called the following four presidential elections.
In 1936
United States presidential election, 1936
The United States presidential election of 1936 was the most lopsided presidential election in the history of the United States in terms of electoral votes. In terms of the popular vote, it was the third biggest victory since the election of 1820, which was not seriously contested.The election took...
however the Digest came unstuck. Its 2.3 million "voters" constituted a huge sample; however they were generally more affluent Americans who tended to have Republican sympathies. The Literary Digest was ignorant of this new bias. The week before election day, it reported that Alf Landon
Alf Landon
Alfred Mossman "Alf" Landon was an American Republican politician, who served as the 26th Governor of Kansas from 1933–1937. He was best known for being the Republican Party's nominee for President of the United States, defeated in a landslide by Franklin D...
was far more popular than Franklin D. Roosevelt
Franklin D. Roosevelt
Franklin Delano Roosevelt , also known by his initials, FDR, was the 32nd President of the United States and a central figure in world events during the mid-20th century, leading the United States during a time of worldwide economic crisis and world war...
. At the same time, George Gallup
George Gallup
George Horace Gallup was an American pioneer of survey sampling techniques and inventor of the Gallup poll, a successful statistical method of survey sampling for measuring public opinion.-Biography:...
conducted a far smaller, but more scientifically-based survey, in which he polled a demographically representative sample. Gallup correctly predicted Roosevelt's landslide victory. The Literary Digest soon went out of business, while polling started to take off.
Elmo Roper
Elmo Roper
Elmo Burns Roper, Jr. was a pollster known for his pioneering work in market research and opinion polling. In 1934, he cofounded Cherington, Wood, and Roper, a marketing research firm. When that partnership fell apart, he founded his own research company, Elmo Roper, Inc...
was another American pioneer in political forecasting using scientific polls. He predicted the reelection of President Franklin D. Roosevelt three times, in 1936, 1940, and 1944. Louis Harris
Louis Harris
Louis Harris is an American opinion polling entrepreneur, journalist, and author. He ran one of the best-known polling organizations of his time, Louis Harris and Associates, which conducted the Harris Poll.-Life and career:...
had been in the field of public opinion since 1947 when he joined the Elmo Roper firm, then later became partner.
Gallup
The Gallup Organization
The Gallup Organization, is primarily a research-based performance-management consulting company. Some of Gallup's key practice areas are - Employee Engagement, Customer Engagement and Well-Being. Gallup has over 40 offices in 27 countries. World headquarters are in Washington, D.C. Operational...
launched a subsidiary in the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, where it correctly predicted Labour's
Labour Party (UK)
The Labour Party is a centre-left democratic socialist party in the United Kingdom. It surpassed the Liberal Party in general elections during the early 1920s, forming minority governments under Ramsay MacDonald in 1924 and 1929-1931. The party was in a wartime coalition from 1940 to 1945, after...
victory in the 1945 general election
United Kingdom general election, 1945
The United Kingdom general election of 1945 was a general election held on 5 July 1945, with polls in some constituencies delayed until 12 July and in Nelson and Colne until 19 July, due to local wakes weeks. The results were counted and declared on 26 July, due in part to the time it took to...
, in contrast with virtually all other commentators, who expected a victory for the Conservative Party
Conservative Party (UK)
The Conservative Party, formally the Conservative and Unionist Party, is a centre-right political party in the United Kingdom that adheres to the philosophies of conservatism and British unionism. It is the largest political party in the UK, and is currently the largest single party in the House...
, led by Winston Churchill
Winston Churchill
Sir Winston Leonard Spencer-Churchill, was a predominantly Conservative British politician and statesman known for his leadership of the United Kingdom during the Second World War. He is widely regarded as one of the greatest wartime leaders of the century and served as Prime Minister twice...
.
By the 1950s, various types of polling had spread to most democracies. In (post Saddam Hussein
Saddam Hussein
Saddam Hussein Abd al-Majid al-Tikriti was the fifth President of Iraq, serving in this capacity from 16 July 1979 until 9 April 2003...
era) Iraq
Iraq
Iraq ; officially the Republic of Iraq is a country in Western Asia spanning most of the northwestern end of the Zagros mountain range, the eastern part of the Syrian Desert and the northern part of the Arabian Desert....
, surveys conducted soon after the 2003 war aimed to measure the feelings of Iraqi citizens regarding Saddam Hussein
Saddam Hussein
Saddam Hussein Abd al-Majid al-Tikriti was the fifth President of Iraq, serving in this capacity from 16 July 1979 until 9 April 2003...
, post-war conditions, and the presence of US forces.
Sample and polling methods
Opinion polls for many years were maintained through telecommunications or in person-to-person contact. Methods and techniques vary, though they are widely accepted in most areas. Verbal, ballot, and processed types can be conducted efficiently, contrasted with other types of surveys, systematics, and complicated matrices beyond previous orthodox procedures. Opinion polling developed into popular applications through popular thought, although response rates for some surveys declined. Also, the following has also led to differentiating results: Some polling organizations, such as Angus Reid StrategiesAngus Reid Strategies
Angus Reid Public Opinion is an international public affairs practice. It was established in 2006 under the name Angus Reid Strategies by Dr Angus Reid, a Canadian sociologist who founded his first research company in 1979. Reid sold the Angus Reid Group to Paris-based Ipsos SA in 2000...
, YouGov
YouGov
YouGov, formerly known as PollingPoint in the United States, is an international internet-based market research firm launched in the UK in May 2000 by Stephan Shakespeare, now Chief Executive Officer, and Nadhim Zahawi...
and Zogby
Zogby International
IBOPE Zogby International is an international market research, opinion polling firm founded in 1984 by John Zogby. The company polls and consults for a wide spectrum of business media, government, and political groups, and conducts public opinion research in more than 70 countries...
use Internet
Internet
The Internet is a global system of interconnected computer networks that use the standard Internet protocol suite to serve billions of users worldwide...
surveys, where a sample is drawn from a large panel of volunteers, and the results are weighed to reflect the demographics of the population of interest. In contrast, popular web polls draw on whoever wishes to participate, rather than a scientific sample of the population, and are therefore not generally considered professional.
