2.)What information is provided by the numerical value of the Pearson Correlation?

4.) Calculate SP ( the sum of products of deviations) for the following scores. Note: Both means are whole numbers, so the definition formula works well

____________

X Y

____________

0 2

1 4

4 5

3 3

7 6

6.) For part a, either create the sketch using Word or submit a jpeg as separate file.

8.) For part a, either create the sketch using Word or submit a jpeg as separate file.

Additional Item:

1.) Discuss the relationship between correlation and cause and effect (causality). Use examples (maximum 250 words).

2.) When is it appropriated to use the Spearman correlation rather than the Pearson correlation? Use examples (maximum 250 words).

2.) The regression equation is intended to be the best fitting straight line for a set of data. What is the criterion for the best fitting?

4.) A set of n= 25 pairs of scores ( X and Y values) produces a regression equation of =3X-2. Find the predicted Y value for each of the following X scores: 0,1,3,-2

6.) In general, how is the magnitude of the standard error of estimate related to the value of correlation?

8.) For the following data:

A. Find the regression equation for predicting Y from X

B. Calculate the Pearson correlation for these data. Use r and SS y to compute SS residual

and the standard error of estimate for the equation

12.) A professor obtains SAT scores and freshmans grade point average (GPAs) for a group of

college students. The SAT scores have a mean of M= 580 with SS=22,400, and the

GPAs have a mean of 3.10 with SS = 1.26, and SP .

A. Find the regression equation for predicting GPA from SAT scores

B. What percentage of the variance in GPAs is accounted for by the regression equation? (compute the correlation, r, then find r ).

C. Does the regression equation account for a significant portion of the variance in GPA? Use = .05 to evaluate the F- ratio.