Pulmonary Hypertension. Inthe paper ‘‘Persistent Pulmonary Hypertension of the Neonate and Asymmetric Growth Restriction”

(Obstetrics & Gynecology, Vol. 91, No. 3, pp. 336–341), M. Williams et al. reported on a study of characteristics of neonates. Infants treated for pulmonary hypertension, called the PH group, were compared with those not so treated, called the control group. One of the characteristics measured was head circumference. The following data, in centimeters (cm), are based on the results obtained by the researchers.

PH Control 33.9 35.1 35.2 35.6 36.7 35.1 36.0 33.4 34.5 33.4 31.3 33.5 35.8 36.3 37.9 31.3 34.3 33.1 32.4 35.1 33.6 32.5 32.9 31.8 34.1 35.2 34.8 34.5 36.3 34.2 31.6 31.9 31.9 32.8 34.0 Do the data provide sufficient evidence to conclude that variation in head circumference differs among neonates treated for pulmonary hypertension and those not so treated? Perform an F-test at the 5% significance level. (Note: s1 = 1.907 and s2 = 1.594.)