Question

Regression (with provided table)

	x	y	x-xmean	(x-xmean)2	y-ymean	(y-ymean)2	(x-xmean) (y-ymean)
	4	80	-0.33	0.11	1	1	-0.33
	7	92	2.67	7.11	13	169	34.67
	1	52	-3.33	11.11	-27	729	90.00
	5	76	0.67	0.44	-3	9	-2.00
	8	106	3.67	13.44	27	729	99.00
	5	100	0.67	0.44	21	441	14.00
	2	69	-2.33	5.44	-10	100	23.33
	4	71	-0.33	0.11	-8	64	2.67
	3	65	-1.33	1.78	-14	196	18.67
SUM	39	711		40		2438	280
Mean	4.333333	79
Std. Dev.	2.24	17.46
n	9	9

Regression Directions:

Using the above table, work out the following:

1. Calculate r
2. Calculate b
3. Calculate a
4. Write the regression equation in y = a +bx format
5. Predict y where x = 5 (Question 4) and x=15 (Question5)

Answer 1

from above

a)

r =0.8966

b)

b =7

c)a =48.6667

d) regression equation: Y =48.6667+7x

e) predicted value =48.6667+7*15 =153.6667