STATS Ch 14

A regression analysis between sales (in $1000s) and price (in dollars) resulted in the following equation: ŷ = 50,000 − 8x The above equation implies that an increase of _____.

$1 in price is associated with a decrease of $8,000 in sales

Regression analysis was applied between sales data (in $1000s) and advertising data (in $100s), and the following information was obtained. ŷ = 12 + 1.8x n = 17 SSR = 225 SSE = 75 S b 1 = 0.2683 Refer to Exhibit 14-3. Based on the above estimated regression equation, if advertising is $3,000, then the point estimate for sales (in dollars) is _____.

$66,000

Regression analysis was applied between sales (in $1000s) and advertising (in $100s), and the following regression function was obtained. ŷ = 80 + 6.2x Based on the above estimated regression line, if advertising is $10,000, then the point estimate for sales (in dollars) is _____.

$700,000

Regression analysis was applied between sales (in $1000s) and advertising (in $100s), and the following regression function was obtained. ŷ = 500 + 4x Based on the above estimated regression line, if advertising is $10,000, then the point estimate for sales (in dollars) is _____.

$900,000

You are given the following information about x and y. x y independent dependent variable variable 4 12 6 3 2 7 4 6 Refer to Exhibit 14-6. The sample correlation coefficient equals _____.

-.4364

A regression analysis resulted in the following information regarding a dependent variable (y) and an independent variable (x). n = 10 Σx = 55 Σy = 55 Σx2 = 385 Σy2 = 385 Σxy = 220 Refer to Exhibit 14-1. The sample correlation coefficient equals _____.

-1

You are given the following information about x and y. x y independent dependent variable variable 1 5 2 4 3 3 4 2 5 1 Refer to Exhibit 14-5. The least squares estimate of b1 (slope) equals _____.

-1

In a regression analysis, if SSE = 200 and SSR = 300, then the coefficient of determination is _____.

.600

The following information regarding a dependent variable (y) and an independent variable (x) is provided. x y independent dependent variable variable 2 4 1 3 4 4 3 6 5 8 SSE = 6 SST = 16 Refer to Exhibit 14-4. The coefficient of determination is _____.

.625

You are given the following information about x and y. x y independent dependent variable variable 15 5 12 7 10 9 7 11 Refer to Exhibit 14-2. The coefficient of determination equals _____.

.9941

You are given the following information about x and y. x y independent dependent variable variable 4 12 6 3 2 7 4 6 Refer to Exhibit 14-6. The least squares estimate of b0 equals _____.

11

The following information regarding a dependent variable (y) and an independent variable (x) is provided. x y independent dependent variable variable 2 4 1 3 4 4 3 6 5 8 SSE = 6 SST = 16 Refer to Exhibit 14-4. The least squares estimate of the y-intercept is ______.

2

The following information regarding a dependent variable (y) and an independent variable (x) is provided. x y independent dependent variable variable 2 4 1 3 4 4 3 6 5 8 SSE = 6 SST = 16 Refer to Exhibit 14-4. The MSE is _____.

2

Regression analysis was applied between sales data (in $1000s) and advertising data (in $100s), and the following information was obtained. ŷ = 12 + 1.8x n = 17 SSR = 225 SSE = 75 Sb1 = 0.2683 Refer to Exhibit 14-3. The critical F value at α = .05 is _____.

4.54

Regression analysis was applied between sales data (in $1000s) and advertising data (in $100s), and the following information was obtained. ŷ = 12 + 1.8x n = 17 SSR = 225 SSE = 75 Sb1 = 0.2683 Refer to Exhibit 14-3. The F statistic computed from the above data is _____.

45

In a regression analysis, if r2 = 1, then _____.

SSE must be equal to 0

Which of the following is correct?

SST = SSR + SSE

In simple linear regression analysis, which of the following is NOT true?

The F test and the t test may or may not yield the same results.

In regression analysis, if the dependent variable is measured in dollars, the independent variable _____.

can be any units

The interval estimate of the mean value of y for a given value of x is the _____.

confidence interval

In a regression analysis, the variable that is used to predict the dependent variable ______.

is the independent variable

Larger values of r2 imply that the observations are more closely grouped about the _____.

least squares line

A least squares regression line ______.

may be used to predict a value of y if the corresponding x value is given

Application of the least squares method results in values of the y-intercept and the slope that minimizes the sum of the squared deviations between the _____.

observed values of the dependent variable and the predicted values of the dependent variable

The equation that describes how the dependent variable (y) is related to the independent variable (x) is called _____.

the regression model

In a simple regression analysis (where y is a dependent and x an independent variable), if the slope is positive, then it must be true that _____.

there is a positive correlation between x and y

If two variables, x and y, have a strong linear relationship, then _____.

there may or may not be any causal relationship between x and y

As the goodness of fit for the estimated regression equation increases, the _____.

value of the coefficient of determination increases

If there is a very strong negative correlation between two variables, then the correlation coefficient must be _____.

very close to -1

In regression analysis, the independent variable is typically plotted on the _____.

x-axis of a scatter diagram