Question 138776
In the following regression, 
X = weekly pay, Y = income tax withheld, and n = 35 McDonald’s employees. 
(a) Write the fitted regression equation.
Income Tax = 0.0343 (weekly pay) +30.7963
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(b) State the degrees of freedom for a two tailed for zero slope, and use Appendix D to find the critical value at α = .05.
df=33 ; t = 1.96
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(c) What is your conclusion about the slope? 
Since p-value is less than 5% Reject Ho that the correlation is zero.
Accept the slope value of 0.0343
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(d) Interpret the 95 percent confidence limits for the slope.
With 95% confidence we can state that the slope is between 0.0101 and 0.0584
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(e) Verify that F = t2 for the slope.
8.35 = 2.889^2
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(f) In your own words, describe the fit of this regression.
Since R^2 is only 0.202 only 20.2% of the correlation between
the variables is explained by the regression equation.
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Cheers,
Stan H. 
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R2 0.202 Std. Error 6.816 n 35 
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ANOVA table
Source....... SS... df     MS       F    p-value
Regression 387.6959 1  387.6959 8.35 .0068
Residual 1,533.0614 33  46.4564
Total 1,   920.7573 34 
Regression output confidence interval
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variables coefficients std. error t (df = 33) p-value 95% lower 95% upper
Intercept 30.7963 ........6.4078... 4.806        .0000     17.7595 43.8331
Slope      0.0343 ........0.0119... 2.889....... .0068..... 0.0101 0.0584
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