document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=214182>Question 214182</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I'd have a, maybe somewhat weird, question; I have to draw a scatter plot (which I did), now it says to; \"describe the nature of the correlation\"...<BR>\n" );
document.write( "I have started but didnt come far;<BR>\n" );
document.write( "r=Mxy-MX*My over &#963;x*&#963;y= 88.004-(28)(3.143) over .... I dont know what to set in for &#963;x*&#963;y and I dont understand how the problem is then solved.<BR>\n" );
document.write( "Could someone help me out with this please?<BR>\n" );
document.write( "values of x; 0, 2, 3, 4, 5, 6, 8  values of y; 1, 2, 2, 4, 3, 4, 6<BR>\n" );
document.write( "&#963; = sigma <BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #162222 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=162222\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I have to draw a scatter plot (which I did), now it says to; \"describe the nature of the correlation\"...<BR>\n" );
document.write( "I have started but didnt come far;<BR>\n" );
document.write( "r=Mxy-MX*My over &#963;x*&#963;y= 88.004-(28)(3.143) over .... I dont know what to set in for &#963;x*&#963;y and I dont understand how the problem is then solved.<BR>\n" );
document.write( "Could someone help me out with this please?<BR>\n" );
document.write( "values of x; 0, 2, 3, 4, 5, 6, 8 values of y; 1, 2, 2, 4, 3, 4, 6<BR>\n" );
document.write( "&#963; = sigma <BR>\n" );
document.write( "-------------------------<BR>\n" );
document.write( "sigma x is the standard deviation of that set of x's: it is 2.4495..<BR>\n" );
document.write( "sigma y is the standard deviation of that set of y's: it is 1.5518..<BR>\n" );
document.write( "----------------------<BR>\n" );
document.write( "When I run a Linear Regression function against the set of your<BR>\n" );
document.write( "x/y pairs I get r = 0.93956... which shows that there is a high<BR>\n" );
document.write( "level of positive linear correlation.<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "But you numbers[ 88.004-28*3.143] give a result of zero<BR>\n" );
document.write( "Then dividing by (sigma x)(sigma y) you would still get <BR>\n" );
document.write( "r = 0 which indicates there is not linear correlation.<BR>\n" );
document.write( "Something is wrong with your \"r\" calculation.<BR>\n" );
document.write( "========================================================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );