document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=140333>Question 140333</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help!<BR>\n" );
document.write( "In the following regression, X = weekly pay, Y = income tax withheld, and n = 35 McDonald’s employees. (a) Write the fitted regression equation. (b) State the degrees of freedom for a two-tailed test for zero slope, and use Appendix D to find the critical value at &#945; = .05. (c) What is your conclusion about the slope? (d) Interpret the 95 percent confidence limits for the slope. (e) Verify that F = t2 for the slope. (f) In your own words, describe the fit of this regression.\r<BR>\n" );
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document.write( "Regression output confidence interval<BR>\n" );
document.write( "variables coefficients std. error t (df = 33) p-value 95% lower 95% upper<BR>\n" );
document.write( "Intercept 30.7963 6.4078 4.806 .0000 17.7595 43.8331<BR>\n" );
document.write( "Slope 0.0343 0.0119 2.889 .0068 0.0101 0.0584<BR>\n" );
document.write( "ANOVA table<BR>\n" );
document.write( "Source SS df MS F p-value<BR>\n" );
document.write( "Regression 387.6959 1 387.6959 8.35 .0068<BR>\n" );
document.write( "Residual 1,533.0614 33 46.4564<BR>\n" );
document.write( "Total 1,920.7573 34\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #102782 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=102782\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In the following regression, X = weekly pay, Y = income tax withheld, and n = 35 McDonald’s employees.<BR>\n" );
document.write( "(a) Write the fitted regression equation. <BR>\n" );
document.write( "y = 30.7963 + 0.0343X<BR>\n" );
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document.write( "(b) State the degrees of freedom for a two-tailed test for zero slope, and use Appendix D to find the critical value at &#945; = .05.<BR>\n" );
document.write( "df= 33 ; critical value = 1.692<BR>\n" );
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document.write( "(c) What is your conclusion about the slope? <BR>\n" );
document.write( "Since 2.889 is greater than 1.692, Reject Ho.  The slope is not 0.<BR>\n" );
document.write( "There is a linear relation between X and Y.<BR>\n" );
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document.write( "(d) Interpret the 95 percent confidence limits for the slope.<BR>\n" );
document.write( "We can be 95% confidence the slope is between 0.0101 and 0.0584<BR>\n" );
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document.write( "(e) Verify that F = t2 for the slope.<BR>\n" );
document.write( "8.35 = 2.889^2 <BR>\n" );
document.write( "(f) In your own words, describe the fit of this regression.<BR>\n" );
document.write( "Based on p-values both the intercept and the slope are good.<BR>\n" );
document.write( "Income tax withheld increases by 0.0343 for every increase of one<BR>\n" );
document.write( "dollar of weekly pay. <BR>\n" );
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document.write( "Regression output confidence interval<BR>\n" );
document.write( "variables coefficients std. error t (df = 33).. p-value.. 95% lower.. 95% upper<BR>\n" );
document.write( "Intercept.. 30.7963..... 6.4078... 4.806....... .0000..... 17.7595.... 43.8331<BR>\n" );
document.write( "Slope....... 0.0343..... 0.0119... 2.889....... .0068...... 0.0101..... 0.0584<BR>\n" );
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document.write( "ANOVA table<BR>\n" );
document.write( "Source....... SS... df MS........ F.. p-value<BR>\n" );
document.write( "Regression 387.6959. 1. 387.6959 8.35 .0068<BR>\n" );
document.write( "Residual 1,533.0614 33.. 46.4564<BR>\n" );
document.write( "Total... 1,920.7573 34 \r<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.\r<BR>\n" );
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