Question

Assuming the residuals are normally​ distributed, construct a​ 90% confidence interval for the slope of the true​ least-squares regression line.

Lower​ bound: ?

​(Round to four decimal places as​ needed.)

Upper​ bound:?

​(Round to four decimal places as​ needed.)

​(d) What is the mean rate of return for the company stock if the rate of return of the index is

3.15%?

The mean rate of return for the company stock if the rate of return of the index is 3.15​% is _____%.

Month	Rates_of_return_of_the_index_-_x	Rates_of_return_of_the_company_stock_-_y
Apr-07	4.33	3.28
May-07	3.25	5.09
Jun-07	-1.78	0.54
Jul-07	-3.2	2.88
Aug-07	1.29	2.69
Sept-07	3.58	7.41
Oct-07	1.48	-4.83
Nov-07	-4.4	-2.38
Dec-07	-0.86	2.37
Jan-08	-6.12	-4.27
Feb-08	-3.48	-3.77

Answer 1

SUMMARY OUTPUT
Regression Statistics
Multiple R	0.661585916
R Square	0.437695925
Adjusted R Square	0.375217694
Standard Error	3.230852226
Observations	11
ANOVA
	df	SS	MS	F	Significance F
Regression	1	73.12703597	73.12703597	7.005574916	0.026615234
Residual	9	93.94565494	10.4384061
Total	10	167.0726909
	Coefficients	Standard Error	t Stat	P-value	Lower 95%	Upper 95%	Lower 90.0%	Upper 90.0%
Intercept	1.228592627	0.986348263	1.245597191	0.244362927	-1.00268216	3.459867411	-0.579495121	3.036680374
Rates_of_return_of_the_index_-_x	0.762185938	0.287964559	2.646804661	0.026615234	0.110764849	1.413607027	0.234314383	1.290057493

Rates_of_return_of_the_company_stock_-_y = 1.2286 + 0.7622 * Rates_of_return_of_the_index_-_x

90% confidence interval for slope :

Lower​ bound : 0.234314383 = 0.2343

Upper​ bound : 1.290057493 = 1.2901

the mean rate of return for the company stock if the rate of return of the index is 3.15%

Rates_of_return_of_the_company_stock_-_y = 1.2286 + 0.7622 * 3.15

= 3.6295

The mean rate of return for the company stock if the rate of return of the index is 3.15​% is 3.6295%.