Regression Assign #8

normally we study social loafing or the idea that people often work less hard on collective (group) tasks than they do when working on individual tasks. Imagine u want to examine social loafing as it relates to group size and correctness on a math task (number of math problems accurately solved). You look at the size of the group (ranging from 1 to 6 members) and the average number of math problems each group solves (on a ratio scale ranging from 0 to 30 correct). Below are the data for a sample of n=12 participants. Using Group Size (X) and Number of Math Problems Completed Correctly (Y), fill in the blank spaces in following chart to assess this relationship.

	Group Size (X)	Math Problems Completed (Y)	X2	Y2	XY
	1	26
	1	24
	2	20
	2	23
	3	19
	3	16
	4	14
	4	13
	5	12
	5	11
	6	11
	6	10
Total

1. Which of the following is correct?

A). The predictor (independent) variable is Group Size. The criterion (dependent) variable is Math Problems. The researchers are trying to see if Math Problems solved predicts the group size

B). The predictor (independent) variable is Math Problems. The criterion (dependent) variable is Group Size. The researchers are trying to see if Math Problems solved predicts the group size

C). The predictor (independent) variable is Group Size. The criterion (dependent) variable is Math Problems. The researchers are trying to see if Group Size predicts the Math Problems solved

D). The predictor (independent) variable is Math Problems. The criterion (dependent) variable is Group Size. The researchers are trying to see if Group Size predicts the Math Problems solved

2. What is the correct regression weight (b)? (round to three decimal places here).

A). 27.23

B). 3.043

C). -1.365

D). -3.043

E). -27.23

3. What is the correct regression intercept (a)? (round to three decimal places here)

A). 27.23

B). 3.043

C). -1.365

D). -3.043

E). -27.23

4. What is the correct regression equation (Y')? (use three decimal places here)

A). Y' = 3.043X + 27.233

B). Y' = 27.233X -3.043

C). Y' = -3.043X + 27.233

D). Y' = -3.043X - 27.233

E). X = -3.043Y' + 27.233

5. Imagine a participant was placed in a 7-person group. Given your regression equation, what is the average number of math problems you would expect this participant to complete? (For your final answer, please round to two decimal places - your answer might differ by a few decimals, so choose the BEST option from those below)

A). 22.13

B). 18.44

C). 8.76

D). 5.93

E). 2.11