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Chapter 12: Q. T12.3 (page 824)

T12.3 Inference about the slope 尾1 of a least-squares regression line is based on which of
the following distributions?
a. The tdistribution with n鈭�1 degrees of freedom
b. The standard Normal distribution
c. The chi-square distribution with n鈭�1 degrees of freedom
d. The t distribution with n-2 degrees of freedom
e. The Normal distribution with mean 渭 and standard deviation 蟽.

Short Answer

Expert verified

The correct answer is option (d) The tdistribution with n-2 degrees of freedom.

Step by step solution

01

Given information

To inference about the slope 尾1 of a least-squares regression line is based on which of the following distributions.

02

Explanation

To figure out the below distributions biases inference about a least-squares regression line's slope 尾1.
To establish the least square regression line, two parameters must be estimated: the y-intercept and the slope.
The t-distribution with degrees of freedom equal to the sample size n minus the number of calculated parameters becomes the appropriate distribution.
As a result,
df=n-2
Therefore, the correct answer is option (d).

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Most popular questions from this chapter

Exercises T12.4鈥揟12.8 refer to the following setting. An old saying in golf is 鈥淵ou drive for show and you putt for dough.鈥� The point is that good putting is more important than long driving for shooting low scores and hence winning money. To see if this is the case, data from a random sample of 69 of the nearly 1000 players on the PGA Tour鈥檚 world money list are examined. The average number of putts per hole (fewer is better) and the player鈥檚 total winnings for the previous season are recorded and a least-squares regression line was fitted to the data. Assume the conditions for
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