Question

Cincinnati Paint Company sells quality brands of paints through hardware stores throughout the United States. The company maintains a large sales force who call on existing customers and look for new business. The national sales manager is investigating the relationship between the number of sales calls made and the miles driven by the sales representative. Also, do the sales representatives who drive the most miles and make the most calls necessarily earn the most in sales commissions? To investigate, the vice president of sales selected a sample of 25 sales representatives and determined: • The amount earned in commissions last month (7 • The number of miles driven last month (x1) • The number of sales calls made last month (x2) The information is reported below. Commissions ($800) 23 Commissions (see) 39 Calls 188 218 105 162 39 24 154 Calls Driven 68 2,372 30 2,229 1362 ,733 1 80 3,353 7 7 2,291 186 3,451 1033 , 117 1433 , 343 200 2,843 156 2,626 50 2,122 46 2,222 2 25 3,466 Driven 3,291 3,103 2,123 2,794 3,209 2,289 2,850 2,934 15 30 26 132 94 42 32 2,830 13 47 Click here for the Excel Data File Develop a regression equation including an interaction term. (Negative amount should be indicated by a minus sign. Round your answers to 3 decimal places.) Commissions + Calls +

Answer 1

Output using excel :

SUMMARY OUTPUT
Regression Statistics
Multiple R	0.97691069
R Square	0.95435451
Adjusted R Square	0.94783372
Standard Error	2.29204977
Observations	25
ANOVA
	df	SS	MS	F	Significance F
Regression	3	2306.637	768.8789	146.3558	3.11E-14
Residual	21	110.3233	5.253492
Total	24	2416.96
	Coefficients	Standard Error	t Stat	P-value	Lower 95%	Upper 95%
Intercept	-3.5292365	8.110462	-0.43515	0.667896	-20.3959	13.33739
Calls	0.18649539	0.061442	3.035305	0.006292	0.05872	0.314271
Driven	0.00654214	0.003295	1.98522	0.060334	-0.00031	0.013395
x1x2	-0.00001791	2.2E-05	-0.81431	0.424607	-6.4E-05	2.78E-05

Regression equation:

Commissions = (-3.529) + (0.186) Calls + (0.007) Miles + (0.00002) x1x2

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	Coefficients	Standard Error	t Stat	P-value
Intercept	-3.529	8.110	-0.435	0.668
Calls	0.186	0.061	3.035	0.006
Miles	0.007	0.003	1.985	0.060
x1x2	0.000018	0.000022	-0.814	0.425

Value of test statistic: -0.814

As p-value > 0.05, we reject the null hypothesis. There is no significant interaction between the number of calls and the miles driven.