Benchmark polls
A benchmark poll is generally the first poll taken in a campaign. It is often taken before a candidate announces their bid for office but sometimes it happens immediately following that announcement after they have had some opportunity to raise funds. This is generally a short and simple survey of likely voters.A benchmark poll serves a number of purposes for a campaign, whether it is a political campaign or some other type of campaign. First, it gives the candidate a picture of where they stand with the electorate before any campaigning takes place. If the poll is done prior to announcing for office the candidate may use the poll to decide whether or not they should even run for office. Secondly, it shows them where their weaknesses and strengths are in two main areas. The first is the electorate. A benchmark poll shows them what types of voters they are sure to win, those who they are sure to lose, and everyone in-between those two extremes. This lets the campaign know which voters are persuadable so they can spend their limited resources in the most effective manner. Second, it can give them an idea of what messages, ideas, or slogans are the strongest with the electorate.
Brushfire polls
Brushfire Polls are polls taken during the period between the Benchmark Poll and Tracking Polls. The number of Brushfire Polls taken by a campaign is determined by how competitive the race is and how much money the campaign has to spend. These polls usually focus on likely voters and the length of the survey varies on the number of messages being tested.Brushfire polls are used for a number of purposes. First, it lets the candidate know if they have made any progress on the ballot, how much progress has been made, and in what demographics they have been making or losing ground. Secondly, it is a way for the campaign to test a variety of messages, both positive and negative, on themselves and their opponent(s). This lets the campaign know what messages work best with certain demographics and what messages should be avoided. Campaigns often use these polls to test possible attack messages that their opponent may use and potential responses to those attacks. The campaign can then spend some time preparing an effective response to any likely attacks. Thirdly, this kind of poll can be used by candidates or political parties to convince primary challengers to drop out of a race and support a stronger candidate.
Tracking polls
A tracking poll is a poll repeated at intervals generally averaged over a trailing window. For example, a weekly tracking poll uses the data from the past week and discards older data.A key benefit of tracking polls is that the trend of a tracking poll (the change over time) corrects for bias: regardless of whether a poll consistently over or underestimates opinion, the trend correctly reflects increases or decreases .
A caution is that estimating the trend is more difficult and error-prone than estimating the level – intuitively, if one estimates the change, the difference between two numbers X and Y, then one has to contend with the error in both X and Y – it is not enough to simply take the difference, as the change may be random noise. For details, see t-test. A rough guide is that if the change in measurement falls outside the margin of error, it is worth attention.
Potential for inaccuracy
Polls based on samples of populations are subject to sampling errorSampling error
-Random sampling:In statistics, sampling error or estimation error is the error caused by observing a sample instead of the whole population. The sampling error can be found by subtracting the value of a parameter from the value of a statistic...
which reflects the effects of chance and uncertainty in the sampling process. The uncertainty is often expressed as a margin of error
Margin of error
The margin of error is a statistic expressing the amount of random sampling error in a survey's results. The larger the margin of error, the less faith one should have that the poll's reported results are close to the "true" figures; that is, the figures for the whole population...
. The margin of error is usually defined as the radius of a confidence interval for a particular statistic from a survey. One example is the percent of people who prefer product A versus product B. When a single, global margin of error is reported for a survey, it refers to the maximum margin of error for all reported percentages using the full sample from the survey. If the statistic is a percentage, this maximum margin of error can be calculated as the radius of the confidence interval for a reported percentage of 50%. Others suggest that a poll with a random sample of 1,000 people has margin of sampling error of 3% for the estimated percentage of the whole population.
A 3% margin of error means that if the same procedure is used a large number of times, 95% of the time the true population average will be within the 95% confidence interval of the sample estimate plus or minus 3%. The margin of error can be reduced by using a larger sample, however if a pollster wishes to reduce the margin of error to 1% they would need a sample of around 10,000 people. In practice, pollsters need to balance the cost of a large sample against the reduction in sampling error and a sample size of around 500–1,000 is a typical compromise for political polls. (Note that to get complete responses it may be necessary to include thousands of additional participators.)
Another way to reduce the margin of error is to rely on poll average
Poll average
A poll average is the result of someone taking the combined information from many different opinion polls that deal with the same issue and synthesizing the information into a new set of numbers....
s. This makes the assumption that the procedure is similar enough between many different polls and uses the sample size of each poll to create a polling average. An example of a polling average can be found here: 2008 Presidential Election polling average. Another source of error stems from faulty demographic models by pollsters who weigh their samples by particular variables such as party identification in an election. For example, if you assume that the breakdown of the US population by party identification has not changed since the previous presidential election, you may underestimate a victory or a defeat of a particular party candidate that saw a surge or decline in its party registration relative to the previous presidential election cycle.
Over time, a number of theories and mechanisms have been offered to explain erroneous polling results. Some of these reflect errors on the part of the pollsters; many of them are statistical in nature. Others blame the respondents for not giving candid answers (e.g., the Bradley effect
Bradley effect
The Bradley effect, less commonly called the Wilder effect, is a theory proposed to explain observed discrepancies between voter opinion polls and election outcomes in some United States government elections where a white candidate and a non-white candidate run against each other...
, the Shy Tory Factor
Shy Tory Factor
Shy Tory Factor is a name given by British opinion polling companies to a phenomenon observed in the 1990s, where the share of the vote won by the Conservative Party in elections was substantially higher than the proportion of people in opinion polls who said they would vote for the party.In the...
); these can be more controversial.
Nonresponse bias
Since some people do not answer calls from strangers, or refuse to answer the poll, poll samples may not be representative samples from a population due to a non-response biasNon-response bias
Non-response bias occurs in statistical surveys if the answers of respondents differ from the potential answers of those who did not answer.- Example :...
. Because of this selection bias
Selection bias
Selection bias is a statistical bias in which there is an error in choosing the individuals or groups to take part in a scientific study. It is sometimes referred to as the selection effect. The term "selection bias" most often refers to the distortion of a statistical analysis, resulting from the...
