A copy company uses ten photocopy machines—machines 1 to 5 are model A and machines 6 to 10 are model B. To determine which model to purchase in the future, office managers tabulated the average number of errors per day that each machine made last month, resulting in the following data. You are hired for the statistical consulting on the decision. What would be your advice on the future decision on purchasing a new copy machine?
Conduct a formal significance test and specify the four steps of hypothesis testing. Hint: you can use EXCEL to obtain the pertinent statistics, but you will also need to lay out the formulas.
12. Seven women were asked their opinions about the ideal number of children in a family. The ideal numbers of children before and after they got married are shown in the following data table. Conduct a formal significance test and specify the four steps of hypothesis testing. Hint: you can use EXCEL to obtain the pertinent statistics, but you will also need to lay out the formulas.
Extra credits: calculate the observed t-value and 95% confidence interval using the data, and confirm your results with the EXCEL output you chose.
