Question

6. Consider the following set of dependent and independent variables. Use this data to complete parts a and b below.

Construct a​ 95% confidence interval for the regression coefficient for x1

y   x1   x2
9   0   18
14   3   9
16   3   13
16   8   11
22   9   4
24   11   7
25   13   6
32   21   6

a. The​ 95% confidence interval for the true population coefficient B1 is _____ to _____. (Round to three decimal places as​ needed.)

b. Construct a​ 95% confidence interval for the regression coefficient for x2.

The​ 95% confidence interval for the true population coefficient β2 is ______ to _____. ​(Round to three decimal places as​needed.)

Answer 1

Applying regression from excel: with data-data analysis -regression:

	Coefficients	Standard Error	t Stat	P-value	Lower 95%	Upper 95%	Lower 95.0%	Upper 95.0%
Intercept	15.59429	3.077636	5.066971	0.003877	7.682976	23.5056	7.682976	23.5056
x1	0.87813	0.146331	6.000979	0.001845	0.501974	1.254286	0.501974	1.254286
x2	-0.35766	0.214183	-1.6699	0.155806	-0.90824	0.19291	-0.90824	0.19291

a)

95% confidence interval for the true population coefficient B1 is 0.502 to 1.254

b) 95% confidence interval for the true population coefficient β2 is is -0.908 to 0.193