MATH 534 Week 6 Homework Problems

MATH 534 Week 6 Homework

1. Question: Which of the following is not an assumption of the regression model?
2. Question: Suppose for a … data set the regression equation is: y = 54.78 + 1.45x, and the point (0.00, 24.78) is in the data set. The residual for this point is _________.
3. Question: If the standard error of the estimate for a regression model … to a large number of … observations is 1.75, approximately 68% of the residuals would lie within________.
4. Question: For a regression model y = 30 − 2x, the coefficient of determination was … as equal to 0.81. The coefficient of correlation is ________.
5. Question: To test if the slope coefficient β1 in the population regression model is significantly different from zero, a hypothesis test is … on the slope coefficient b1 in the regression equation … using sample data. This test is a _____________.
6. Question: The proportion of variability of the dependent variable … for or explained by the independent variable is … the ____________.
7. Question: In the regression equation, y = 2.164 + 1.3657x, n = 6, the mean of x is 8.667, SSxx= 89.333 and Se = 3.44. A 95% prediction interval for y when x = 8 is _____________.
8. Question: A manager wishes to predict the annual cost (y) of an automobile … on the number of miles (x) … The following model was … : y = 2,000 + 0.42x. If a car is driven 15,000 miles, the … cost is ___________-.
9. Question: A manager wishes to predict the annual cost (y) of an automobile … on the number of miles (x) driven. The following model was … : y = 2,000 + 0.42x. If a car is … 20,000 miles, the … cost is ___________.
10. Question: A hospital administrator … a regression line, y = 30 + 2x, to predict y = the number of full-time employees (FTE) needed using x = the number of beds. The slope of this regression line suggests this: ______________.
11. Question: The following regression model was … to sample data with 12 observations: y= 30 + 4.50x. What is the change in the predicted value of y for a unit change in the value?
12. Question: If the relationship between y and x is … by the equation y = 1.57 + 0.0407 x, the slope coefficient 0.0407 means this: ___________.
13. Question: In the equation y = m x + b, which represents a straight lime, m is the __________.
14. Question: A quality manager is developing a regression model to predict the total number of defects as a function of the day of week the item is … Production runs are done 10 hours a day, 7 days a week. The explanatory variable is _________.
15. Question: Given a set of paired data, {X, Y}, if Y is independent of X, you would expect that the correlation coefficient is _________.
16. Question: Determine the Pearson product-moment correlation coefficient for the following data.
17. Question: A numerical measure that indicates the strength of relationship between … observations of two variables is -____________.