Analyzing and Interpreting Test Results - Software Testing: Testing Across the Entire Software Development Life Cycle - page 198

Figure 12.16

Prior development project defect tracking log

Write down the gunsight x -coordinate as the number of weeks in the project, in
this case week 10. Write down the gunsight y -coordinate as the peak discovery rate,
in this case approximately 750 defects. The Rayleigh curve formula requires any two
of the following three inputs:

1.
2.
3.

peak defect discovery rate
project week that the peak defect discovery occurred
total number of defects discovered

Notice that you have inputs 1 and 2 from the prior project curve gunsight; further-
more, you would like the Rayleigh curve to tell you input 3. Figure 12.17 shows you
the results of your inputs to the Rayleigh curve formula plotted on the same axis as
your prior project defect curve.

Figure 12.17 Prior development project defect tracking log compared to a calibrated Rayleigh curve