# Question

Mike Wilde is president of the teachers’ union for Otsego School District. In preparing for upcoming negotiations, he would like to investigate the salary structure of classroom teachers in the district. He believes there are three factors that affect a teacher’s salary: years of experience, a rating of teaching effectiveness given by the principal, and whether the teacher has a master’s degree. A random sample of 20 teachers resulted in the following data.

a. Develop a correlation matrix. Which independent variable has the strongest correlation with the dependent variable? Does it appear there will be any problems with multicollinearity?

b. Determine the regression equation. What salary would you estimate for a teacher with 5 years’ experience, a rating by the principal of 60, and no master’s degree?

c. Conduct a global test of hypothesis to determine whether any of the regression coefficients differ from zero. Use the .05 significance level.

d. Conduct a test of hypothesis for the individual regression coefficients. Would you consider deleting any of the independent variables? Use the .05 significance level.

e. If your conclusion in part (d) was to delete one or more independent variables, run the analysis again without those variables.

f. Determine the residuals for the equation of part (e). Use a stem-and-leaf chart or a histogram to verify that the distribution of the residuals is approximately normal.

g. Plot the residuals computed in part (f) in a scatter diagram with the residuals on the Y-axis and the yˆ values on the X-axis. Does the plot reveal any violations of the assumptions ofregression?

a. Develop a correlation matrix. Which independent variable has the strongest correlation with the dependent variable? Does it appear there will be any problems with multicollinearity?

b. Determine the regression equation. What salary would you estimate for a teacher with 5 years’ experience, a rating by the principal of 60, and no master’s degree?

c. Conduct a global test of hypothesis to determine whether any of the regression coefficients differ from zero. Use the .05 significance level.

d. Conduct a test of hypothesis for the individual regression coefficients. Would you consider deleting any of the independent variables? Use the .05 significance level.

e. If your conclusion in part (d) was to delete one or more independent variables, run the analysis again without those variables.

f. Determine the residuals for the equation of part (e). Use a stem-and-leaf chart or a histogram to verify that the distribution of the residuals is approximately normal.

g. Plot the residuals computed in part (f) in a scatter diagram with the residuals on the Y-axis and the yˆ values on the X-axis. Does the plot reveal any violations of the assumptions ofregression?

## Answer to relevant Questions

A consumer analyst collected the following data on the screen sizes of popular LCD televisions sold recently at a large retailer:a. Does there appear to be a linear relationship between the screen size and the price?b. ...Many regions along the coast in North and South Carolina and Georgia have experienced rapid population growth over the last 10 years. It is expected that the growth will continue over the next 10 years. This has motivated ...Refer to the Real Estate data, which report information on homes sold in Goodyear, Arizona. Use the selling price of the home as the dependent variable and determine the regression equation with number of bedrooms, size of ...The following hypotheses are given.H0: π ≤ .70H1: π > .70A sample of 100 observations revealed that ρ = .75. At the .05 significance level, can the null hypothesis be rejected?a. State the decision rule.b. Compute the ...The safety director of a large steel mill took samples at random from company records of minor work-related accidents and classified them according to the time the accident took place.Using the goodness-of-fit test and the ...Post your question

0