CƠ SỞ II TRƯỜNG ĐẠI HỌC NGOẠI THƯƠNG BỘ MÔN KINH DOANH & THƯƠNG MẠI QUỐC TẾ ĐỀ THI KẾT THÚC HỌC PHẦN NGUYÊN LÝ THỐNG KÊ KINH TẾ – TOAE301 _________________________ __________________________________ Học kỳ :1 Năm học: 2021 – 2022 Hệ: Chính quy Mã lớp tín chỉ: 184 Khóa: 58 Ngày thi: 26/09/2021 Ca thi:10h15-11h20 Hình thức thi : Trắc nghiệm và tự luận Thời gian làm bài: 65 phút (không kể thời gian phát đề) ĐỀ SỐ:1 SECTION A. MULTIPLE CHOICE (2 points) There are 10 questions in this section. Each question is worth 0.2 points. Q1. A statistics professor surveys the students in her class and finds that 20% are sophomores and 45% are juniors. This is an example of: A) nominal data. B) descriptive statistics. C) secondary data. D) inferential statistics. Q2. The grades that a random sample of MBA students received over the last five years of “International Business” classes represent what statistical concept? A) The grades are a sample. B) The grades are a parameter. C) The grades are a population. D) The grades are a statistic. Q3. A newspaper advertising sales representative earns a commission on each advertisement sold. This person made $3,000 in commissions during one month and concludes that annual compensation will be $36,000. This is an example of: A) secondary data. B) inferential statistics C) nominal data. D) descriptive statistics. Q4. A consumer confidence researcher asks several retailers to report the number of LCD televisions sold during a particular month. These numbers most likely represent what level of measurement? A) Interval B) Nominal C) Ordinal D) Ratio Q5. Student evaluation of teaching effectiveness for a particular course asks students to respond to their level of agreement with several statements according to the scale 1 = Strongly Agree, 2 = Agree, 3 = Neutral, 4 = Disagree, and 5 = Strongly Disagree. The responses indicate what level of measurement? 1 A) Interval B) Nominal C) Ordinal D) Ratio Q6. Look at the survey questions that a firm sent to its customers. What type of variable and levels of measurement do the questions concerning overall service, selection, and quality of the items purchased represent? A) Categorical variables measured on the interval scale. B) Continuous variables measured on a ratio scale. C) Categorical variables measured on an ordinal scale. D) Categorical variables measured on the nominal scale. Q7. The Quality Assurance Department of a large urban hospital is attempting to monitor and evaluate patient satisfaction with hospital services. Prior to discharge, a random sample of patients is asked to fill out a questionnaire to rate such services as medical care, nursing, therapy, laboratory, food, and cleaning. The Quality Assurance Department prepares weekly reports that are presented at the Board of Directors meetings and extraordinary/atypical ratings are easy to flag. True population characteristics estimated from the sample results each week are called ________. A) a sample. B) a population. C) a parameter. D) a statistic Q8. Which of the following is most likely a parameter as opposed to a statistic? A) The average score of the first five students completing an assignment. B) The proportion of females registered to vote in a county. C) The average height of people randomly selected from a database. D) The proportion of trucks stopped yesterday that were cited for bad brakes. Q9. The chancellor of a major university was concerned about alcohol abuse on her campus and wanted to find out the proportion of students at her university who visited campus bars on the weekend before the final exam week. Her assistant took a random sample of 250 students and computed the portion of students in the sample who visited campus bars on the weekend before the final exam. The portion of all students at her university who visited campus bars on the weekend before the final exam week is an example of: A) a statistic. B) a population. C) a sample. D) a parameter. Q10. The average number of units earned per semester by college students is suspected to be rising. A researcher at Calendula College wishes to estimate the number of units earned by students during the spring semester at Calendula. To do so, he randomly selects 100 student transcripts and records the number of units each student earned in the spring term. Identify the variable of interest to the researcher. A) The number of students enrolled at Calendula College during the spring term. B) The average indebtedness of Calendula College students enrolled in the spring. C) The age of Calendula College students enrolled in the spring. D) The number of units earned by Calendula College students during the spring term. 2 SECTION B. SHORT ESSAY QUESTIONS AND CALCULATION TASKS (8 points) Problem 1: (3 points) A manufacturer of industrial wheels suspects that profitable orders are being lost because of the long time the firm takes to develop price quotes for potential customers. To investigate this possibility, 50 requests for price quotes were randomly selected from the set of all quotes made last year, and the processing time (in days) was determined for each quote. Each quote was classified according to whether the order was “lost” or not (i.e., whether or not the customer placed an order after receiving a price quote). A. B. C. D. E. F. Describe the process studied. (0.2 points) Describe the research question. (0.2 points) Describe the variables of interest. (0.4 points) Describe the measurement of the variables in C. (0.4 points) Describe the population and sample. (0.4 points) Use the descriptive statistics on the processing time of the lost orders and the placed orders to answer the research question (1.4 point). Mean Standard deviation Number of observations Placed orders 4.44 Lost orders 11.82 1.973 4.194 39 11 Problem 2: (2 points) At one university, the students are given z-scores at the end of each semester rather than the traditional GPAs. The mean and standard deviation of all students’ cumulative GPAs, on which the z-scores are based, are 2.7 and 0.5, respectively. A. Students with z-scores below −1.6 are put on probation. What is the corresponding probationary GPA? (0.5 points) B. The president of the university wishes to graduate the top 16% of the students with cum laude honors and the top 2.5% with summa cum laude honors. Where (approximately) should the limits be set in terms of z-scores? (0.5 points) In terms of GPAs? (0.5 points) What assumption, if any, did you make about the distribution of the GPAs at the university? (0.5 points) Problem 3 (3 points): We use data on SAT score and estimate the equation: 𝑠𝑎𝑡 = 𝛽0 + 𝛽1 ℎ𝑠𝑖𝑧𝑒 + 𝛽2 ℎ𝑠𝑖𝑧𝑒𝑠𝑞 + 𝛽3 𝑓𝑒𝑚𝑎𝑙𝑒 + 𝛽4 𝑏𝑙𝑎𝑐𝑘 + 𝑢 (1) where: sat = combined SAT score hsize = size of the student’s high school graduating class, in hundreds hsizesq =hsize2 female =1 for female, 0 otherwise black = 1 for blacks, 0 otherwise The results are presented in column (1) in the table below: 3 Regression results VARIABLES hsize hsizesq female black (1) Model 1 (2) Model 2 19.11 (3.837) -2.189 (0.528) -41.61 (4.175) -139.3 (9.097) 19.30 (3.832) -2.195 (0.527) -45.09 (4.291) -169.8 (12.71) 62.31 (18.15) 1,028 (6.290) female*black Constant 1,027 (6.290) Observations 4,137 4,137 R-squared 0.083 0.086 F-statistics 93.72 77.52 Prob > F 0.000 0.000 Standard errors in parentheses A. Discuss the results in column (1). (2 points) B. Suppose that we add an interaction between female and black in the model as below: sat = 0 + 1hsize+ 2 hsizesq+ 3 female + 4 black + 5 female* black + u (2) The estimated results are presented in column (2). Holding other factors fixed, what is the estimated difference in SAT score between nonblack females and nonblack males? Explain (0.5 points). How statistically significant is this estimated difference? (0.5 points) --------------------------------------End of test-------------------------------------Note: - This paper contains 10 questions from Section A, 03 problem from Section B, 04 pages. - Students are not allowed to use materials during the examination. - Invigilators shall not provide further explanation. APPROVAL COURSE DIRECTOR (or DEAN/VICE DEAN OF THE FACULTY) LE HONG VAN 4 LECTURER