In: Math
Breast-feeding mothers secrete calcium into their milk. Some of the calcium may come from their bones, so mothers may lose bone mineral. Researchers measured the percent change in mineral content of the spines of 47 mothers during three months of breast-feeding. The sample mean is -3.587%. Let us assume that these 47 women as an SRS from the population of all nursing mothers. Suppose that the percent change in this population has standard deviation 2.5%.
The hypothesized value μ0=−2.7% falls inside this confidence interval. Carry out the z-test for H0:μ=−2.7% against the two-sided alternative. Show that the test is not significant at the 1% level.