MK II FPA
Encyclopedia
The MK II Method is one of the software sizing methods in functional point group of measurements. This is a method for analysis and measurement of information processing applications based on end user functional view of the system. The MK II Method (ISO/IEC 20968 Software engineering—Mk II Function Point Analysis—Counting Practices Manual) is one of five currently recognized ISO standards for Functionally sizing software.
of the software are identified and each one is categorized into one of there types: inputs, exits and objects. In order to determine functional size of system these functional requirements are counted.
Size of application is sum of sizes of logical transactions - each transaction is counted once even though it may be executed from more than one point in the application.
Size = Wi*∑Ni+ We*∑Ne + Wo*∑No
In the equation ∑Ni, ∑Ne and ∑No are total numbers of unique inputs, exits ad objects within the system. Currently recommended values for weighting coefficients are Wi = 0.58, We = 1.66, and Wo = 0.26.
Introduction
The MK II Method were defined by Charles Symons in book published in 1991. UK Software Metrics Association is now responsible for the method and its continuing development. The functional user requirementsFunctional requirements
In software engineering, a functional requirement defines a function of a software system or its component. A function is described as a set of inputs, the behavior, and outputs ....
of the software are identified and each one is categorized into one of there types: inputs, exits and objects. In order to determine functional size of system these functional requirements are counted.
Define the Boundary of the Count
Boundary of system represents logical line that separates users from a system. It is used to determine logical transactions such as inputs and exits that crosses boundary during the interaction between user and system.Identify the Logical Transactions
Logical transactions are elementary processes triggered by unique events. Transactions consist of input side that enters information across the boundary, processing that maintains the data and output that returns information back to user. Each transaction must leave system in consistent state. There are two types of logical transactions that crosses a boundary:- Inputs - processes that enters information in the system. Examples of these transactions are creating new records, updating records or deleting records.
- Exits - processes that takes information from the system and shows them to user. Examples of these transactions could be reports, notifications or searches.
Size of application is sum of sizes of logical transactions - each transaction is counted once even though it may be executed from more than one point in the application.
Identify and Categorise Data Entity Types
Data entity types are logical data structures that contains information meaningful to the user. In MarkII method there is only one type of data entity types - Objects. Objects must be correctly identified so they can be counted.Count the Input Data Element Types, the Data entity Types Referenced, and the Output Data Element Types
Count the Functional Size
Once the transactions and objects in the system are identified, they can be counted in order to find functional size of the system. Functional size of the system is represented as weighted counts of input/exit transactions and objects within the boundary of the system. Size can be expressed as following:Size = Wi*∑Ni+ We*∑Ne + Wo*∑No
In the equation ∑Ni, ∑Ne and ∑No are total numbers of unique inputs, exits ad objects within the system. Currently recommended values for weighting coefficients are Wi = 0.58, We = 1.66, and Wo = 0.26.
See also
- Function pointFunction pointA function point is a unit of measurement to express the amount of business functionality an information system provides to a user. The cost of a single unit is calculated from past projects....
- Software development effort estimationSoftware development effort estimationSoftware development efforts estimation is the process of predicting the most realistic use of effort required to develop or maintain software based on incomplete, uncertain and/or noisy input...
- Software SizingSoftware SizingSoftware sizing is an activity in software engineering that is used to estimate the size of a software application or component in order to be able to implement other software project management activities...