, the characteristics of those who agree to be interviewed may be markedly different from those who decline. That is, the actual sample is a biased version of the universe the pollster wants to analyze. In these cases, bias introduces new errors, one way or the other, that are in addition to errors caused by sample size. Error due to bias does not become smaller with larger sample sizes, because taking a larger sample size simply repeats the same mistake on a larger scale. If the people who refuse to answer, or are never reached, have the same characteristics as the people who do answer, then the final results should be unbiased. If the people who do not answer have different opinions then there is bias in the results. In terms of election polls, studies suggest that bias effects are small, but each polling firm has its own techniques for adjusting weights to minimize selection bias.
Response bias
Survey results may be affected by response biasResponse bias
Response bias is a type of cognitive bias which can affect the results of a statistical survey if respondents answer questions in the way they think the questioner wants them to answer rather than according to their true beliefs...
, where the answers given by respondents do not reflect their true beliefs. This may be deliberately engineered by unscrupulous pollsters in order to generate a certain result or please their clients, but more often is a result of the detailed wording or ordering of questions (see below). Respondents may deliberately try to manipulate the outcome of a poll by e.g. advocating a more extreme position than they actually hold in order to boost their side of the argument or give rapid and ill-considered answers in order to hasten the end of their questioning. Respondents may also feel under social pressure not to give an unpopular answer. For example, respondents might be unwilling to admit to unpopular attitudes like racism
Racism
Racism is the belief that inherent different traits in human racial groups justify discrimination. In the modern English language, the term "racism" is used predominantly as a pejorative epithet. It is applied especially to the practice or advocacy of racial discrimination of a pernicious nature...
or sexism
Sexism
Sexism, also known as gender discrimination or sex discrimination, is the application of the belief or attitude that there are characteristics implicit to one's gender that indirectly affect one's abilities in unrelated areas...
, and thus polls might not reflect the true incidence of these attitudes in the population. In American political parlance, this phenomenon is often referred to as the Bradley Effect
Bradley effect
The Bradley effect, less commonly called the Wilder effect, is a theory proposed to explain observed discrepancies between voter opinion polls and election outcomes in some United States government elections where a white candidate and a non-white candidate run against each other...
. If the results of surveys are widely publicized this effect may be magnified - a phenomenon commonly referred to as the spiral of silence
Spiral of silence
The spiral of silence is a political science and mass communication theory propounded by the German political scientist Elisabeth Noelle-Neumann...
.
Wording of questions
It is well established that the wording of the questions, the order in which they are asked and the number and form of alternative answers offered can influence results of polls. For instance, the public is more likely to indicate support for a person who is described by the operator as one of the "leading candidates". This support itself overrides subtle bias for one candidate, as does lumping some candidates in an "other" category or vice versa. Thus comparisons between polls often boil down to the wording of the question. On some issues, question wording can result in quite pronounced differences between surveys. This can also, however, be a result of legitimately conflicted feelings or evolving attitudes, rather than a poorly constructed survey.A common technique to control for this bias is to rotate the order in which questions are asked. Many pollsters also split-sample. This involves having two different versions of a question, with each version presented to half the respondents.
The most effective controls, used by attitude
Attitude (psychology)
An attitude is a hypothetical construct that represents an individual's degree of like or dislike for something. Attitudes are generally positive or negative views of a person, place, thing, or event— this is often referred to as the attitude object...
researchers, are:
- asking enough questions to allow all aspects of an issue to be covered and to control effects due to the form of the question (such as positive or negative wording), the adequacy of the number being established quantitatively with psychometricPsychometricsPsychometrics is the field of study concerned with the theory and technique of psychological measurement, which includes the measurement of knowledge, abilities, attitudes, personality traits, and educational measurement...
measures such as reliability coefficients, and - analyzing the results with psychometric techniques which synthesize the answers into a few reliable scores and detect ineffective questions.
These controls are not widely used in the polling industry .
Coverage bias
Another source of error is the use of samples that are not representative of the population as a consequence of the methodology used, as was the experience of the Literary Digest in 1936. For example, telephone sampling has a built-in error because in many times and places, those with telephones have generally been richer than those without.In some places many people have only mobile telephones. Because pollsters cannot call mobile phones (it is unlawful in the United States to make unsolicited calls to phones where the phone's owner may be charged simply for taking a call), these individuals will never be included in the polling sample. If the subset of the population without cell phones differs markedly from the rest of the population, these differences can skew the results of the poll. Polling organizations have developed many weighting techniques to help overcome these deficiencies, to varying degrees of success. Studies of mobile phone users by the Pew Research Center in the US concluded that "cell-only respondents are different from landline respondents in important ways, (but) they were neither numerous enough nor different enough on the questions we examined to produce a significant change in overall general population survey estimates when included with the landline samples and weighted according to US Census parameters on basic demographic characteristics."
This issue was first identified in 2004, but came to prominence only during the 2008 US presidential election
United States presidential election, 2008
The United States presidential election of 2008 was the 56th quadrennial presidential election. It was held on November 4, 2008. Democrat Barack Obama, then the junior United States Senator from Illinois, defeated Republican John McCain, the senior U.S. Senator from Arizona. Obama received 365...
. In previous elections, the proportion of the general population using cell phones was small, but as this proportion has increased, the worry is that polling only landlines is no longer representative of the general population. In 2003, a 2.9% of households were wireless (cellphones only) compared to 12.8 in 2006. This results in "coverage error". Many polling organisations select their sample by dialling random telephone numbers; however, there is a clear tendency for polls which included mobile phones in their sample to show a much larger lead for Obama
Barack Obama
Barack Hussein Obama II is the 44th and current President of the United States. He is the first African American to hold the office. Obama previously served as a United States Senator from Illinois, from January 2005 until he resigned following his victory in the 2008 presidential election.Born in...
than polls that did not.
The potential sources of bias are:
- Some households use cellphones only and have no landline. This tends to include minorities and younger voters; and occurs more frequently in metropolitan areas. Men are more likely to be cellphone-only compared to women.
