大学MOOC Business Statistics(Shanghai University of International Business and Economics)1458684162 最新慕课完整章节测试答案

Exercise 1

1、单选题：
 The process of using data collected from a small group to reach conclusions about a large group is called‏‏‏‏
选项：
A:  statistical inference.
B:  the scientific method.
C: sampling.
D: descriptive statistics.
答案: 【  statistical inference.】

2、单选题：
The estimation of the population's average family expenditure on food based on the sample average expenditure of 1,000 families is an example of‏‏‏‏​‏
选项：
A:  inferential statistics.
B:  descriptive statistics.
C:  a parameter.
D: a statistic.
答案: 【  inferential statistics.】

3、单选题：
The universe or "totality of items or things" under consideration is called‏‏‏‏‍‏
选项：
A: a sample.
B:  a population.
C:  a parameter.
D:  a statistic.
答案: 【  a population.】

4、单选题：
A summary measure that is computed to describe a characteristic of an entire population is called‌‌‌
选项：
A: a parameter.
B:  a census.
C: a statistic.
D: the scientific method.
答案: 【 a parameter.】

5、判断题：
‎A population is the totality of items or things under consideration.​
选项：
A: 正确
B: 错误
答案: 【 正确】

6、判断题：
​A sample is the portion of the universe that is selected for analysis.‏
选项：
A: 正确
B: 错误
答案: 【 正确】

7、判断题：
‎The possible responses to the question "How long have you been living at your current residence?" are values from a continuous variable.‏
选项：
A: 正确
B: 错误
答案: 【 正确】

8、判断题：
‏Student grades (A to F) are an example of continuous numerical data.‎
选项：
A: 正确
B: 错误
答案: 【 错误】

Exercise ch02

1、单选题：
The width of each bar in a histogram corresponds to the‏‏‏‏‏‏
选项：
A: differences between the boundaries of the class.
B:  number of observations in each class.
C:  midpoint of each class.
D:  percentage of observations in each class.
答案: 【 differences between the boundaries of the class.】

2、单选题：
When constructing charts, the following is plotted at the class midpoints:‌‌‌‌‎‌
选项：
A:  frequency histograms.
B:  percentage polygons.
C:  cumulative percentage polygon (ogives).
D:  pie chart
答案: 【  percentage polygons.】

3、单选题：
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.‌ ‌            Stem    Leaves     ‌            3          2 3‌            4          0 3 4 7 8 9 9 9‌            5          0 1 1 2 3 4 5‌            6          1 2 5 6 6‌            7          0 1‌            8         ‌            9          2‌what percentage of the respondents rated overall television quality with a rating of 80 or above?‌‌
选项：
A: 0
B: 4
C: 96
D: 100
答案: 【 4】

4、单选题：
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.‏ ‏            Stem    Leaves     ‏            3          2 3‏            4          0 3 4 7 8 9 9 9‏            5          0 1 1 2 3 4 5‏            6          1 2 5 6 6‏            7          0 1‏            8         ‏            9          2‏what percentage of the respondents rated overall television quality with a rating of 50 or below?‏‏‍‏
选项：
A: 11
B: 40
C: 44
D: 56
答案: 【 44】

5、单选题：
Data on 1,500 students' height were collected at a larger university in the East Coast. Which of the following is the best chart for presenting the information?‎‎‍‎
选项：
A:  a pie chart
B: a Pareto chart
C:  a side-by-side bar chart
D:  a histogram
答案: 【  a histogram】

6、单选题：
In a survey, 150 executives were asked what they think is the most common mistake candidates make during job interviews. Six different mistakes were given. Which of the following is the best for presenting the information?‎‎‎
选项：
A:  a bar chart
B:  a histogram
C: a stem-and-leaf display
D: a contingency table
答案: 【  a bar chart】

7、判断题：
‏The sum of relative frequencies in a distribution always equals 1.​
选项：
A: 正确
B: 错误
答案: 【 正确】

8、判断题：
​The sum of cumulative frequencies in a distribution always equals 1.‌
选项：
A: 正确
B: 错误
答案: 【 错误】

9、判断题：
‎One of the advantages of a pie chart is that it clearly shows that the total of all the categories of the pie adds to 100%.​
选项：
A: 正确
B: 错误
答案: 【 正确】

10、判断题：
‎The original data values cannot be determined once they are grouped into a frequency distribution table.‏
选项：
A: 正确
B: 错误
答案: 【 正确】

11、判断题：
‎The stem-and-leaf display is often superior to the frequency distribution in that it maintains the original values for further analysis.‌
选项：
A: 正确
B: 错误
答案: 【 正确】

12、判断题：
 The relative frequency is the frequency in each class divided by the total number of observations.‍‍‍
选项：
A: 正确
B: 错误
答案: 【 正确】

Exercise 3

1、单选题：
Which of the following statistics is NOT a measure of central tendency?‏‏‏‏​‏
选项：
A: arithmetic mean
B: median
C:  mode
D:  Q3
答案: 【  Q3】

2、单选题：
Which measure of central tendency can be used for both numerical and categorical variables?‌‌‌‍‌
选项：
A:  arithmetic mean
B:  median
C: mode
D:  standard deviation
答案: 【 mode】

3、单选题：
Which of the arithmetic mean, median, and mode are resistant measures of central tendency?‏‏‏​‏
选项：
A: the arithmetic only
B: the median only
C:  the mode mean only
D: the median and mode only
答案: 【 the median and mode only】

4、单选题：
In a right-skewed distribution,‎‎‎‌‎
选项：
A:  the median equals the arithmetic mean.
B:  the median is less than the arithmetic mean.
C:  the median is greater than the arithmetic mean.
D: none of the above
答案: 【  the median is less than the arithmetic mean.】

5、单选题：
When extreme values are present in a set of data, which of the following descriptive summary measures are most appropriate?‏‏‏
选项：
A:  CV and range
B:  arithmetic mean and standard deviation
C:  interquartile range and median
D: variance and interquartile range
答案: 【  interquartile range and median】

6、单选题：
In right-skewed distributions, which of the following is the correct statement?‏‏‏‌‏
选项：
A: The distance from Q1 to Q2 is greater than the distance from Q2 to Q3.
B: The distance from Q1 to Q2 is less than the distance from Q2 to Q3.
C: The arithmetic mean is less than the median.
D:  The mode is greater than the arithmetic mean.
答案: 【 The distance from Q1 to Q2 is less than the distance from Q2 to Q3.】

7、单选题：
According to the empirical rule, if the data form a "bell-shaped" normal distribution, ________ percent of the observations will be contained within 2 standard deviations around the arithmetic mean.‌‌‌‌‎‌
选项：
A:  68.26
B:  88.89
C:  93.75
D: 95.44
答案: 【 95.44】

8、判断题：
​The median of the values 3.4, 4.7, 1.9, 7.6, and 6.5 is 1.9.‎
选项：
A: 正确
B: 错误
答案: 【 错误】

9、判断题：
In a set of numerical data, the value for Q3 can never be smaller than the value for Q1.​‎​
选项：
A: 正确
B: 错误
答案: 【 正确】

10、判断题：
A boxplot is a graphical representation of a five-number summary.‍​‍
选项：
A: 正确
B: 错误
答案: 【 正确】

11、判断题：
In a boxplot, the box portion represents the data between the first and third quartile values.‎​‎
选项：
A: 正确
B: 错误
答案: 【 正确】

12、判断题：
The coefficient of variation measures variability in a data set relative to the size of the arithmetic mean.‏​‏
选项：
A: 正确
B: 错误
答案: 【 正确】

Exercise 4

1、单选题：
 If two events are collectively exhaustive, what is the probability that one or the other occurs?‏‏‍‏
选项：
A: 0
B: 0.5
C: 1
D: 1.5
答案: 【 1】

2、单选题：
If two events are mutually exclusive, what is the probability that both occur at the same time?‏‏‌‏
选项：
A: 0
B: 0.5
C: 1
D: cannot be determined from the information given
答案: 【 0】

3、单选题：
 If two events are independent, what is the probability that they both occur?​​​​
选项：
A: 0
B: 0.5
C: 1
D:  cannot be determined from the information given
答案: 【  cannot be determined from the information given】

4、单选题：
The collection of all possible events is called‏‏‏​‏
选项：
A:  a simple probability.
B:  a sample space.
C:  a joint probability.
D: the null set
答案: 【  a sample space.】

5、单选题：
When using the general multiplication rule, P(A and B) is equal to​​‍​
选项：
A: P(A|B)P(B).
B:  P(A)P(B).
C:  P(B)/P(A).
D: P(A)/P(B).
答案: 【 P(A|B)P(B).】

