Question 1

The following 10 observations of variables x and y were collected.  Find the least squares regression line, and the estimated value of y when x = 3.

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The answer of The following 10 observations of variables x...

Question 2

Consider the following data values of variables x and y .  
 
 a. Determine the least squares regression line. 
 b. Find the predicted value of y for x = 9. 
 c. What does the value of the slope of the regression line tell you?

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The answer of Consider the following data values of variables...

Question 3

If the regression line is horizontal, then we conclude that y ____________________ (is\is not)related to x .

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Question 4

A prediction interval for a particular y is always ____________________ than a confidence interval for the mean of y .

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The answer of A prediction interval for a particular y...

Question 5

If the standard error of estimate is ____________________, this implies that the model's fit is poor.

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The answer of If the standard error of estimate is...

Question 6

Truck Speed vs Gas Mileage An economist wanted to analyze the relationship between the speed of a car ( x )and its gas mileage ( y ). As an experiment a car is operated at several different speeds and for each speed the gas mileage is measured. These data are shown below.  {Truck Speed vs Gas Mileage Narrative} Estimate the gas mileage of a car traveling 70 mph.

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Question 7

The degrees of freedom for the test statistic for the slope is ____________________.

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The answer of The degrees of freedom for the test...

Question 8

There is ____________________ error in estimating a mean than in predicting an individual value.

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Question 9

The unbiased estimator of the variance of the error variable is found by taking ____________________ divided by n - 2.

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The answer of The unbiased estimator of the variance of...

Question 10

For a regression analysis to be valid, the value of the error variable associated with any particular value of y is ____________________ of the value of the error variable associated with any other value of y .

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The answer of For a regression analysis to be valid,...

Question 11

Graphically, a confidence interval for the mean of y is represented as two ____________________ lines.

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The answer of Graphically, a confidence interval for the mean...

Question 12

The coefficient of ____________________ measures the amount of variation in the dependent variable that is explained by the variation in the independent variable.

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The answer of The coefficient of ____________________ measures the amount...

Question 13

If the regression line is horizontal, the slope is ____________________ and x and y are not related.

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The answer of If the regression line is horizontal, the...

Question 14

You use a(n)____________________ interval whenever you want to estimate a one-time occurrence for a particular value of y when x is a given value.

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The answer of You use a(n)____________________ interval whenever you want...

Question 15

A scatter diagram includes the following data points:  Two regression models are proposed: (1)  , and (2)  . Using the least squares method, which of these regression models provides the better fit to the data? Why?

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The answer of A scatter diagram includes the following data...

Question 16

The farther a given value of x is from the mean of x , the ____________________ the estimated error becomes.

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The answer of The farther a given value of x...

Question 17

Graphically, a prediction interval is represented as two ____________________ lines.

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The answer of Graphically, a prediction interval is represented as...

Question 18

If you take a particular x value and plug it into a regression line equation, the result is a(n)____________________ estimate for y .

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The answer of If you take a particular x value...

Question 19

You use a(n)____________________ interval whenever you want to estimate the mean of y when x is a given value.

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