大学MOOC 商务统计(吉林师范大学)1456480165 最新慕课完整章节测试答案

第一单元测试

1、单选题：
‎The general process of gathering, organizing, summarizing, analyzing, and interpreting data to assist in making effective decisions is called:‏
选项：
A: statistics.
B: descriptive statistics.
C: inferential statistics.
D: levels of measurement.
答案: 【 statistics.】

2、单选题：
‌A sample is:​
选项：
A: at least 15 observations.
B: a group of people.
C: part of a population.
D: a set of frequencies.
答案: 【 part of a population.】

3、单选题：
The main purpose of inferential statistics is to:‏‏
选项：
A: summarize data in a useful and informative manner.
B: estimate population characteristics based on a sample information.
C: determine if the data adequately represents the population.
D: gather or collect data.
答案: 【 estimate population characteristics based on a sample information.】

4、单选题：
‏To study the characteristics of loan applicants, a random sample of 50 loan applicants is selected and their annual incomes are obtained. Which level of measurement is annual income?‍
选项：
A: Nominal
B: Ordinal
C: Interval
D: Ratio
答案: 【 Ratio】

5、单选题：
‍The main purpose of descriptive statistics is to:‍
选项：
A: summarize data in a useful and informative manner.
B: estimate a population characteristic based on a sample.
C: determine if the data adequately represents the population.
D: gather or collect data.
答案: 【 summarize data in a useful and informative manner.】

6、单选题：
‏A bank asks customers to evaluate the quality of drive-through service as good, average, or poor. Which level of measurement is used to measure service quality?‌
选项：
A: Nominal
B: Ordinal
C: Interval
D: Ratio
答案: 【 Ordinal】

7、单选题：
The main purpose of descriptive statistics is to:‌‌
选项：
A: summarize data in a useful and informative manner.
B: estimate a population characteristic based on a sample.
C: determine if the data adequately represents the population.
D: gather or collect data.
答案: 【 summarize data in a useful and informative manner.】

8、单选题：
‍Gallup political polls ask people their political party affiliation - Democrat, Republican or Independent. Which level of measurement is used to measure party affiliation?‎
选项：
A: Nominal
B: Ordinal
C: Interval
D: Ratio
答案: 【 Nominal】

9、单选题：
‍What type of variable is: number of car accidents reported in your city?‏
选项：
A: Attribute
B: Continuous
C: Discrete
D: Qualitative
答案: 【 Discrete】

10、单选题：
‎Data measured with an ordinal scale:‍
选项：
A: can be ranked.
B: have a meaningful value of zero.
C: have meaningful differences between values.
D: are quantitative.
答案: 【 can be ranked.】

补充测试

1、单选题：
‌The general process of gathering, organizing, summarizing, analyzing, and interpreting data to assist in making effective decisions is called:​
选项：
A: statistics
B: descriptive statistics
C: inferential statistics
D: levels of measurement
答案: 【 statistics】

2、单选题：
‍A sample is:‎
选项：
A: at least 15 observations
B: a group of people
C: part of a population
D: a set of frequencies
答案: 【 part of a population】

3、单选题：
‌The main purpose of inferential statistics is to:‌
选项：
A: summarize data in a useful and informative manner.
B: estimate population characteristics based on a sample information.
C: determine if the data adequately represents the population.
D: gather or collect data.
答案: 【 estimate population characteristics based on a sample information.】

4、单选题：
‍To study the characteristics of loan applicants, a random sample of 50 loan applicants is selected and their annual incomes are obtained. Which level of measurement is annual income?‎
选项：
A: Nominal
B: Ordinal
C: Interval
D: Ratio
答案: 【 Ratio】

5、单选题：
‍The main purpose of descriptive statistics is to:​
选项：
A: summarize data in a useful and informative manner.
B: estimate a population characteristics based on a sample.
C: determine if the data adequately represents the population.
D: gather of collect data.
答案: 【 summarize data in a useful and informative manner.】

6、单选题：
‏A bank asks customers to evaluate the quality of drive-through service as good, average, or poor. Which level of measurement is used to measure service quality?‍
选项：
A: Nominal
B: Ordinal
C: Interval
D: Ratio
答案: 【 Ordinal】

