Question

The owner of a moving company usually has her most experienced manager predict the total number of labor hours required to complete a move. While useful, the owner is interested in a more accurate method of predicting the number of labor hours required. As a preliminary effort, data was collected on the number of work hours required to complete a move, number of cubic feet moved, the number of large pieces, and if an elevator was present.

0 eeeeeeee o e e e e e e e o o e e e e e e e oeo EYYNNYYYYYYYYYYYYNYYYYYYYNNYYYYYYYNYN 7 3222132161443232222543323333434325 0) 2706705462957 1509709584499 3539288337642507553767556044293 51 0 5 0 1 6 17 2 455590250250588/155591257245-4078555 2 3. 2 2 2225174 9. 6. 333232421 2. .7 9. 1222124222 01234567 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 567

How much correlation is there between the variables?

How much of the variability in strength is explained by the predictors?

Estimate the number of hours required when 325 cubic feet are moved with 3 large pieces of furniture and no elevator is present.

Estimate the number of hours required when 425 cubic feet are moved with 7 large pieces of furniture and an elevator is present.

Estimate the number of hours required when 375 cubic feet are moved with 2 large pieces of furniture and no elevator is present.

Answer 1

excel o/p for regression using data analysis tool g/n below -

SUMMARY OUTPUT
Regression Statistics
Multiple R	0.980588
R Square	0.961552
Adjusted R Square	0.957948
Standard Error	3.05571
Observations	36
ANOVA
	df	SS	MS	F	Significance F
Regression	3	7472.642	2490.881	266.7649	1.03E-22
Residual	32	298.7956	9.337362
Total	35	7771.438
	Coefficients	Standard Error	t Stat	P-value	Lower 95%	Upper 95%	Lower 95.0%	Upper 95.0%
Intercept	2.990449	1.907844	1.56745	0.126846	-0.8957	6.876599	-0.8957	6.876599
feet	0.025598	0.003764	6.801469	1.09E-07	0.017932	0.033264	0.017932	0.033264
large	5.042393	0.721561	6.988175	6.43E-08	3.572622	6.512164	3.572622	6.512164
elevator	-6.76828	1.382064	-4.89723	2.68E-05	-9.58345	-3.95311	-9.58345	-3.95311

correlation is 0.9806

R Square   0.9616

so, 96.16% of variability in strength is explained by the predictors.

Estimate the number of hours required when 325 cubic feet are moved with 3 large pieces of furniture and no elevator is present

estimated hours = 2.99*feet + 5.042 * large - 6.768*elevator

so, estimated hours = 2.99*325 + 5.042*3 - 6.768*0 = 26.44

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Estimate the number of hours required when 425 cubic feet are moved with 7 large pieces of furniture and an elevator is present.

estimated hours = 2.99*feet + 5.042 * large - 6.768*elevator

estimated hours = 2.99*425 + 5.042 * 7 - 6.768*1 = 42.40

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Estimate the number of hours required when 425 cubic feet are moved with 7 large pieces of furniture and an elevator is present.

estimated hours = 2.99*feet + 5.042 * large - 6.768*elevator

estimated hours = 2.99*375 + 5.042 * 2 - 6.768*0 = 22.67