document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=260293>Question 260293</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Question:\r<BR>\n" );
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document.write( "2.Construct a scatter plot and include the regression line on the graph using excel for the given data. Determine whether there is a positive linear correlation, negative linear correlation, or no linear correlation. Complete the table and find the correlation coefficient r\r<BR>\n" );
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document.write( "In an area of the Midwest, records were kept on the relationship between the rainfall (in inches) and the yield of wheat (bushels per acre). \r<BR>\n" );
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document.write( "Rain fall, x	10.5	8.8	13.4	12.5	18.8	10.3	7.0	15.6	16.0<BR>\n" );
document.write( "Yield, y	50.5	46.2	58.8	59.0	82.4	49.2	31.9	76.0	78.8\r<BR>\n" );
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document.write( "Scatter plot with regression line  : I have already done this part\r<BR>\n" );
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document.write( "Type of correlation (positive linear correlation, negative linear correlation, or no linear correlation)  Answer: positive linear correlation\r<BR>\n" );
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document.write( "Complete the table and find the correlation coefficient r rounded to 4 decimals.<BR>\n" );
document.write( "n=9<BR>\n" );
document.write( "r= 9(7187.77)-(112.9)(532.8)/square root 9 (1521.39)-112.92 square root 9 (33,836.58)-532.8*532.8=453.6/square root 9.46 square root 2.06=\r<BR>\n" );
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document.write( "Using the r calculated in problem 2c  test the significance of the correlation coefficient using &#61537; = 0.01 and the claim rho = 0. Use the 7-steps hypothesis test shown at the end of this project. (Note: Round the computed t to 3 decimals.)<BR>\n" );
document.write( "1.  H0 :  <BR>\n" );
document.write( "Ha : <BR>\n" );
document.write( "2.  &#61537; this symbol means Specify the level of significance alpha  = <BR>\n" );
document.write( "3.  Find the test statistic :t= r/square root 1-r^2/n-2<BR>\n" );
document.write( "4.  the critical value(s) t0.  <BR>\n" );
document.write( "5.  Rejection region: <BR>\n" );
document.write( "6.  Decision: <BR>\n" );
document.write( "7.  Interpretation: \r<BR>\n" );
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document.write( "Find the test statistic :t= r/square root 1-r^2/n-2 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #191778 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=191778\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 2.Construct a scatter plot and include the regression line on the graph using excel for the given data. Determine whether there is a positive linear correlation, negative linear correlation, or no linear correlation. Complete the table and find the correlation coefficient r <BR>\n" );
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document.write( "In an area of the Midwest, records were kept on the relationship between the rainfall (in inches) and the yield of wheat (bushels per acre). <BR>\n" );
document.write( "Rain fall, x 10.5 8.8 13.4 12.5 18.8 10.3 7.0 15.6 16.0<BR>\n" );
document.write( "Yield, y 50.5 46.2 58.8 59.0 82.4 49.2 31.9 76.0 78.8 <BR>\n" );
document.write( "Scatter plot with regression line : I have already done this part <BR>\n" );
document.write( "Type of correlation (positive linear correlation, negative linear correlation, or no linear correlation)<BR>\n" );
document.write( "Answer: positive linear correlation <BR>\n" );
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document.write( "Complete the table and find the correlation coefficient r rounded to 4 decimals.<BR>\n" );
document.write( "n=9<BR>\n" );
document.write( "r= 9(7187.77)-(112.9)(532.8)/square root 9 (1521.39)-112.92 square root 9 (33,836.58)-532.8*532.8=453.6/square root 9.46 square root 2.06=<BR>\n" );
document.write( "Note: I get r = 0.962 using a TI calculator.<BR>\n" );
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document.write( "Using the r calculated in problem 2c test the significance of the correlation coefficient using alpha = 0.01 and the claim rho = 0. Use the 7-steps hypothesis test shown at the end of this project. (Note: Round the computed t to 3 decimals.)<BR>\n" );
document.write( "1. <BR>\n" );
document.write( "H0 :pho = 0 (that means no linear correlation) <BR>\n" );
document.write( "Ha :pho is not 0<BR>\n" );
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document.write( "2. &#61537; this symbol means Specify the level of significance alpha = 1%<BR>\n" );
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document.write( "3. Find the test statistic :t= r/square root 1-r^2/n-2<BR>\n" );
document.write( "t = (1-0.962^2)/(9-2) = 0.01065<BR>\n" );
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document.write( "4. the critical value(s) t0 = invT(0,005,8) = +/-3.3554<BR>\n" );
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document.write( "5. Rejection region:<BR>\n" );
document.write( "Reject Ho if |t|> 3.3554<BR>\n" );
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document.write( "6. Decision:<BR>\n" );
document.write( "The test Stat is not in the rejection interval so fail to reject Ho<BR>\n" );
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document.write( "7. Interpretation: Reject the claim that there is no linear correlation.<BR>\n" );
document.write( "The test supports the claim there is linear correlation at the 1% significance<BR>\n" );
document.write( "level.<BR>\n" );
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document.write( "Find the test statistic :t= r/square root 1-r^2/n-2<BR>\n" );
document.write( "Comment: Whic formula are you using? this or the one above?<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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