Suppose that the true mean birth-weight for the low- SES babies is 120 oz, the true standard deviation is 24 oz, and the distribution of birth-weights is normal. Generate 100 random samples of size 100 each from this distribution. Perform the appropriate t test for each sample to test the hypothesis stated in Example 7.2, and compute the proportion of samples for which we declare a significant difference using a 5% level of significance with a one-tailed test.

Simulation

Consider the birth-weight data in Example 7.2.