“…For completeness, we also introduce the RANDOM strategy that simply requires the execution of all changed statements. 1 To analyze change-testing strategies, including BR, DU, and the strategies presented in the next section, we use the PIE model [19] adapted for changes [15]: a change reveals a difference in the output if and only if the change executes, infects the state (i.e., creates an infection-a difference in the program state), and the infection propagates to the output. In the example of Figure 1, change ch1 is executed always (satisfying the execution condition), the state is infected if a does not equal 0, and the infection propagates to the output if, for example, line 9 is reached such that r equals p (i.e., when c is even), so that line 9 prints -a instead of a.…”