Question

The quality control team wish to investigate the rollover rates between two types of vehicles, A and B. Among 1200 tests on each type, 39 of the ‘A’s and 33 of the ‘B’s failed the test. Can we conclude that vehicle A has a higher rollover rate than vehicle B? Assume ? = 0.05.

a. Write the appropriate hypothesis.

b. Use P-value approach for hypothesis testing.

c. Use z-test for hypothesis testing.

d. Use confidence interval for hypothesis testing.

e. Clearly write your conclusion.

f. If the true rollover rates are ??′ = 0.035 and ??′ = 0.025, what is the type II error?

g. If the true rollover rates are ??′ = 0.035 and ??′ = 0.025, what is the minimum sample size needed to detect that difference with 99% probability?

Answer 1

Ans a)

Calculation

Ans b)

Ans c)

Ans d)

Ans e)