Refer to Exercise 6.

(a) Interpret the value of SEb in context.

(b) Find the critical value for a 99% confidence interval for the slope of the true regression line. Then calculate the confidence interval. Show your work.

(c) Interpret the interval from part (b) in context.

(d) Explain the meaning of “99% confident” in context .

Short Answer

Expert verified

(a)SEb=0.0024

(b) The confidence interval is (0.0108192,0.0251088)

(c) we have a 99percent confidence level that the true slope of the population regression line is between (0.0108192,0.0251088)

(d) "99percent confident" means that the confidence interval will contain the true value of the population parameter in 99percent of all possible samples.

Step by step solution

01

Part (a)Step 1: Given information

Given in the question that, We need to interpret the value of SEbin context.

02

Part(a) Step 2: Explanation

The researchers wanted to know how well the amount of beers a person drinks predicts his or her blood alcohol level. Sixteen individuals with a BAC of zero were given a random number of beer cans to drink. On the data, a least squares regression line was used. The question includes a residual plot and a residual histogram. For this data, the computer output is provided. The standard deviation of the slope is given in the row with "Perch" and the column with "Stdev.": SEb

SEb=0.0024

This suggests that the sample regression line's slope should differ by roughly 0.0024from the population regression line's true slope.

03

Part(b) Step 1: Given information

Given in the question that, We need to find the critical value for a 99% confidence interval for the slope of the true regression line. And calculate the confidence interval.

04

Part (b) Step 2: Explanation

The researchers wanted to know how well the amount of beers a person drinks predicts his or her blood alcohol level. Sixteen individuals with a BAC of zero were given a random number of beer cans to drink. On the data, a least squares regression line was used. The question includes a residual plot and a residual histogram. For this data, the computer output is provided. As a result, it is stated,

n=16

b=0.017964

SEb=0.0024

The sample size was reduced by two degrees of freedom:

df=n-2

=16-2

=14

In table B, the essential t--value can be discovered in the row of df=14and the column of c=99percent as follows:

t*=2.977

As a result, the confidence interval is as follows:

b-t*×SEb

=0.017964-2.977×0.0024

=0.0108192

b+t*×SEb

=0.017964+2.977×0.0024

=0.0251088

05

Part(c) Step 1: Given information

Given in the question that, We need to interpret the interval from part (b) in context.

06

Part(c) Step 2: Explanation

The researchers wanted to know how well the amount of beers a person drinks predicts his or her blood alcohol level. Sixteen individuals with a BAC of zero were given a random number of beer cans to drink. On the data, a least squares regression line was used. The question includes a residual plot and a residual histogram. For this data, the computer output is provided. As a result, portion (b)

we have, (0.0108192,0.0251088)

As a result, we have a 99percent confidence level that the true slope of the population regression line is between (0.0108192,0.0251088).

07

Part(d) Step 1: Given information

Given in the question that, We need to explain the meaning of “99% confident” in context.

08

Part(d) Step 2: Explanation

The researchers wanted to know how well the amount of beers a person drinks predicts his or her blood alcohol level. Sixteen individuals with a BAC of zero were given a random number of beer cans to drink. On the data, a least squares regression line was used. The question includes a residual plot and a residual histogram. For this data, the computer output is provided. In this case, "99percent confident" means that the confidence interval will contain the true value of the population parameter in99percent of all possible samples.

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