Testing the null hypothesis that the slope of the true regression ...

[dollx]

Testing the null hypothesis that the slope of the true regression line equals zero is equivalent to testing whether the true coefficient of correlation could be zero. Why?

Question 2

The values of y and x are inversely related, and 84.64 of the variation in y is explained by the regression equation. What is the coefficient of correlation?

[yuyiding]

Answer to Question 1

If the slope of the true regression line is zero, then the true coefficient of correlation is also zero. Both of these cases imply no linear relationship between the dependent variable (y) and the independent variable (x).

Answer to Question 2

Since 84.64 of the variation in y is explained by x .8464 is the coefficient of determination. The square root of the coefficient of determination, with the appropriate sign, is equal to the coefficient of correlation. Therefore, the coefficient of correlation is -.92 . We know this is negative because y and x are inversely related.

[dollx]

TYSM

[komodo7]

Thanks for the timely response, appreciate it