1. Standardized measures seem to indicate that the average level of anxiety has increased gradually over the past 50 years. In the 1950s, the average score on the child manifest anxiety scale was µ=15.1. A sample of n=16 of today's children produces a mean score of M=23.3 with SS=240.
a. based on the sample, make a point estimate of the population mean anxiety score for today's children.
b. make a 90% confidence interval estimate of today's population mean.
2. Doctor visits during past year
Control group dog owners
12 8
10 5
6 9
9 4
15 6
12
14
Use these data to estimate how much difference there is in the number of doctor visits for people with dogs compared to those without.
a. Make a point estimate of the population mean difference.
b. Make a 90% confidence interval estimate of the mean difference.