- Some people may not be contactable by landline from Monday to Friday and may be contactable only by cellphone.
- Some people use their landlines only to access the Internet, and answer calls only to their cellphones.
Some polling companies have attempted to get around that problem by including a "cellphone supplement". There are a number of problems with including cellphones in a telephone poll:
- It is difficult to get co-operation from cellphone users, because in many parts of the US, users are charged for both outgoing and incoming calls. That means that pollsters have had to offer financial compensation to gain co-operation.
- US federal law prohibits the use of automated dialling devices to call cellphones (Telephone Consumer Protection Act of 1991Telephone Consumer Protection Act of 1991The Telephone Consumer Protection Act of 1991 was passed by the United States Congress in 1991 and signed into law by President George H. W. Bush as Public Law 102-243, amending the Communications Act of 1934. The current version of the statute is found principally at...
). Numbers therefore have to be dialled by hand, which is more time-consuming and expensive for pollsters.
An oft-quoted example of opinion polls succumbing to errors was the UK General Election of 1992. Despite the polling organizations using different methodologies virtually all the polls in the lead up to the vote, and to a lesser extent exit poll
Exit poll
An election exit poll is a poll of voters taken immediately after they have exited the polling stations. Unlike an opinion poll, which asks whom the voter plans to vote for or some similar formulation, an exit poll asks whom the voter actually voted for. A similar poll conducted before actual...
s taken on voting day, showed a lead for the opposition Labour party but the actual vote gave a clear victory to the ruling Conservative party.
In their deliberations after this embarrassment the pollsters advanced several ideas to account for their errors, including:
Late swing
Swing (politics)
An electoral swing analysis shows the extent of change in voter support from one election to another. It is an indicator of voter support for individual candidates or political parties, or voter preference between two or more candidates or parties...
: Voters who changed their minds shortly before voting tended to favour the Conservatives, so the error was not as great as it first appeared.
Nonresponse bias : Conservative voters were less likely to participate in surveys than in the past and were thus under-represented.
The Shy Tory Factor
Shy Tory Factor
Shy Tory Factor is a name given by British opinion polling companies to a phenomenon observed in the 1990s, where the share of the vote won by the Conservative Party in elections was substantially higher than the proportion of people in opinion polls who said they would vote for the party.In the...
: The Conservatives had suffered a sustained period of unpopularity as a result of economic difficulties and a series of minor scandals, leading to a spiral of silence
Spiral of silence
The spiral of silence is a political science and mass communication theory propounded by the German political scientist Elisabeth Noelle-Neumann...
in which some Conservative supporters were reluctant to disclose their sincere intentions to pollsters.
The relative importance of these factors was, and remains, a matter of controversy, but since then the polling organizations have adjusted their methodologies and have achieved more accurate results in subsequent elections.
Polling organizations
In AustraliaAustralia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
the most notable companies are:
- NewspollNewspollNewspoll Market Research is an Australian company providing opinion polling and other market research services. Its chief executive is Martin O'Shannessy.Newspoll's surveys of voter opinion are published in The Australian....
- published in News Limited'sNews LimitedNews Limited is one of Australia's largest diversified media companies. The publicly listed company's interests span newspaper and magazine publishing, Internet, Pay TV, National Rugby League, market research, DVD and film distribution, and film and television production trading assets.News Limited...
The AustralianThe AustralianThe Australian is a broadsheet newspaper published in Australia from Monday to Saturday each week since 14 July 1964. The editor in chief is Chris Mitchell, the editor is Clive Mathieson and the 'editor-at-large' is Paul Kelly....
newspaper - Roy Morgan ResearchRoy Morgan ResearchRoy Morgan Research is an Australian market research company headquartered in Melbourne, Victoria; it was founded in 1941 by Roy Morgan ; its Executive Chairman today is his son, Gary Morgan....
- published in the CrikeyCrikeyCrikey is an independent Australian electronic magazine comprising an open access website and an email newsletter available to subscribers. Well known in Australian political, media and business circles, Crikey was described by former Federal Opposition Leader Mark Latham as the "most popular...
email reporting service - Galaxy PollingGalaxy ResearchGalaxy Research is an Australian market researching company which has expanded into providing opinion polling for State and Federal politics. It is principally managed by David Briggs...
- published in News Limited'sNews LimitedNews Limited is one of Australia's largest diversified media companies. The publicly listed company's interests span newspaper and magazine publishing, Internet, Pay TV, National Rugby League, market research, DVD and film distribution, and film and television production trading assets.News Limited...
tabloid papers - AC Nielsen PollingACNielsenACNielsen is a global marketing research firm, with worldwide headquarters in New York City. Regional headquarters for North America are located in Schaumburg, Illinois. As of May 2010, it is part of The Nielsen Company.-History:...
- published in FairfaxFairfax MediaFairfax Media Limited is one of Australia's largest diversified media companies. The group's operations include newspapers, magazines, radios and digital media operating in Australia and New Zealand. Fairfax Media was founded by the Fairfax family as John Fairfax and Sons, later to become John...
newspapers - Ipsos and I-View
In Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
the most notable companies are:
- IBOPEIBOPEIBOPE was established in Brazil in 1942 and provides the largest collection of information in Brazilian and Latin American markets...
(Instituto Brasileiro de Opinião Pública) which acronym has become the Brazilian household word for TV audience rating and a slang word that indicates that a meeting or similar function had significant attendance. - Datafolha
In Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
the most notable companies are:
- Angus Reid StrategiesAngus Reid StrategiesAngus Reid Public Opinion is an international public affairs practice. It was established in 2006 under the name Angus Reid Strategies by Dr Angus Reid, a Canadian sociologist who founded his first research company in 1979. Reid sold the Angus Reid Group to Paris-based Ipsos SA in 2000...
- EKOS Research AssociatesEKOS Research AssociatesEKOS Research Associates Inc. is a Canadian social and economic research company founded by Carleton University graduate Frank Graves. They specialize in market research, public opinion research, strategic communications advice, program evaluation and performance measurement, and human resources...
