商务统计期中考试试题Part I: 单选题 (每题2分，共60分)1. The universe or totality of items or things under consideration is calleda) a sample.b) a population.c) a parameter.d) a statistic.2. Which of the following is most likely a population as opposed to a sample?a) respondents to a newspaper survey.b) the first 5 students completing an assignment.c) every third person to arrive at the bank.d) registered voters in a county.3. A study is under way in Yosemite National Forest to determine the adult height of American pine trees. Specifically, the study is attempting to determine what factors aid a tree in reaching heights greater than 60 feet tall. It is estimated that the forest contains 25,000 adult American pines. The study involves collecting heights from 250 randomly selected adult American pine trees and analyzing the results. Identify the variable of interest in the study.a) The age of an American pine tree in Yosemite National Forest.b) The height of an American pine tree in Yosemite National Forest.c) The number of American pine trees in Yosemite National Forest.d) The species of trees in Yosemite National Forest.4. The British Airways Internet site provides a questionnaire instrument that can be answered electronically. Which of the 4 methods of data collection is involved when people complete the questionnaire?a) Published sourcesb) Experimentationc) Surveyingd) Observation5. To monitor campus security, the campus police office is taking a survey of the number of students in a parking lot each 30 minutes of a 24-hour period with the goal of determining when patrols of the lot would serve the most students. If X is the number of students in the lot each period of time, then X is an example ofa) a categorical random variable.b) a discrete random variable.c) a continuous random variable.d) a statistic.6. An insurance company evaluates many numerical variables about a person before deciding on an appropriate rate for automobile insurance. A representative from a local insurance agency selected a random sample of insured drivers and recorded, X, the number of claims each made in the last 3 years, with the following results.Xfrequency1142183 124551Referring to the table, how many total claims are represented in the sample?a) 15b) 50c) 111d) 250(For Q7 and Q8) A survey was conducted to determine how people rated the quality of programming available on television. Respondents were asked to rate the overall quality from 0 (no quality at all) to 100 (extremely good quality). The stem-and-leaf display of the data is shown below.StemLeaves3244034789995011234561256670189 27. Referring to the table, what percentage of the respondents rated overall television quality with a rating of 80 or above?a) 0b) 4c) 96d) 1008. Referring to the table, what percentage of the respondents rated overall television quality with a rating between 50 and 75?a) 11b) 40c) 44d) 56(For Q9 and Q10) The following are the durations in minutes of a sample of long-distance phone calls made reported by one long-distance carrier.Time (in Minutes)Relative Frequency0 but less than 50.375 but less than 100.2210 but less than 150.1515 but less than 200.1020 but less than 250.0725 but less than 300.0730 more0.029. Referring to the table, if 1,000 calls were randomly sampled, how many calls lasted under 10 minutes?a) 220b) 370c) 410d) 59010. Referring to the table, if 100 calls were randomly sampled, how many calls lasted 15 minutes or longer?a) 10b) 14c) 26d) 7411. You have collected data on the approximate retail price (in $) and the energy cost per year (in $) of 15 refrigerators. Which of the following is the best for presenting the data?a) A pie chart.b) A scatter diagram.c) A Pareto diagram.d) A contingency table.(For Q12 and Q13) The histogram below represents scores achieved by 200 job applicants on a personality profile.12. Referring to the histogram, _ percent of the job applicants scored between 10 and 20.a) 10%b) 20%c) 30%d) 40%13. Referring to the histogram, the number of job applicants who scored between 30 and below 60 is _.a) 20b) 40c) 60d) 8014. Which measure of central tendency can be used for both numerical and categorical variables?a) Arithmetic mean.b) Median.c) Mode.d) Standard deviation.15. Which of the following statements about the median is not true?a) It is more affected by extreme values than the arithmetic mean.b) It is a measure of central tendency.c) It is equal to Q2.d) It is equal to the mode in bell-shaped normal distributions.16. When extreme values are present in a set of data, which of the following descriptive summary measures are most appropriate:a) CV and range.b) arithmetic mean and standard deviation.c) in