APFD for this is as follows.
APFD = 1 – ( ( 3 + 2 + 1 + 3 + 1 )/ ( 5 * 5 ) + $\frac{1}{2*5}$
= 1 - $\frac{10}{25} + \frac{1}{10}$
= $\frac{15}{25} + \frac{1}{10}$
= $\frac{3}{5} + \frac{1}{10}$
= $\frac{35}{50} = \frac{7}{10}$
= 0.7
For measuring effectiveness of priotized test suite, the rate at fault detection criteria can be taken into consideration.
The average percentage of faults detected (APFD) metric that measures the weighted average of the percentage of faults detected during execution of test suite.
APFD is a metric to detect how quickly a test suite identifies the faults.
APFD is calculated as
APFD = 1 – ( ( TF 1 + TF 2 + …..+ TFn) / nm ) + $\frac{1}{2n}$
Where,
TFi = is the position of first test in the test suite T that exposes fault I
M = is the total no. of faults exposed in the system or module under T
N = is the total no. of test cases in T.