- Environics Research Group
- Harris/Decima
- Ipsos-ReidIpsos-ReidIpsos Reid is a research company based in Canada and is the Canadian arm of the global Ipsos Group. Founded in Winnipeg in 1979, the company expanded across the country and became part of the Ipsos Group in 2000....
- Léger MarketingLéger MarketingLeger Marketing is the largest solely Canadian owned polling and market research firm in Canada with 650 employees, including 103 professionals. Leger Marketing provides access to Canadian and American markets...
- Nanos Research
In Egypt
Egypt
Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...
, the most notable polling organization is
- Opinion Poll Center
In Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
, notable polling organizations are
- Allensbach InstituteAllensbach InstituteThe Allensbach Institute, formally the Allensbach Institute for Public Opinion Research or Allensbach Institute for Public Opinion Polling , is a private conservativeopinion polling institute based in Allensbach, Baden-Württemberg, Germany....
- Forsa instituteForsa instituteThe forsa Institute for Social Research and Statistical Analysis , forsa for short, is one of the leading market research and opinion polling companies in Germany...
- Infratest dimap
- TNS Emnid
In Jordan
Jordan
Jordan , officially the Hashemite Kingdom of Jordan , Al-Mamlaka al-Urduniyya al-Hashemiyya) is a kingdom on the East Bank of the River Jordan. The country borders Saudi Arabia to the east and south-east, Iraq to the north-east, Syria to the north and the West Bank and Israel to the west, sharing...
the dominant organization is:
- Knowledge World Center for Polls
In Iran
Iran
Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...
, some notable polling organisations include:
- AyandehAyandeh (polling organisation)Ayandeh is an opinion poll organisation in Iran that was closed down in 2002.One of Ayandeh's directors, Abbas Abdi, was arrested in at his home on 4 November 2002, accused of "having received money from either the US polling firm Gallup or a foreign embassy". Abdi spent several years in prison...
- closed in 2002 and director Abbas AbdiAbbas AbdiAbbas Abdi is one of Iran's most influential reformists, journalist, self-taught sociologist and social activist.Abdi studied Polymer engineering at Poly Technique University in Tehran. He was a member of editorial board of Salam newspaper...
arrested
In New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
, some notable polling organisations include:
- Colmar BruntonColmar BruntonColmar Brunton is an international market research agency. It is also Australia's largest independent market research agency.Its head office is in Sydney, Australia, with other offices in the Australian cities of Melbourne, Brisbane, Adelaide and Canberra, as well as in New Zealand and...
- UMR Insight
In Nigeria
Nigeria
Nigeria , officially the Federal Republic of Nigeria, is a federal constitutional republic comprising 36 states and its Federal Capital Territory, Abuja. The country is located in West Africa and shares land borders with the Republic of Benin in the west, Chad and Cameroon in the east, and Niger in...
the most notable polling organisation is:
- NOI-Gallup pollNOI pollThe NOI poll is an opinion poll conducted by NOI Global Consulting, a non governmental organization established by former Finance Minister of Nigeria Ngozi Okonjo-Iweala, in collaboration with the Gallup Organization, to be used as a representation of Nigerian public opinion...
In South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
, some notable polling organisations include:
- Ipsos Markinor who have conducted opinion polls since 1976.
- Plus 94 Research - published in Sunday Times South Africa newspaper
In Ukraine
Ukraine
Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...
, the most notable pollsters are:
- Research & Branding GroupResearch & Branding GroupResearch & Branding Group is a Ukrainian non-governmental marketing and sociological research company.Worked with Party of Regions during several latest elections....
, widely published throughout Ukraine and Internationally. Works include exit polls and regular surveys of the public's political opinions - Razumkov CentreRazumkov CentreRazumkov Centre , or fully the Ukrainian Centre for Economic and Political Studies named after Olexander Razumkov , is a Ukrainian non-governmental public policy think tank....
A policy think tank also widely published throughout Ukraine - SOCIS (Socis center for social and political studies)
In the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, the most notable pollsters are:
- ComResComResComRes is a polling and research consultancy with British origins. The company has its registered company headquarters in London, United Kingdom and also has offices in Brussels, Edinburgh and Cardiff...
, retained pollster for the BBCBBCThe British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...
and The IndependentThe IndependentThe Independent is a British national morning newspaper published in London by Independent Print Limited, owned by Alexander Lebedev since 2010. It is nicknamed the Indy, while the Sunday edition, The Independent on Sunday, is the Sindy. Launched in 1986, it is one of the youngest UK national daily... - Ipsos MORI (formerly MORI).
- YouGovYouGovYouGov, formerly known as PollingPoint in the United States, is an international internet-based market research firm launched in the UK in May 2000 by Stephan Shakespeare, now Chief Executive Officer, and Nadhim Zahawi...
. - GfK NOPGfK NOPGfK NOP is a leading market research agency based in London, providing business insight through quantitative and qualitative research.- History :...
- ICMICM (polling)ICM Research is a public opinion researcher registered in England . It is a subsidiary of Creston plc, a marketing services company.-Business:...
- PopulusPopulus LtdPopulus is a market research company in the United Kingdom formed in 2003. Populus co-founded the British Polling Council in 2004 and regularly publishes opinion polls on voting intention and as well as other political and commercial issues. Clients have included national brands such as the AA and...
, official The TimesThe TimesThe Times is a British daily national newspaper, first published in London in 1785 under the title The Daily Universal Register . The Times and its sister paper The Sunday Times are published by Times Newspapers Limited, a subsidiary since 1981 of News International...
pollster
In the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, some notable companies include:
- Gallup poll run by The Gallup OrganizationThe Gallup OrganizationThe Gallup Organization, is primarily a research-based performance-management consulting company. Some of Gallup's key practice areas are - Employee Engagement, Customer Engagement and Well-Being. Gallup has over 40 offices in 27 countries. World headquarters are in Washington, D.C. Operational...
- Harris Poll
- IpsosIpsosIpsos S.A. is a global market research company headquartered in Paris, France. The Company was founded in 1975 and has been publicly traded on the Paris Stock Exchange since 1 July 1999...
