Question

3. "Parental Sensitivity to Infant Cues: Similarities and Difference Between Mothers and Fathers" by MV Graham reports a study of parental empathy for sensitivity cues and baby temperament (higher scores means more empathy). Let xi be a random variable that represents the score of a mother on an empathy test. Let x2 be the empathy score of a father. A random sample of 27 mothers gave a sample mean ofxi- 73. Another random sample of 36 fathers gave X2 = 64. Assume that ?| = 11.2 and ?,-12.0. (a) Which distribution, normal or Student's t, do we use to approximate thex1 -x2 distribution? Explain. . (b) Let M be the population mean of X1 and letHz be the population mean of X2. Find a 92% confidence interval for -H2. What can we conclude?

Answer 1