30 Success/failure of software reuse. The PROMISE Software Engineering Repository, hosted by the University of Ottawa, is a collection of publicly available data sets to serve researchers in building prediction software models.

A PROMISE data set on software reuse, saved in the SWREUSE file, provides information on the success or failure of reusing previously developed software for each in a sample of 24 new software development projects.

( Data source: IEEE Transactions on Software Engineering , Vol. 28, 2002.) Of the 24 projects, 9 were judged failures and 15 were successfully implemented.

a. Identify the experimental units for this study.

b. Describe the population from which the sample is selected.

c. What is the variable of interest in the study? Is it quantitative or qualitative?

d. Critically evaluate the statement “ Since 15>24 = .625, it follows that 62.5% of all new software development projects will be successfully implemented.”