Engineers are examining certain boats. They suspect that the diameters of a certain part of the crankshafts are too small on average. The mean diameter is supposed to be 49.72 mm. Accordingly, the engineers decide to test the hypothesis H0 : μ ≥ 47.92 against H1 : μ <>
Crankshaft diameters are known to be normally distributed. Fourteen (14) measurements yield a sample mean diameter of 49.714 mm and a sample standard deviation of 0.021 mm.
a)Calculate the value of the test statistic (i.e., the z -score or t -score) for this hypothesis test. (do NOT round answer - give all answers to 5 decimal places)
b)MCQ - Which option is the best definition of “P-value of an hypothesis test?”? (pick only 1)
1. The probability that the null hypothesis is true
2. The probability that the null hypothesis is false
3. The probability of rejecting the null hypothesis, whether this hypothesis is true or not
4. The probability of getting a sample mean that disagrees with the null hypothesis more than the one actually obtained, assuming that the null hypothesis is true