Panel data
Encyclopedia
In statistics
and econometrics
, the term panel data refers to multi-dimensional data
. Panel data contains observations on multiple phenomena observed over multiple time periods for the same firms or individuals.
Time series
and cross-sectional
data are special cases of panel data that are in one-dimension only.
In the example above, two data sets with a two-dimensional panel structure are shown. Individual characteristics (income, age, sex. educ) are collected for different persons and different years. In the left data set two persons (1, 2) are observed over three years (2003, 2004, 2005). Because each person is observed every year, the left-hand data set is called a balanced panel, whereas the data set on the right hand is called an unbalanced panel, since Person 1 is not observed in year 2005 and Person 3 is not observed in 2003 or 2005.
where
is the individual dimension and 
is the time dimension. A general panel data regression model is written as 
Different assumptions can be made on the precise structure of this general model. Two important models are the fixed effects model and the random effects model. The fixed effects model is denoted as
are individual-specific, time-invariant effects (for example in a panel of countries this could include geography, climate etc.) and because we assume they are fixed over time, this is called the fixed-effects model. The random effects model assumes in addition that
and
that is, the two error components are independent from each other.
Statistics
Statistics is the study of the collection, organization, analysis, and interpretation of data. It deals with all aspects of this, including the planning of data collection in terms of the design of surveys and experiments....
and econometrics
Econometrics
Econometrics has been defined as "the application of mathematics and statistical methods to economic data" and described as the branch of economics "that aims to give empirical content to economic relations." More precisely, it is "the quantitative analysis of actual economic phenomena based on...
, the term panel data refers to multi-dimensional data
Data set
A data set is a collection of data, usually presented in tabular form. Each column represents a particular variable. Each row corresponds to a given member of the data set in question. Its values for each of the variables, such as height and weight of an object or values of random numbers. Each...
. Panel data contains observations on multiple phenomena observed over multiple time periods for the same firms or individuals.
Time series
Time series
In statistics, signal processing, econometrics and mathematical finance, a time series is a sequence of data points, measured typically at successive times spaced at uniform time intervals. Examples of time series are the daily closing value of the Dow Jones index or the annual flow volume of the...
and cross-sectional
Cross-sectional data
Cross-sectional data or cross section in statistics and econometrics is a type of one-dimensional data set. Cross-sectional data refers to data collected by observing many subjects at the same point of time, or without regard to differences in time...
data are special cases of panel data that are in one-dimension only.
Example
| balanced panel: | unbalanced panel: | |
|---|---|---|
 |
 |
In the example above, two data sets with a two-dimensional panel structure are shown. Individual characteristics (income, age, sex. educ) are collected for different persons and different years. In the left data set two persons (1, 2) are observed over three years (2003, 2004, 2005). Because each person is observed every year, the left-hand data set is called a balanced panel, whereas the data set on the right hand is called an unbalanced panel, since Person 1 is not observed in year 2005 and Person 3 is not observed in 2003 or 2005.
Analysis of panel data
A panel has the formwhere
is the individual dimension and is the time dimension. A general panel data regression model is written as Different assumptions can be made on the precise structure of this general model. Two important models are the fixed effects model and the random effects model. The fixed effects model is denoted as
are individual-specific, time-invariant effects (for example in a panel of countries this could include geography, climate etc.) and because we assume they are fixed over time, this is called the fixed-effects model. The random effects model assumes in addition that
and
that is, the two error components are independent from each other.
Data sets which have a panel design
- German Socio-Economic Panel (SOEP)
- Household, Income and Labour Dynamics in Australia SurveyHousehold, Income and Labour Dynamics in Australia SurveyThe Household, Income and Labour Dynamics in Australia survey is an Australian household-based panel study which began in 2001. It has been used for examining issues such as the incidence of persistent poverty; assets and income in the transition to retirement; the correlates and impact of...
(HILDA) - British Household Panel SurveyBritish Household Panel SurveyThe British Household Panel Survey , carried out at the Institute for Social and Economic Research of the University of Essex, is an instrument for social and economic research. A sample of British households was drawn and first interviewed in 1991. The members of these original households have...
(BHPS) - Survey of Family Income and Employment (SoFIE)
- Survey of Income and Program ParticipationSurvey of Income and Program ParticipationThe Survey of Income and Program Participation is a statistical survey conducted by the United States Census Bureau. The main objective of the SIPP is to provide accurate and comprehensive information about the income of American individuals and households and the participation of these people in...
(SIPP) - Lifelong Labour Market DatabaseLLMDBThe Lifelong Labour Market Database is a panel data set, owned by the Department for Work and Pensions in Britain. LLMDB2 holds a 1% sample from the new National Insurance Recording System and is a fully representative sample of around 600000 people. LLMDB2 started to record the income and other...
(LLMDB) - Panel Study of Income DynamicsPanel Study of Income DynamicsThe Panel Study of Income Dynamics is the world’s longest running household panel survey. The PSID is a longitudinal panel survey of United States families that measures economic, social, and health factors over the life course and across generations...
(PSID) - Korean Labor and Income Panel Study (KLIPS)
- Chinese Family Panel StudiesChinese Family Panel StudiesChinese Family Panel Studies is designed by representative experts from all social sciences departments, schools, and institutes in Peking University, PKU. It’s funded by the national 985 program and started in the early of 2007....
(CFPS) - German Family Panel (pairfam)
- National Longitudinal SurveysNational Longitudinal SurveysThe National Longitudinal Surveys are a set of surveys conducted by the US Department of Labor's Bureau of Labor Statistics, designed to gather information at multiple points in time on significant life events of several population samples of US citizens, especially their labor market...
(NLSY)