Dr Kelly is a developmental psychologist who studies the eff

Dr. Kelly is a developmental psychologist who studies the effect of income on family dynamics. In one of her studies, she examined whether low SES (i.e., income below the poverty line) would affect parenting quality. To address this research question, she recruited 45 parents who are at or below the poverty line and asked them to complete the Parental Competence Scale-Revised (PCSR). On this measure, 1 indicates parents being extremely incompetent, and 7 indicates parents being extremely competent. In the general population of United States families, parents score 4.65 on this measure. Below is the data collected from the 45 parents with a child with cancer in the study conducted by Dr. Watson.

3, 1, 7, 6, 5, 4, 5, 3, 6, 5, 1, 3, 4, 2, 4, 2, 3, 4, 6, 5, 2, 4, 4, 6, 4, 1, 2, 6, 1, 6, 5, 2, 6, 6, 5, 6, 4, 3, 5, 7, 7, 3, 4, 2, 5

1. report results in APA format

Solution

The null hypothesis is mu=4.65 and the alternative hypothesis is mu is not equal to 4.65. It is a two-tailed test. Assume that the significant level a=0.05, the critical values are Z(0.025)=-1.96 or 1.96 (from standard normal table). The rejetion regions are if Z<-1.96 or Z>1.96, we reject the null hypothesis. Otherwise, we do not reject the null hypothesis. The test statistic is Z=(xbar-mu)/(s/vn) = (4.111-4.65)/(1.76/sqrt(45)) =-2.05. Since Z=-2.05 is less than -1.96, we reject the null hypothesis. So we can conclude that low SES (i.e., income below the poverty line) would affect parenting quality