Question 1
Concerning the simple linear regression model, SST can be expressed as:
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SSA + SSB + SSE.
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SSR + SSE.
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SST + SSR.
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SST + SSR + SSE.
Question 2
Consider the following regression analysis for predicting sales per week from intelligence and extroversion scores:
The regression equation is
Sales/Week = 994 + 8.22 Intelligence + 49.7 Extroversion
Term Coef SE Coef T-Value P-Value
Constant 994 788 1.26 0.224
Intelligence 8.22 7.01 1.17 0.257
Extroversion 49.7 19.6 2.53 0.021
S R-sq R-sq(adj) R-sq(pred)
332.069 35.26% 27.65% 10.66%
Analysis of Variance
Source DF Adj SS Adj MS F-Value P-Value
Regression 2 1021166 510583 4.63 0.025
Error 17 1874584 110270
Total 19 2895750
What proportion of the variability in sales per week is explained by the model?
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0.1066
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0.224
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0.3526
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0.021