Description of this paper

Exam: INFERENCES AND LINEAR REGRESSION

Description

solution


Question

Question;1. In a hypothesis test for the population variance, the alternate hypothesis is the population variance does not equal 17.0. The significance level to be used is 0.05 and the sample size to be taken is 25. The table value(s) to use from the chi-square distribution is/areA. 40.647.B. 39.364.C. 12.401 and 39.364.D. 13.120 and 40.647. 2. The vertical distances between observed and predicted values of y are calledA. methods of least squares.B. errors of prediction.C. least square lines.D. scatterplots.3. In testing for the equality of two population variances, when the populations are normally distributed, the 10% level of significance has been used. To determine the rejection region, it will be necessary to refer to the F table corresponding to an upper-tail area ofA. 0.05.B. 0.10.C. 0.20.D. 0.90.4. In testing the difference between two population means using two independent samples, we use the pooled variance in estimating the standard error of the sampling distribution of the sample mean difference x?1? x?2if theA. ample sizes are both large.B. sizes are both greater than 30.C. populations are at least normally distributed with equal variances.D. populations are nonnormal with unequal variances.5. A random sample of males and females involved in rear-end accidents results in the following Minitab summary:What is the standard error of the statistic between the two means? N MEAN MEDIAN TRMEAN STDEV SEMEANFEMALES 33 23.91 20.00 23.38 9.77 1.70MALES 38 28.87 28.50 28.44 9.67 1.57A. 4.96 B. 1.635C. 0.897D. 2.3146. A balanced experiment requires thatA. an equal number of persons or test units receives each treatment.B. the number of treatments equals the number of samples.C. at least one sample equal size is 30.D. at least two treatment groups be used.7. An indication of no linear relationship between two variables would be a coefficient ofA. determination equal to 1.B. determination equal to?1.C. correlation equal to?1.D. correlation of 0.8. Lily Energy Systems manufacturer's wood-burning heaters and fireplace inserts. One of its systems has an electric blower, which is thermostatically controlled. The blower is designed to automatically turn on when the temperature in the stove reaches 125?F and turn off at 85?F. Complaints from customers indicate that the thermostat control is not working properly. The company feels that the thermostat is acceptable if the variance in the cutoff temperature is less than or equal to 175. The company takes a sample of 24 thermostats and finds that the variance equals 289. The calculated chi-square test statistic and the table value for a 0.05 significance level areA. 37.983, 38.076.B. 37.983, 35.172.C. 38.076, 38.99.D. 35.172, 38.99.9. Given the significance level 0.025, the F-value for the degrees of freedom, df = (7,3) isA. 5.89.B. 27.67.C. 8.45.D. 14.62.10. The object on which the response and factors are observed is calledA. treatments.B. experimental unit.C. factor level.D. factors.11. The F-statistic in a one-way ANOVA represents the variationA. within the treatments minus the variation between the treatments.B. between the treatments divided by the variation within the treatments.C. within the treatments divided by the variation between the treatments.D. between the treatments plus the variation within the treatments.12. In testing a population variance or constructing a confidence interval for the population variance, an essential assumption is thatA. expected frequencies equal or exceed 5.B. the population is normally distributed.C. the population is uniformly distributed.D. sample size exceeds 30.13. Which of the following statements are true regarding the simple linear regression model yi=?0+?1xi+?i?A.?0is the slope of the regression line.B.?iis a nonrandom error.C. yiis a value of the dependent variable (y) and xiis a value of the independent variable (x).D.?1is the y-intercept of the regression line.14. A left-tail area in the chi-square distribution equals 0.95. For df = 10, the table value equalsA. 15.987.B. 18.307.C. 3.940.D. 20.483.15. Another name for the residual term in a regression equation isA. homoscedasticity.B. pooled variances.C. residual analysis.D. random error.16. A random sample of males and females involved in rear-end accidents results in the following Minitab summary:N MEAN MEDIAN TRMEAN STDEV SEMEANFEMALES 33 23.91 20.00 23.38 9.77 1.70MALES 38 28.87 28.50 28.44 9.67 1.57End of exam What is the value of the test statistic (Z score)? A. 1.64B. 2.32C.?2.14D.?4.96 17. In using the ANOVA models, the assumptions made about the data areA. the samples are independent.B. all 3 assumptions made here about the data.C. the population variances are equal.D. the population distributions are normal.18. What is the slope of the line that passes through the points (?5,?8) and (3,8)?A. ?B. 2C.?2D.??19. Consider the following data values of variables x and y.Find the least squares regression line. x 4 2 6 4 3y 5 3 7 6 5A. 1.122 + 1.073xB. 1.659 + 0.932xC.?1.045 + 0.932xD. 21.206 + 1.073x20. In testing the difference between two population means using two independent samples, the sampling distribution of the sample mean difference x?1? x?2is normal if theA. population sizes are both greater than 30.B. populations are nonnormal and the sample sizes are large.C. sizes are both greater than 30.D. populations are normal.

 

Paper#61137 | Written in 18-Jul-2015

Price : $27
SiteLock