Calculate the linear correlation coefficient r.

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X Y - X Y
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310 3.2 - 250 2.5
280 3.0 - 360 3.4
120 2.6 - 215 2.6
230 3.5 - 365 3.8
175 2.8 - 230 3.0
295 3.8 - 325 3.8
135 2.2 - 280

Question

Calculate the linear correlation coefficient r.

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X                    Y         -            X                Y
______________________________________________
310                3.2     -           250           2.5
280                3.0     -          360            3.4
120                2.6    -           215            2.6
230                3.5   -            365            3.8
175                2.8   -            230            3.0
295                3.8   -            325            3.8
135                2.2   -            280

anonymous · Answer

(last part is 3.3)

zarkon · Answer

just us the formula... http://en.wikipedia.org/wiki/Pearson_product-moment_correlation_coefficient#For_a_sample

directrix · Answer

@Usuii There is an interesting linear coefficient of correlation online calculator you may want to investigate. I was interested in it and ran your numbers. I cannot vouch for the correctness of the "calculator" answer. Attached is the "calculator answer." http://www.easycalculation.com/statistics/correlation.php