Question

The following table compares the completion percentage and interception percentage of 5 NFL quarterbacks.

Completion Percentage 60 61 62 62 65 Interception Percentage 4.4 2.6 2.5 2.1 1.3

Step 4 of 5: Construct the 98% confidence interval for the slope. Round your answers to three decimal places.

Step 5 of 5: Construct the 95% confidence interval for the slope. Round your answers to three decimal places. Please help

Answer 1

Completion Percentage is independent variable and Interception Percentage is dependent variable

Excel > Data > Data Analysis > Regression

SUMMARY OUTPUT
Regression Statistics
Multiple R	0.880029563
R Square	0.774452032
Adjusted R Square	0.699269376
Standard Error	0.624537924
Observations	5
ANOVA
	df	SS	MS	F	Significance F
Regression	1	4.017857143	4.017857143	10.30094006	0.048974652
Residual	3	1.170142857	0.390047619
Total	4	5.188
	Coefficients	Standard Error	t Stat	P-value	Lower 95%	Upper 95%	Lower 98.0%	Upper 98.0%
Intercept	35.79428571	10.3524848	3.457555013	0.040712407	2.848058718	68.74051271	-11.2132716	82.80184303
X	-0.535714286	0.166914781	-3.209507759	0.048974652	-1.066911615	-0.004516957	-1.29362471	0.222196139

Y = 35.7943-0.5357*X

a)

the 98% confidence interval for the slope = (-1.294, 0.222)

b)

the 95% confidence interval for the slope = (-1.067, -0.005)

(CI formula

CI = b1 +/- tc*Sb1

df = 3

tc = 4.5407(alpha = 0.02)

tc = 3.1824(alpha = 0.05))