Question

Given here are data for a dependent variable and four potential predictors.

y	x1	x2	x3	x4	x5
96	8	60	2.4	48	51
73	6	64	2.1	42	43
108	2	76	1.8	34	20
124	5	74	2.2	11	14
82	6	50	1.5	61	29
89	9	57	1.6	53	22
76	1	72	2	72	38
109	3	74	2.8	36	40
123	2	99	2.6	17	50
125	6	81	2.5	48	55
101	2	77	1.2	42	57
127	4	72	1.7	26	34
98	9	69	2.4	47	21
79	5	53	2.6	65	25
118	3	88	2.9	37	43
114	1	53	2.7	28	40
110	3	82	2.8	29	52
94	2	61	2.6	22	38
102	4	80	2.5	12	15
97	10	68	3	45	20

1. Use these data and a stepwise regression procedure to develop a multiple regression model to predict y; examine the values of t and R² at each step and comment on those values. How many steps did the procedure use? Why do you think the process stopped?

2. Determine whether there may be a problem with multicollinearity. Construct a correlation matrix of the five variables to aid you in this task.

Answer 1