Explore BrainMass
Share

# Regression analysis

This content was STOLEN from BrainMass.com - View the original, and get the already-completed solution here!

This is a forecasting and regression analysis problem that requires the regression analysis to be done to find the slope and intercept. Also adjust the chart to show the Y variables in excel 2007. Please explain that also.

Carpet City wants to develop a means to forecast its carpet sales. The store manager believes that the store's sales are directly related to the number of new housing starts in town. The manager has gathered data from county records on the monthly house construction permits and from store records on the monthly sales.
a. Develop a linear regression model for these data and forecast carpet sales if 30 constructive permits for new homes are filed.
b. Determine the strength of the causal relationship between monthly sales and new home construction by using correlation.

The data are given in the attachment.

© BrainMass Inc. brainmass.com October 25, 2018, 1:26 am ad1c9bdddf
https://brainmass.com/math/interpolation-extrapolation-and-regression/regression-analysis-263021

#### Solution Summary

The solution provides step by step method for the calculation of regression analysis. Formula for the calculation and Interpretations of the results are also included.

\$2.19
See Also This Related BrainMass Solution

## Statistics Problems - Regression Analysis, Autocorrelation, Multicollinearity

1. Suppose an appliance manufacturer is doing a regression analysis, using quarterly time-series data, of the factors affecting its sales of appliances. A regression equation was estimated between appliance sales (in dollars) as the dependent variable and disposable personal income and new housing starts as the independent variables. The statistical tests of the model showed large t-values for both independent variables, along with a high r2 value. However, analysis of the residuals indicated that substantial autocorrelation was present.

a. What are some of the possible causes of this autocorrelation?

b. How does this autocorrelation affect the conclusions concerning the significance of the individual explanatory variables and the overall explanatory power of the regression model?

c. Given that a person uses the model for forecasting future appliance sales, how does this autocorrelation affect the accuracy of these forecasts?

d. What techniques might be used to remove this autocorrelation from the model?

2. Suppose the appliance manufacturer discussed in Exercise 1 also developed another model, again using time-series data, where appliance sales was the dependent variable and disposable personal income and retail sales of durable goods were the independent variables. Although the r2 statistic is high, the manufacturer also suspects that serious multicollinearity exists between the two independent variables.

a. In what ways does the presence of this multicollinearity affect the results of the regression analysis?

b. Under what conditions might the presence of multicollinearity cause problems in the use of this regression equation in designing a marketing plan for appliance sales?

View Full Posting Details