Assuming that these are both continuous variables, it means that the slope of the relationship between X1 and Y is greater than the relationship between X2 and Y. X1 has 1 over it and X2 has a -1 over it. You can only tell +/- correlation if you have a 1 or -1 over a single column OR if you want the average slope you can have 1s or -1s over several columns, but you can have both. As soon as you have both, then you are testing the difference in the slopes.<div>
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<br><br><div class="gmail_quote">On Fri, Jan 29, 2010 at 3:03 AM, Kelly Atalaia Silva <span dir="ltr">&lt;<a href="mailto:[log in to unmask]"><a href="/cgi-bin/wa-jisc.exe?LOGON=A3%3Dind1001%26L%3DSPM%26E%3Dquoted-printable%26P%3D3895333%26B%3D--000e0cd17c982cf8bf047e4f0f28%26T%3Dtext%252Fhtml%3B%2520charset%3DISO-8859-1%26pending%3D" target="_parent" >[log in to unmask]</a></a>&gt;</span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
Hello,<br>  I would like to know how can I know the direccion of one correlation in SPM. For example, if I put &quot;1&quot; on one variable of interest and &quot;-1&quot; into another variable does it means that there is a negative correlation between both variables?<br>

                                  Thanks in advance,<br><font color="#888888">                                            Kelly<br>
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