- National Opinion Research CenterNational Opinion Research CenterNORC at the University of Chicago, established in 1941 as the National Opinion Research Center, is one of the largest and most highly respected social research organizations in the United States. Its corporate headquarters are located on the University of Chicago campus...
- Nielsen ratingsNielsen RatingsNielsen ratings are the audience measurement systems developed by Nielsen Media Research, in an effort to determine the audience size and composition of television programming in the United States...
- Pew Research CenterPew Research CenterThe Pew Research Center is an American think tank organization based in Washington, D.C. that provides information on issues, attitudes and trends shaping the United States and the world. The Center and its projects receive funding from The Pew Charitable Trusts. In 1990, Donald S...
- Rasmussen ReportsRasmussen ReportsRasmussen Reports is an American media company that publishes and distributes information based on public opinion polling. Founded by pollster Scott Rasmussen in 2003, the company updates daily indexes including the President's job approval rating, and provides public opinion data, analysis, and...
- Research 2000Research 2000Research 2000 is a U.S. opinion polling and marketing research company based in Olney, Maryland. It began doing research on upcoming elections in 1999 after its President, Del Ali, moved on from Mason-Dixon Political Media Research...
- YouGovYouGovYouGov, formerly known as PollingPoint in the United States, is an international internet-based market research firm launched in the UK in May 2000 by Stephan Shakespeare, now Chief Executive Officer, and Nadhim Zahawi...
. - Zogby InternationalZogby InternationalIBOPE Zogby International is an international market research, opinion polling firm founded in 1984 by John Zogby. The company polls and consults for a wide spectrum of business media, government, and political groups, and conducts public opinion research in more than 70 countries...
In Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
:
- Metroscopia
- Sigma 2
- TNS Demoscopia
- OpinaOpináOpiná is a village and municipality in Košice-okolie District in the Kosice Region of eastern Slovakia.-Geography:The village lies at an altitude of 367 metres and covers an area of 11.953 km².It has a population of about 180 people.-External links:*...
- Akra Delta
- Netquest
- ESEQ, Estudios sociales, políticos y de mercado
- IpsosIpsosIpsos S.A. is a global market research company headquartered in Paris, France. The Company was founded in 1975 and has been publicly traded on the Paris Stock Exchange since 1 July 1999...
All the major television network
Television network
A television network is a telecommunications network for distribution of television program content, whereby a central operation provides programming to many television stations or pay TV providers. Until the mid-1980s, television programming in most countries of the world was dominated by a small...
s, alone or in conjunction with the largest newspapers or magazines, in virtually every country with elections, operate their own versions of polling operations, in collaboration or independently through various applications. One of the applications can be found on Facebook
Several organizations try to monitor the behavior of polling firms and the use of polling and statistical data, including the Pew Research Center
Pew Research Center
The Pew Research Center is an American think tank organization based in Washington, D.C. that provides information on issues, attitudes and trends shaping the United States and the world. The Center and its projects receive funding from The Pew Charitable Trusts. In 1990, Donald S...
and, in Canada, the Laurier Institute for the Study of Public Opinion and Policy.
Failures
The best-known failure of opinion polling to date in the United StatesUnited States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
was the prediction that Thomas Dewey
Thomas Dewey
Thomas Edmund Dewey was the 47th Governor of New York . In 1944 and 1948, he was the Republican candidate for President, but lost both times. He led the liberal faction of the Republican Party, in which he fought conservative Ohio Senator Robert A. Taft...
would defeat Harry S. Truman
Harry S. Truman
Harry S. Truman was the 33rd President of the United States . As President Franklin D. Roosevelt's third vice president and the 34th Vice President of the United States , he succeeded to the presidency on April 12, 1945, when President Roosevelt died less than three months after beginning his...
in the 1948 US presidential election. Major polling organizations, including Gallup and Roper, indicated a landslide victory for Dewey.
In the United Kingdom, most polls failed to predict the Conservative election victories of 1970
United Kingdom general election, 1970
The United Kingdom general election of 1970 was held on 18 June 1970, and resulted in a surprise victory for the Conservative Party under leader Edward Heath, who defeated the Labour Party under Harold Wilson. The election also saw the Liberal Party and its new leader Jeremy Thorpe lose half their...
and 1992
United Kingdom general election, 1992
The United Kingdom general election of 1992 was held on 9 April 1992, and was the fourth consecutive victory for the Conservative Party. This election result was one of the biggest surprises in 20th Century politics, as polling leading up to the day of the election showed Labour under leader Neil...
, and Labour's victory in 1974
United Kingdom general election, 1974
There were two general elections held in the United Kingdom in 1974:*United Kingdom general election, February 1974*United Kingdom general election, October 1974...
. However, their figures at other elections have been generally accurate.
Effect on voters
By providing information about voting intentions, opinion polls can sometimes influence the behavior of electors, and in his book The Broken CompassThe Broken Compass: How British Politics Lost its Way
The Broken Compass: How British Politics Lost its Way is the fourth book from English traditionalist conservative writer Peter Hitchens...
, Peter Hitchens
Peter Hitchens
Peter Jonathan Hitchens is an award-winning British columnist and author, noted for his traditionalist conservative stance. He has published five books, including The Abolition of Britain, A Brief History of Crime, The Broken Compass and most recently The Rage Against God. Hitchens writes for...
asserts that opinion polls are actually a device for influencing public opinion. The various theories about how this happens can be split into two groups: bandwagon/underdog effects, and strategic ("tactical") voting.
