# ECO 578 midterm exam FALL 2015

vPart A: Multiple Choice (1–16)Using the following information to answer questions 1-8: 2130120514_____1. What is the mean?a) 1. 90b) 2. 11c) 1. 73d) 1. 66_____2. What is the median?a) 1. 00b) 1. 50c) 1. 60d) 1. 90_____3. What is the mode?a) 0b) 1c) 2d) 3_____4. What is the range?a) 1b) 4c) 5d) 3_____5. What is the variance?a) 1. 66b) 2. 77c) 1. 76d) 3. 11_____6. What is the standard deviation?a) 1. 66b) 2. 77c) 1. 76d) 3. 11_____7. What is the 1st quartile?a) 0b) 1c) 2d) 3_____8. What is the 70th percentile?a) 1b) 1. 5c) 2d) 2. 5Questions 9-16 refer to the following frequency distribution: The following information represents the number of tons of grain stored at the 60 grain elevators of central Soya, Inc. ClassFrequency_____9. What is the relative frequency for the class 170-174?a) 16b) 36c) 0. 27d) 0. 60_____10. What is the mean?a) 170. 25b) 12c) 172. 75d) 167_____11. What is the median?a) 169. 5b) 170c) 172. 63d) 173. 13160-1646165-16914170-17416175-17913180-18411Total60_____12. What is the mode?a) 16b) 170c) 172d) 174_____13. What is the variance?a) 39. 68b) 12. 33c) 151. 55d) 149. 02_____14. What is the standard deviation?a) 6. 30b) 3. 51c) 12. 31d) 12. 21_____15. What is the 1st quartile?a) 168. 21b) 167. 07c) 167. 57d) 167. 71_____16. What is the 70th percentile?a) 176. 35b) 176. 85c) 176. 81d) 177. 31vPart B: True or False (17-30)_____17. The random sample is the most important, because statistical theory applies to it alone. _____18. In a frequency distribution, the class mark is the number of observations that fall within that class. _____19. Original class interval frequencies can be obtained by multiplying the respective relative frequencies by the total number of observations. _____20. The sum of the class frequencies is equal to the number of observations made. _____21. A relative frequency distribution describes the proportion of data values that fall within each category. _____22. There would be no need for statistical theory if census, rather than a sample was always used to obtain information about populations. _____23. The arithmetic mean is the sum of the data values divided by the number of observations. _____24. is_____25. The median always exists in a set of numerical data. _____26. means that A and B are mutually exclusive events. _____27. Mutually exclusive events imply that if one event occurs, the other cannot occur. An event (e. g. ,) and its complement are always mutually exclusive. _____28. _____29. Events are independent when the occurrence of one event has no effect on the probability that another will occur. _____30. The P(x) is always 0 ≤ P(x) ≤ 1. vPart C: Answer the following questions (31-39)31. Name 3 types of statistical samples12332. Name reasons why we use samples instead of an entire population33. Name types of random samples. 34. Name the measure of central tendency. 35. Name measures of spread or variability. 36. Show that you understand the difference between a sampling error and a sampling bias. 37. Name 4 parts of the regression. 38. When do we use the regression?39. Explain the concept of error and uncertainty as it relates to decision making. vPart D: Must show all your work step by step in order to receive the full credit, Excel is not allowed. (40-50)40. Train A and Train B are two transportations that people can use to transport from Boston to New York. Sample of times recorded in minutes for each train are shown below. Train A28293237332529324134Train B29313332343031323533Please answer the following questions (a-i). Train ATrain Ba) Meanb) Meanc) Mediand) Mediane) Variancef) Varianceg) Standard deviationh) Standard deviationi) From above computed results from Train A and Train B, what train should be preferred and why?41. Use the information from the problem number 5 on page 3-21 to fill in the given table below and answer the following questions (a-h) (**Using D-method). Number of miles flownNumber of frequentFlyers (f)CFMidPoint(x)dfdd2fd2(1,000)-101234Totala) Find meanb) Find medianc) Find moded) Find Rangee) Find variancef) Find standard deviationg) Find 1st Quartileh) Find 99th percentile42. Use the information from the problem number 1 on page 3-39 to fill in the given table below and answer the following questions (a-h) (**Using D-method). Dinner CheckFrequency(f)CFMidPoint(x)dfdd2fd2($)-2-10123Totala) Find meanb) Find medianc) Find moded) Find Rangee) Find variancef) Find standard deviationg) Find 3rd Quartileh) Find 80th percentile43. The mean GMAT score of 65 applicants who were accepted into the MBA program of Xavier Business School was 520 with variance of 225. About how many applicants scored between 470 and 570 on the GMAT?44. Work on problem number 11 on page 3-49 (a-b). a)b)45. Use the information from the problem number 2 on page 4-8 and answer the following questions (a-h), Given that Y = Income rate and X = Average expensea) Findb) Findc) Interpret the meaning ofd) Find the regression equatione) Predict the income rate for an area with an average expense of $75f) Compute the coefficient of determinationg) Interpret the coefficient of determinationh) Compute and interpret the coefficient of correlation46. An educator wants to see how strong the relationship is between a student’s score on a test and his or her grade-point average. The data obtained from the sample are shown. Test Score (X)9810510010010695116112GPA (Y)2. 12. 43. 22. 72. 22. 33. 83. 4a) Findb) Findc) Interpret the meaning ofd) Find the regression equatione) Predict the GPA for a student who gets 145 in the test score. f) Compute the coefficient of determinationg) Interpret the coefficient of determinationh) Compute and interpret the coefficient of correlation47. Please use the given printout and answer the following questions. SUMMARY OUTPUTRegression StatisticsMultiple R0. 190885429R Square0. 036437247Adjusted R Square-0. 44534413Standard Error2. 502630195Observations4ANOVAdfSSMSFSignificance FRegression10. 4736842110. 473684210. 07563030. 809114571Residual212. 526315796. 26315789Total313CoefficientsStandard Errort StatP-valueLower 95%Upper 95%Intercept2. 8947368421. 9042160541. 520172480. 2678372-5. 29844356111. 08792X Variable-0. 3157894741. 148285486-0. 27500950. 8091146-5. 2564631534. 624884a) What isb) What isc) Interpret the meaning ofd) What is the regression equatione) What is the coefficient of determinationf) What is the coefficient of correlationg) Interpret the coefficient of determinationh) Interpret the coefficient of correlation48. From the below cross classification showing the frequencies of hair and eye color of a group of students at North Texas, and answer the following questions (a-d). Eye ColorHair Color BlondBrownBlueGreenHazelTotalBlond30187257Brown7428107119Red/Auburn17155340Black43116161Total164722813277a) Probability that a student will have blue eyes given he/she is blond. b) Probability of black hair. c) Probability that a student will have either red hair or green eyes. d) Probability that a student will have brown hair and brown eyes. 49. Work on problem number 33 on page 5-19 (a-d)a)b)c)d)50. Work on problem number 17 on page 5-16 (a-e)a)b)c)d)e)