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Exam2 Review. Q1 - Parnas. Parnas discussed that software is difficult because failures are not independent, functions are not continuous, and interpolation is not useful. Explain what he meant by each of these ideas and how each of these ideas influence the testing of safety-critical software.
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Exam2 Review 841f07exam2review24nov27
Q1 - Parnas Parnas discussed that software is difficult because failures are not independent, functions are not continuous, and interpolation is not useful. Explain what he meant by each of these ideas and how each of these ideas influence the testing of safety-critical software. 841f07exam2review24nov27
Q2 – van der Meulen • (10 pts) describe his use of equivalence classes. How were they determined? • b. (30 pts) In van derMeulen’s article, he mentioned using the diversity of software programs to improve reliability. Assume that there are 3 programs (Pa, Pb, Pc) that each have failure probabilities of .2 Their failures sets (A,B,C) overlap such that size of AB(where both Pa and Pb fail) is .5 of A and .5 of B. Pc is independent of A and/or B. Find the probability of failure of a voting system that uses these 3 programs. 841f07exam2review24nov27
Q3 Hamlet Consider an aquarium that has to make a decision about adding water to their main pool based on the amount of daily rainfall. If they don’t add enough water and there is not adequate rain, the fish die which is very expensive besides being cruel. If they add too much water, it is wasted which costs some money. The inputs are the expected daily rainfall in inches, the water surface area of the pool, and the expected evaporation amount for the next 24 hours. The output of the analysis program is a number that is how much water needs to be added. 841f07exam2review24nov27
Q3 part A • (15 pts) Write Term Rewriting Rules that are true and could be used to change the input values into equivalent sets of input values. Justify that these rules do produce diverse executions. 841f07exam2review24nov27
Q3 part B • (20 pts) Explain how the voting system could be used or modified to improve the fish life expectancy. 841f07exam2review24nov27
Q3 part C • ( 15 pts) How could you test Hamlet’s approach sufficiently to justify to your boss the use of this approach. 841f07exam2review24nov27
Q4a Bertolino • (15 pts) Explain each of the four dreams. Evaluate whether they are practical and whether they are achievable. 841f07exam2review24nov27
Q4b Bertolino • (10 pts) Explain Bertolino’s view of the effect of OO on software testing (or why is OO testing not easier). 841f07exam2review24nov27
Q4c Bertolino • (5 pts) Explain the following diagram. What are the columns, rows, significance of the placements of items, significance of items that span multiple rows/columns. 841f07exam2review24nov27
Remaining Lectures • Thurs, 11/29 – Zachariah paper • Tues, 12/4 – Briand, “A Critical Analysis of Empirical Research in Software Testing” • Thurs, 12/6 – finish Briand, review for final • Wed, 12/12 2:00-3:50 150 pts 841f07exam2review24nov27