A bandwagon effect
Bandwagon effect
The bandwagon effect is a well documented form of groupthink in behavioral science and has many applications. The general rule is that conduct or beliefs spread among people, as fads and trends clearly do, with "the probability of any individual adopting it increasing with the proportion who have...
occurs when the poll prompts voters to back the candidate shown to be winning in the poll. The idea that voters are susceptible to such effects is old, stemming at least from 1884; William Safire
William Safire
William Lewis Safire was an American author, columnist, journalist and presidential speechwriter....
reported that the term was first used in a political cartoon in the magazine Puck
Puck (magazine)
Puck was America's first successful humor magazine of colorful cartoons, caricatures and political satire of the issues of the day. It was published from 1871 until 1918.-History:...
in that year. It has also remained persistent in spite of a lack of empirical corroboration until the late 20th century. George Gallup
George Gallup
George Horace Gallup was an American pioneer of survey sampling techniques and inventor of the Gallup poll, a successful statistical method of survey sampling for measuring public opinion.-Biography:...
spent much effort in vain trying to discredit this theory in his time by presenting empirical research. A recent meta-study of scientific research on this topic indicates that from the 1980s onward the Bandwagon effect is found more often by researchers.
The opposite of the bandwagon effect is the underdog
Underdog (competition)
An underdog is a person or group in a competition, frequently in electoral politics, sports and creative works, who is popularly expected to lose. The party, team or individual expected to win is called the favorite or top dog. In the rare case where an underdog wins, the outcome is an upset. These...
effect. It is often mentioned in the media. This occurs when people vote, out of sympathy, for the party perceived to be "losing" the elections. There is less empirical evidence for the existence of this effect than there is for the existence of the bandwagon effect.
The second category of theories on how polls directly affect voting is called strategic or tactical voting
Tactical voting
In voting systems, tactical voting occurs, in elections with more than two viable candidates, when a voter supports a candidate other than his or her sincere preference in order to prevent an undesirable outcome.It has been shown by the Gibbard-Satterthwaite theorem that any voting method which is...
. This theory is based on the idea that voters view the act of voting as a means of selecting a government. Thus they will sometimes not choose the candidate they prefer on ground of ideology or sympathy, but another, less-preferred, candidate from strategic considerations. An example can be found in the United Kingdom general election, 1997
United Kingdom general election, 1997
The United Kingdom general election, 1997 was held on 1 May 1997, more than five years after the previous election on 9 April 1992, to elect 659 members to the British House of Commons. The Labour Party ended its 18 years in opposition under the leadership of Tony Blair, and won the general...
. As he was then a Cabinet Minister, Michael Portillo
Michael Portillo
Michael Denzil Xavier Portillo is a British journalist, broadcaster, and former Conservative Party politician and Cabinet Minister...
's constituency of Enfield Southgate was believed to be a safe seat
Safe seat
A safe seat is a seat in a legislative body which is regarded as fully secured, either by a certain political party, the incumbent representative personally or a combination of both...
but opinion polls showed the Labour
Labour Party (UK)
The Labour Party is a centre-left democratic socialist party in the United Kingdom. It surpassed the Liberal Party in general elections during the early 1920s, forming minority governments under Ramsay MacDonald in 1924 and 1929-1931. The party was in a wartime coalition from 1940 to 1945, after...
candidate Stephen Twigg
Stephen Twigg
Stephen Twigg is a British Labour Party politician who has been the Labour Co-operative Member of Parliament for Liverpool West Derby since 2010. He previously served as the Member of Parliament for Enfield Southgate from 1997 to 2005, when he lost his seat. He came to national prominence in 1997...
steadily gaining support, which may have prompted undecided voters or supporters of other parties to support Twigg in order to remove Portillo. Another example is the boomerang effect where the likely supporters of the candidate shown to be winning feel that chances are slim and that their vote is not required, thus allowing another candidate to win.
In addition, Mark Pickup in Cameron Anderson and Laura Stephenson's "Voting Behaviour in Canada" outlines three additional "behavioural" responses that voters may exhibit when faced with polling data.
The first is known as a "cue taking" effect which holds that poll data is used as a "proxy" for information about the candidates or parties. Cue taking is "based on the psychological phenomenon of using heuristics to simplify a complex decision" (243)
The second, first described by Petty and Cacioppo (1996) is known as "cognitive response" theory. This theory asserts that a voter's response to a poll may not line with their initial conception of the electoral reality. In response, the voter is likely to generate a "mental list" in which they create reasons for a party's loss or gain in the polls. This can reinforce or change their opinion of the candidate and thus affect voting behaviour.
Third, the final possibility is a "behavioural response" which is similar to a cognitive response. The only salient difference is that a voter will go and seek new information to form their "mental list," thus becoming more informed of the election. This may then affect voting behaviour.
These effects indicate how opinion polls can directly affect political choices of the electorate. But directly or indirectly, other effects can be surveyed and analyzed on all political parties. The form of media framing
Framing (social sciences)
A frame in social theory consists of a schema of interpretation — that is, a collection of anecdotes and stereotypes—that individuals rely on to understand and respond to events. In simpler terms, people build a series of mental filters through biological and cultural influences. They use these...
and party ideology shifts must also be taken under consideration. Opinion polling in some instances is a measure of cognitive bias, which is variably considered and handled appropriately in its various applications.
Effect on politicians
Starting in the 1980s, tracking polls and related technologies began having a notable impact on U.S. political leaders. According to Douglas Bailey, a Republican who had helped run Gerald FordGerald Ford
Gerald Rudolph "Jerry" Ford, Jr. was the 38th President of the United States, serving from 1974 to 1977, and the 40th Vice President of the United States serving from 1973 to 1974...
's 1976 presidential campaign
United States presidential election, 1976
The United States presidential election of 1976 followed the resignation of President Richard Nixon in the wake of the Watergate scandal. It pitted incumbent President Gerald Ford, the Republican candidate, against the relatively unknown former governor of Georgia, Jimmy Carter, the Democratic...
, "It's no longer necessary for a political candidate to guess what an audience thinks. He can [find out] with a nightly tracking poll. So it's no longer likely that political leaders are going to lead. Instead, they're going to follow."
Regulation
Some jurisdictions over the world restrict the publication of the results of opinion polls in order to prevent the possibly erroneous results from affecting voters' decisions. For instance, in Canada, it is prohibited to publish the results of opinion surveys that would identify specific political parties or candidates in the final three days before a poll closes.However, most western democratic nations don't support the entire prohibition of the publication of pre-election opinion polls; most of them have no regulation and some only prohibit it in the final days or hours until the relevant poll closes. A survey by Canada's Royal Commission on Electoral Reform reported that the prohibition period of publication of the survey results largely differed in different countries. Out of the 20 countries examined, three prohibit the publication during the entire period of campaigns, while others prohibit it for a shorter term such as the polling period or the final 48 hours before a poll closes.