6、单选题：
The employees of a company were surveyed on questions regarding their educational background (college degree or no college degree) and marital status (single or married). Of the 600 employees, 400 had college degrees, 100 were single, and 60 were single college graduates. The probability that an employee of the company is single or has a college degree is ________.‌‌‍‌
选项：
A: 0.1
B: 0.25
C: 0.667
D: 0.733
答案: 【 0.733】

7、单选题：
According to a survey of American households, the probability that the residents own two cars if annual household income is over $50,000 is 80%. Of the households surveyed, 60% had incomes over $50,000 and 70% had two cars. The probability that the residents of a household do not own two cars and have an income over $50,000 a year is ________.‏‏
选项：
A: 0.12
B: 0.18
C: 0.22
D: 0.48
答案: 【 0.12】

8、单选题：
According to a survey of American households, the probability that the residents own two cars if annual household income is over $50,000 is 80%. Of the households surveyed, 60% had incomes over $50,000 and 70% had two cars. The probability that annual household income is over $50,000 if the residents of a household own two cars is ________.​​​​
选项：
A: 0.42
B: 0.48
C: 0.50
D: 0.69
答案: 【 0.69】

9、单选题：
According to a survey of American households, the probability that the residents own two cars if annual household income is over $50,000 is 80%. Of the households surveyed, 60% had incomes over $50,000 and 70% had two cars. The probability that the residents do not own two cars if annual household income is not over $50,000 is ________.‍‍
选项：
A: 0.12
B: 0.18
C: 0.45
D: 0.70
答案: 【 0.45】

10、判断题：
When A and B are mutually exclusive, P(A or B) can be found by adding P(A) and P(B).‏‍‏
选项：
A: 正确
B: 错误
答案: 【 正确】

11、判断题：
‏The collection of all the possible events is called a sample space.‌
选项：
A: 正确
B: 错误
答案: 【 正确】

12、判断题：
 If A and B cannot occur at the same time the events are called mutually exclusive.​‏​
选项：
A: 正确
B: 错误
答案: 【 正确】

13、判断题：
‌If P(A) = 0.4 and P(B) = 0.6, then A and B must be collectively exhaustive.​
选项：
A: 正确
B: 错误
答案: 【 错误】

Exercise 5

1、单选题：
A campus program evenly enrolls undergraduate and graduate students. If a random sample of four students is selected from the program to be interviewed about the introduction of a new fast food outlet on the ground floor of the campus building, what is the probability that all four students selected are undergraduate students?​​‌​
选项：
A: 0.0256
B: 0.0625
C: 0.16
D: 1
答案: 【 0.0625】

2、单选题：
The connotation "expected value" or "expected gain" from playing roulette at a casino means‌‌‌‌‎‌
选项：
A: the amount you expect to "gain" on a single play.
B:  the amount you expect to "gain" in the long run over many plays.
C: the amount you need to "break even" over many plays.
D: the amount you should expect to gain if you are lucky.
答案: 【  the amount you expect to "gain" in the long run over many plays.】

3、单选题：
 In a binomial distribution,​​​​‎​
选项：
A: the random variable X is continuous.
B:  the probability of event of interest π is stable from trial to trial.
C:  the number of trials n must be at least 30.
D: the results of one trial are dependent on the results of the other trials.
答案: 【  the probability of event of interest π is stable from trial to trial.】

4、单选题：
If the outcomes of a random variable follow a Poisson distribution, then their‍‍‍
选项：
A:  mean equals the standard deviation.
B: median equals the standard deviation.
C:  mean equals the variance.
D:  median equals the variance.
答案: 【  mean equals the variance.】

5、单选题：
he on-line access computer service industry is growing at an extraordinary rate. Current estimates suggest that 75% of the home-based computers have access to on-line services. Suppose 20 people with home-based computers were randomly and independently sampled. Find the probability that fewer than 10 of those sampled currently have access to on-line services.‎‎‏‎
选项：
A: 0.0031
B: 0.0026
C: 0.0145
D: 0.0039
答案: 【 0.0039】

6、单选题：
If n = 10 and P = 0.70, then the standard deviation of the binomial distribution is ________.​​‍​
选项：
A: 0.07
B: 1.45
C: 7
D: 14.29
答案: 【 1.45】

7、判断题：
The number of customers arriving at a department store in a five-minute period has a Poisson distribution.‎‏‎
选项：
A: 正确
B: 错误
答案: 【 正确】

8、判断题：
Another name for the mean of a probability distribution is its expected value.‍‍‍
选项：
A: 正确
B: 错误
答案: 【 正确】

9、判断题：
‎Suppose that a judge's decisions fol