Question

A marketing organization wishes to study the effects of four sales methods on weekly sales of a product. The organization employs a randomized block design in which three salesman use each sales method. The results obtained are given in the following table, along with the output of a randomized block ANOVA of these data.

Salesman, j
Sales Method, i	A	B	C
1	32	29	30
2	32	30	28
3	28	25	23
4	24	24	23

Analysis of Variance
Source	DF	Sum of Squares	Mean Square	F Ratio
Model	5	119.33333	23.8667	19.5273
Error	6	7.33333	1.2222	Prob > F
C. Total	11	126.66667	25.0889	0.0012*

Effect Tests
Source	Nparm	DF	Sum of Squares	F Ratio	Prob > F
Method	3	3	100.666670	27.4545	0.0007*
Salesman	2	2	18.666670	7.6364	0.0224*

Least Squares Means Estimates
Method	Estimate	Salesman	Estimate
1	30.333333	A	29.000000
2	30.000000	B	27.000000
3	25.333333	C	26.000000
4	23.666667

Tukey HSD All Pairwise Comparisons

Quantile = 3.46171, Adjusted DF = 60, Adjustment = Tukey

Method -Method		Difference	Std Error	t Ratio	Prob>|t|	Lower 95%	Upper 95%
1	2	0.333333	0.9026709	0.37	0.9812	−2.79145	3.458110
1	3	5.000000	0.9026709	5.54	0.0059*	1.87522	8.124780
1	4	6.666667	0.9026709	7.39	0.0013*	3.54189	9.791450
2	3	4.666667	0.9026709	5.17	0.0083*	1.54189	7.791450
2	4	6.333333	0.9026709	7.02	0.0017*	3.20855	9.458110
3	4	1.666667	0.9026709	1.85	0.3397	−1.45811	4.791450

Use Tukey simultaneous 95 percent confidence intervals to make pairwise comparisons of the sales method effects on mean weekly sales. Which sales method(s) maximize mean weekly sales? (Round your answers to 3 decimal places. Negative amounts should be indicated by a minus sign.)

Method 1-Method 2:

Method 1-Method 3:

Method 1-Method 4:

Method 2-Method 3:

Method 2-Method 4:

Method 3-Method 4:

Answer 1