See also
- Deliberative opinion pollDeliberative opinion pollThe deliberative opinion poll is a form of opinion poll that incorporates the principles of deliberative democracy and sortition.The concept was described by James S. Fishkin in his 1991 book "Democracy and Deliberation". Dr...
- Entrance pollEntrance pollAn entrance poll is a poll that is taken before voters have cast their votes at the polling stations. It is akin to an opinion poll in the sense that it asks who the voter plans to vote for or some similar set of questions...
- Exit pollExit pollAn election exit poll is a poll of voters taken immediately after they have exited the polling stations. Unlike an opinion poll, which asks whom the voter plans to vote for or some similar formulation, an exit poll asks whom the voter actually voted for. A similar poll conducted before actual...
- Open access poll
- Push pollPush pollA push poll is a political campaign technique in which an individual or organization attempts to influence or alter the view of respondents under the guise of conducting a poll. In a push poll, large numbers of respondents are contacted, and little or no effort is made to collect and analyze...
- Straw pollStraw pollA straw poll or straw vote is a vote with nonbinding results. Straw polls provide dialogue among movements within large groups, reflecting trends like organization and motivation...
- Sample size determination
- Electoral CalculusElectoral CalculusElectoral Calculus is a psephological web site which attempts to predict future United Kingdom general election results. It was developed by Martin Baxter and employs scientific techniques on data about Britain's electoral geography....
United Kingdom election prediction website
External references
- Asher, Herbert: Polling and the Public. What Every Citizen Should Know, fourth edition. Washington, D.C.: CQ Press, 1998.
- Bourdieu, PierrePierre BourdieuPierre Bourdieu was a French sociologist, anthropologist, and philosopher.Starting from the role of economic capital for social positioning, Bourdieu pioneered investigative frameworks and terminologies such as cultural, social, and symbolic capital, and the concepts of habitus, field or location,...
, "Public Opinion does not exist" in Sociology in Question, London, Sage (1995). - Bradburn, Norman M. and Seymour Sudman. Polls and Surveys: Understanding What They Tell Us (1988).
- Cantril, Hadley. Gauging Public Opinion (1944).
- Cantril, Hadley and Mildred Strunk, eds. Public Opinion, 1935-1946 (1951), massive compilation of many public opinion polls from US, UK, Canada, Australia, and elsewhere.
- Converse, Jean M. Survey Research in the United States: Roots and Emergence 1890-1960 (1987), the standard history.
- Crespi, Irving. Public Opinion, Polls, and Democracy (1989).
- Gallup, George. Public Opinion in a Democracy (1939).
- Gallup, Alec M. ed. The Gallup Poll Cumulative Index: Public Opinion, 1935-1997 (1999) lists 10,000+ questions, but no results.
- Gallup, George Horace, ed. The Gallup Poll; Public Opinion, 1935-1971 3 vol (1972) summarizes results of each poll.
- Glynn, Carroll J., Susan Herbst, Garrett J. O'Keefe, and Robert Y. Shapiro. Public Opinion (1999) textbook
- Lavrakas, Paul J. et al. eds. Presidential Polls and the News Media (1995)
- Moore, David W. The Superpollsters: How They Measure and Manipulate Public Opinion in America (1995).
- Niemi, Richard G., John Mueller, Tom W. Smith, eds. Trends in Public Opinion: A Compendium of Survey Data (1989).
- Oskamp, Stuart and P. Wesley Schultz; Attitudes and Opinions (2004).
- Robinson, Claude E. Straw Votes (1932).
- Robinson, Matthew Mobocracy: How the Media's Obsession with Polling Twists the News, Alters Elections, and Undermines Democracy (2002).
- Rogers, Lindsay. The Pollsters: Public Opinion, Politics, and Democratic Leadership (1949).
- Traugott, Michael W. The Voter's Guide to Election Polls 3rd ed. (2004).
- James G. Webster, Patricia F. Phalen, Lawrence W. Lichty; Ratings Analysis: The Theory and Practice of Audience Research Lawrence Erlbaum Associates, 2000.
- Young, Michael L. Dictionary of Polling: The Language of Contemporary Opinion Research (1992).
Additional Sources
- Walden, Graham R. Survey Research Methodology, 1990-1999: An Annotated Bibliography. Bibliographies and Indexes in Law and Political Science Series. Westport, CT: Greenwood Press, Greenwood Publishing Group, Inc., 2002. xx, 432p.
- Walden, Graham R. Public Opinion Polls and Survey Research: A Selective Annotated Bibliography of U.S. Guides and Studies from the 1980s. Public Affairs and Administrative Series, edited by James S. Bowman, vol. 24. New York, NY: Garland Publishing Inc., 1990. xxix, 360p.
- Walden, Graham R. Polling and Survey Research Methods 1935-1979: An Annotated Bibliography. Bibliographies and Indexes in Law and Political Science Series, vol. 25. Westport, CT: Greenwood Publishing Group, Inc., 1996. xxx, 581p.
External links
- Polls from UCB Libraries GovPubs
- The Pew Research Center nonpartisan "fact tank" providing information on the issues, attitudes and trends shaping America and the world by conducting public opinion polling and social science research
- "Use Opinion Research To Build Strong Communication" by Frank Noto
- Public Agenda for Citizens nonpartisan, nonprofit group that tracks public opinion data in the United States
- National Council on Public Polls association of polling organizations in the United States devoted to setting high professional standards for surveys
- USA Election Polls tracks the public opinion polls related to elections in the US
- Survey Analysis Tool based on A. Berkopec, HyperQuick algorithm for discrete hypergeometric distribution, Journal of Discrete Algorithms, Elsevier, 2006.
- "Poll Position - Issue 010 - GOOD", track record of pollsters for USA presidential elections in Good magazine, April 23, 2008.