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Is there a relationship between a student鈥檚 GPA and the number of pencils in his or her backpack? Jordynn and Angie decided to find out by selecting a random sample of students from their high school. Here is computer output from a least squares regression analysis usingx=numberpencils and y=GPA:

PredictorCoefSECoefTPConstant3.24130.180917.9200.0000Pencils0.04230.06310.6700.5062S=0.738533R-Sq=0.9%R-Sq(adj)=0.0%

Is there convincing evidence of a linear relationship between GPA and the number of pencils for students at this high school? Assume the conditions for inference are met.

Short Answer

Expert verified

No, the convincing evidence of a linear relationship between GPAand the number of pencils for students at this high school.

Step by step solution

01

Given Information

We need to find convincing evidence of a linear relationship between GPAand the number of pencils for students at this high school.

02

Simplify 

Consider:

n=Samplesize=Unknown=Significancelevel=0.05

The estimate of the slope b1is given in the row "Pencils" and in the column "Coef" of the given computer output:

b1=-0.0423

The estimated standard deviation of the slope SEb1is given in the row "Time" and in the column "SE Coef" of the given computer output:

SEb1=0.0631

Given claim: Slope is nonzero (reduction):

The null hypothesis or the alternative hypothesis states the given claim The null hypothesis states that the slope is zero. If the given claim is the null hypothesis, then the alternative hypothesis states the opposite of the null hypothesis:

H0:1=0H:1<0

Compute the value of the test statistic

t=b11SEb1=0.042300.06310.6704

The P-Value is given in the row "Pencils" and in the column "P" of the computer output:

P=0.5062

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Most popular questions from this chapter

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d. If there is no linear relationship between average number of putts per hole and total winnings for the players on the PGA Tour鈥檚 world money list, the probability of getting a random sample of 69 players that yields a least-squares regression line with a slope of 鈭4,139,198 or less is 0.0087.
e. The probability of making a Type I error is 0.0087.

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