Business Stats Exam 4 Review questions with accurate || || || || || || || ||
detailed solutions ||
Excel and virtually all other statistical packages report the p-value ________. - ✔✔for a two-
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tailed test that assesses whether the regression coefficient differs from zero
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The accompanying table shows the regression results when estimating y = β0 + β1x + ε.
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Coefficients Standard Error T-Stat P-Value || || || ||
Intercept 0.083 3.56 0.02 0.9822 || || || ||
X 1.417 0.63 2.25 0.0745
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Is x significantly related to y at the 5% significance level? - ✔✔No, because the p-value of
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0.0745 is greater than 0.05.
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A marketing analyst wants to examine the relationship between sales (in $1,000s) and
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advertising (in $100s) for firms in the food and beverage industry and so collects monthly
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data for 25 firms. He estimates the model:
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Sales = β0 + β1 Advertising + ε. The following table shows a portion of the regression
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results.
Coefficients Standard Error T-Stat P-Value || || || ||
Intercept 40.10 14.08 2.848 0.0052 || || || ||
Advertising 2.88 1.52 -1.895 0.0608 || || || ||
,2
Which of the following are the competing hypotheses used to test whether Advertising is
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significant in predicting Sales? - ✔✔H0:β1 = 0; HA:β1 ≠ 0.
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A marketing analyst wants to examine the relationship between sales (in $1,000s) and
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advertising (in $100s) for firms in the food and beverage industry and so collects monthly
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data for 25 firms. He estimates the model:
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Sales = β0 + β1 Advertising + ε. The following table shows a portion of the regression
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results.
Coefficients Standard Error T-Stat P-Value || || || ||
Intercept 40.10 14.08 2.848 0.0052 || || || ||
Advertising 2.88 1.52 -1.895 0.0608 || || || ||
When testing whether Advertising is significant at the 10% significance level, the conclusion
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is to ________. - ✔✔reject H0; we can conclude advertising is significant
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A sports analyst wants to exam the factors that may influence a tennis player's chances of
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winning. Over four tournaments, he collects data on 30 tennis players and estimates the
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following model: ||
Win = β0 + β1 Double Faults + β2 Aces + ε, where Win is the proportion of winning, Double
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Faults is the percentage of double faults made, and Aces is the number of aces. A portion
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of the regression results are shown in the accompanying table.
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Df ss ms f significance f
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Regression 2 1.24 .620 41.85 5.34E-09 || || || || ||
Residual 27 0.40 .015 || || ||
Total 29 1.64 || ||
Coefficients Standard Error T-Stat P-Value Lower 95 Upper 95 || || || || || || || ||
Intercept .451 .080 5.646 5.4E-06 .287 .614|| || || || || ||
, 2
Double -.007 .0024 -2.875 .0078 -.012 -.002
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Aces .015 .003 4.65 7.8E-05 .008 .023
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When testing whether the explanatory variables jointly influence the response variable, the
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null hypothesis is ________. - ✔✔H0:β1 = β2 = 0
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The accompanying table shows the regression results when estimating y = β0 + β1x1 + β2x2
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+ β3x3 + ε.
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Df ss ms f significance f
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Regression 3 453 151 5.03 .0030 || || || || ||
Residual 85 2,521 30 || || ||
Total 88 2,974 || ||
Coefficients Standard Error T-Stat P-Value || || || ||
Intercept 14.96 3.08 4.86 0 || || || ||
X1 .04 .34 .12 .9066
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X2 .87 .29 3 .0035
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X3 .46 .22 2.09 .0400
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When testing whether the explanatory variables are jointly significant at the 5% significance
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level, the conclusion is to ________. - ✔✔reject H0, and conclude that the explanatory
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variables are jointly significant || || ||
The accompanying table shows the regression results when estimating y = β0 + β1x1 + β2x2
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+ β3x3 + ε.
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Df ss ms f significance f
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Regression 3 453 151 5.03 .0030 || || || || ||
Residual 85 2,521 30 || || ||