Question

The data in the table is the number of absences for 7 students and their corresponding grade. Number of Absences 2 3 3 5 5 6 6 Grade 3.8 3.6 3.2 2.5 2.1 2 1.7 Table

Step 1 of 5 : Calculate the sum of squared errors (SSE). Use the values b0=4.8669 and b1=−0.5056 for the calculations. Round your answer to three decimal places.

Step 2 of 5 : Calculate the estimated variance of errors, s2e. Round your answer to three decimal places.

Step 3 of 5 : Calculate the estimated variance of slope, s2b1. Round your answer to three decimal places.

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 80% confidence interval for the slope. Round your answers to three decimal places.

Answer 1

SSE =Syy-(Sxy)2/Sxx=

0.217

Step 2 of 5 :

s2 =SSE/(n-2)=

0.043

Step 3 of 5 :

estimated variance of slope Var(β1) =s2/Sxx=

0.003

Step 4 of 5

for 98 % CI value of t=		3.3650
margin of error E=t*std error                            =	0.1783
lower bound=estimated slope-margin of error =	-0.684
Upper bound=estimated slope+margin of error=	-0.327

step 5:

for 80 % CI value of t=		1.4760
margin of error E=t*std error                            =	0.0782
lower bound=estimated slope-margin of error =	-0.584
Upper bound=estimated slope+margin of error=	-0.427