Birth Length of Stay Refer to Data Set 3 “Births” in Appendix B.

a. Use the lengths of stay (days) for the 205 girls to construct a 95% confidence interval estimate of the standard deviation of the population from which the sample was obtained. For critical values, use x2 L = 166.337 and x2 R = 245.449. Does the distribution of those data appear to be approximately normal? How does that affect the results?

b. Repeat part

(a) using the 195 boys and, for critical values, use x2 L = 157.321 and x2 R = 234.465.

c. Compare the results from part

(a) and part (b).