SCMT FINAL EXAM

Calculate the Correlation Coefficient from the partial Excel output given. SS(Regression)= 15.779 SS(Residual)= 8.888 SS(Total)= 24.667 X Coefficient= -0.1343 a. 0.00 b. -0.80 c. -0.64 d. 0.80 e. 0.64

-0.80

Calculate the Coefficient of Determination from the partial Excel output given. SS(regression) = 15.779 SS(residual) = 8.888 SS(total) = 24.667 1. 0.00 2. 0.80 3. 0.40 4. 0.89 5. 0.64

0.64

Predict the value of y if x=100 using the partial excel output given. Coefficient Intercept= 40.9262 Coefficient X= -0.1343 1. 37.99 2. 40.79 3. 29.89 4. 32.26 5. 27.50

27.50

Calculate the coefficient of determination for the following Data Set. X Y 1 2300 2 2400 3 2300 4 2500 a. 67.42% b. -45.45% c. -67.42% d. 45.45%

45.45%

In a simple linear regression problem, r and b1 1. Must have same sign 2. must have opposite signs. 3. are equal. 4. May have opposite signs

Must have same sign

To find the correlation coefficient between 2 variables, it does not matter which variable we term as Y because it does not make a difference to r; either variable can be X or Y. True False

True

The strength of the linear relationship between two numerical variables may be measured by the 1. Y-intercept. 2. slope. 3. scatter diagram. 4. coefficient of correlation.

coefficient of correlation.

The b0 value in the prediction equation represents a. predicted value of Y when X = 0. b. the estimated average change in Y per unit change in X. c. the predicted value of Y. d. variation around the line of regression.

predicted value of Y when X = 0

All but one of the following situations are impossible. Which is the only possible one? a. R-Square = 1.27 b. estimated slope = 1.27 while the correlation coefficient = -.27 for the same data. c. the predicted value of y decreases as x increases. d. a correlation coefficient = -1.27 e. correlation coefficient = 1.27

the predicted value of y decreases as x increases.

In regression we must select the Y variable as the variable ................ 1. used to predict the other variable. 2. with the smaller variance. 3. it does not make a difference; either variable can be X or Y. 4. which is the independent variable. 5. to be predicted.

to be predicted