Question

In: Statistics and Probability

We're studying the diameter of a certain type of bolt. The mean calculated from a sample...

We're studying the diameter of a certain type of bolt. The mean calculated from a sample of 42 bolts is 2.48 cm and the standard deviation is 0.10 cm. We're testing the hypothesis
H0 : mu=2.50cm
H1 : mu doesn’t equal 2.50cm

a) Calculate the second species error with a significance level of 5% when the mean is 2.45 cm.

b) Determine the sample size to be taken to reject a batch of bolts with a diameter of 2.52 with a probability of 0.25.

Solutions

Expert Solution

The critical value and the p value is obtained from STATKEY (image attached for reference). For the first problem we calculate the probability of Type II error. For the second problem, the sample size is obtained from the z score formula mentioned.

orchestra answered 2 years ago
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