cost23 1 Question of the Day u Which of the following things measure the “size” of the project in terms of the functionality that has to be provided in the project? u inputs, outputs, classes/objects, methods, files, reports, commands, records u What other things might be counted?

cost23 2 Cost Estimation Using Function Points

cost23 3 Function Points u Attempting to measure “functionality” u widely used in business applications u IFPUG

cost23 4 Program Features u outputs u inquiries u inputs u files u interfaces

cost23 5 Pressman, Soft Eng, 5th Ed u Outputs – “Each user output that provides application- oriented information to the user is counted. In this context output refers to reports, screens, error messages, and so on. Individual data items within a report are not counted separately”

cost23 6 Pressman, Soft Eng, 5th Ed u Inputs – “Each user input that provides distinct application-oriented data to the software is counted. Inputs should be distinguished from inquiries, which are counted separately” u Inquiries – “An inquiry is defined as an on-line input that results in the generation of some immediate software response in the form of an on-line output. Each distinct inquiry is counted.”

cost23 7 Pressman, Soft Eng, 5th Ed u Files – “Each logical master file (I.e. a logical grouping of data that may be one part of a large database or a separate file), is counted” u External interfaces – “All machine readable interfaces (e.g. data files on tape or disk) that are used to transmit information to another system are counted.”

cost23 8 Dreger, FPA, 1989 u “A function point is defined as one end-user business function” u “business functions made available to the user are identified” u “outputs are items of business information processed by the computer for the end user”

cost23 9 Dreger, FPA, 1989 u Inquiries “are direct inquiries into a data base or master file that look for specific data, use simple keys, require immediate response and perform no update functions” u “Inputs are items of business data sent by the user to the computer for processing and to add, change, or delete something.” u “Files are data stored for an application, as logically viewed by the user”

cost23 10 Dreger, FPA, 1989 u Outputs – “count each of the outputs leaving the context diagram ‘area under study’ at the lowest (greatest detail) level of the logical … data flow diagram system” – count separately if different format or different processing u Dreger says detail lines and total lines are different, ifpug says no

cost23 11 Dreger, FPA, 1989 u Inputs – “count each unique user data or control input that enters the application boundary and also updates (adds to, changes, or deletes from) a logical internal file, data set, table or independent data item.” – “count as one input each uniquely formatted or processed portion...”

cost23 12 Dreger, FPA, 1989 u Files –“count each major logical group of user data or control information” u Interfaces –“count as one interface each major logical.. file or other logical group of user-approved data or control information within the application boundary that is set to, shared with, or received from another application.”

cost23 13 Weights for features u simple average complex u outputs u inquiries u inputs u files u interfaces

cost23 14 TTYP1 u Identify the inputs, outputs, enquiries, files and interactions for the following task. u A doctor’s appt_system makes appointments for patients. Patients select type of visit and asks for specific time or next available or times on a specific date. System offers choices and allows patient to select and/or confirm appointment.

cost23 15 Questions u Does the system require reliable backup and recovery? u Are data communications required? u Are there distributed processing functions? u Is performance critical? u Will the system run in an existing, heavily utilized operational environment?

cost23 16 Questions u Does the system require on-line data entry? u Does the on-line data entry require the input transaction to be built over multiple screens or operations? u Are the master files updated on-line? u Are the inputs, outputs, files, or inquiries complex? u Is the internal processing complex?

cost23 17 Questions u Is the code designed to be reusable? u Are conversion and installation included in the design? u Is the system designed for multiple installations in different organizations? u Is the application designed to facilitate change and ease of use by the user?

cost23 18 Adjusted Function Points u FP = FP unadjusted * ( * (sum of ratings ) )

cost23 19 TTYP2 u What if function points are not equal in effort? u How could you adjust your counting?

cost23 20 For Thursday u Find the article

cost23 21 For Thursday u Find and read the following article u “Critical Success Factors in Software Projects” by John Reel in IEEE Software, May/June 1999 u Use IEEExplore (Hale Library, Databases, Engineering, search for author John Reel)