You generate a scatter plot using Excel. You then have Excel plot the trend line and report the equation and the R squared value. The regression equation is reported as

Question

y=18.75x+12.43

and the R^{2= 0.5041}

What is the correlation coefficient for this data set?

Answer 1

The Correlation Coefficient is "R", You are given R², so just take the square root. HOWEVER, you must look at the slope of the regression line. A positive slope will mean that the "R" is positive, while a negative slope will mean the "R" is negative. (Going from "R" to "R²" you loose the negative sign if there is one). In this case, the slope is positive so the R is positive.

√0.5041 = 0.71 to the correlation coefficient is +0.71

Answer 2

Hey! Here is a quick solution for your question. I hope this helps. If you have any additional questions, please let me know!

-Dr. C