Each of the following problems uses a procedure that can be found in the PHStat menu, under Confidence Intervals, Sample Size, or One Sample Tests. Each question relies on the data in your Housing and Donations datafile.
A. Using PHStat/Excel, estimate the population mean level of annual charitable donations at the 99% confidence level. Remember: you do NOT know what the standard deviation of the population of donations is. (5 points)
B. Using PHStat/Excel, estimate the population proportion of all respondents who think their housing situation is “Comfortable and Safe” at the 95% confidence level. (5 points)
C. If we were to conduct a survey to determine the mean annual housing expenses for ALL households in the US, how large a sample of cities should we take if we want the point estimate (sample mean) to be within $1000 of the true population mean, at the 95% confidence level? Use PHStat/Excel to determine this sample size. (5 points)
D. Test the hypothesis that the population mean level of annual charitable donations is more than $1000 at the 0.05 significance level (alpha). Think carefully about what the null hypothesis is and whether this is a two tail, lower tail, or upper tail test. (5 points)