7、单选题：
‌Gallup political polls ask people their political party affiliation- Democrat, Republican or Independent. Which level of measurement is used to measure party affiliation?​
选项：
A: Nominal
B: Ordinal
C: Interval
D: Ratio
答案: 【 Nominal】

8、单选题：
​What type of variable is: number of car accidents reported in your city?‎
选项：
A: Attribute
B: Continuous
C: Discrete
D: Qualitative
答案: 【 Discrete】

9、单选题：
‍Data measured with an ordinal scale:‎
选项：
A: can be ranked.
B: have a meaningful value of zero.
C: have meamingful differences between values.
D: are quantitative.
答案: 【 can be ranked.】

10、单选题：
‏The main purpose of descriptive statistics is to:‌‏‌
选项：
A: summarize data in a useful and informative manner.
B: estimate a population characteristic based on a sample.
C: determine if the data adequately represents the population.
D: gather or collect data.
答案: 【 summarize data in a useful and informative manner.】

第二单元测验

1、单选题：
‏In a frequency distribution the classes must:‎
选项：
A: be mutually exclusive.
B: have a maximum of 10 observations.
C: have equal frequencies.
D: be measured on a nominal scale.
答案: 【 be mutually exclusive.】

2、单选题：
‍For a frequency distribution, the class interval is:‎
选项：
A: the class frequencies divided by two.
B: the class frequency divided by the number of observations.
C: the difference between consecutive lower class limits.
D: the number of observations in the class.
答案: 【 the difference between consecutive lower class limits.】

3、单选题：
‏For a frequency distribution, a class frequency is:​
选项：
A: the number of observations in the class.
B: the difference between consecutive lower class limits.
C: limited to a maximum of 10 observations.
D: the total number of observations in the sample.
答案: 【 the number of observations in the class.】

4、单选题：
​A research organization is studying the selling price of laptop computers. They selected 25 different computers for the study. To summarize the selling price with a frequency distribution and using the 2k rule, how many classes would you recommend?‏
选项：
A: 10
B: 25
C: 4
D: 5
答案: 【 5】

5、单选题：
‍For a frequency distribution, the class midpoint is:​
选项：
A: the class interval divided by two and added to the lower limit.
B: the difference between consecutive lower limits.
C: the number of observations in the class.
D: the class frequency divided by the number of observations.
答案: 【 the class interval divided by two and added to the lower limit.】

6、单选题：
‌Which of the following is not a guideline for a frequency distribution?​
选项：
A: Avoid open-ended classes.
B: Use the 2k rule to determine the number of classes.
C: Make the lower limit of the first class a multiple of the class interval.
D: Each class should have more than 5 observations.
答案: 【 Each class should have more than 5 observations.】

7、单选题：
‍To convert a frequency distribution to a relative frequency distribution:‏
选项：
A: find the difference between consecutive lower class limits.
B: divide the class frequency by the total number of observations.
C: divide the lower limit of the first class by the class interval.
D: multiple the class frequency by 100.
答案: 【 divide the class frequency by the total number of observations.】

8、单选题：
​A pie chart shows:‏
选项：
A: the frequency for each class.
B: the relative frequency for each class.
C: trends in the data.
D: the class midpoints.
答案: 【 the relative frequency for each class.】

9、单选题：
The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier.‌ ‌                                                Relative‌            Time (in Minutes)        Frequency     ‌            0 but less than 5          0.37‌            5 but less than 10        0.22‌            10 but less than 15      0.15‌            15 but less than 20      0.10‌            20 but less than 25      0.07‌            25 but less than 30      0.07‌            30 or more                   0.02‌ Referring to the table, if 1,000 calls were randomly sampled, how many calls lasted under 10 minutes?‌
选项：
A: 220
B: 370
C: 410
D: 590
答案: 【 590】

10、单选题：
‎In a cumulative frequency polygon:‌
选项：
A: the class frequencies are converted to percents.
B: the cumulative frequency for the first class limit is zero.
C: we add the class frequencies starting with the first class.
D: all of the above.
答案: 【 all of the above.】

测验1

1、单选题：
‌In a positively skewed  distribution​‌​
选项：
A: the median equals the arithmetic mean.
B: the median is less than the arithmetic mean.
C: the median is larger than the arithmetic mean.
D: none of the above.
答案: 【 the median is less than the arithmetic mean.】

2、单选题：
‏In a perfectly symmetrical bell-shaped "normal" distribution‌
选项：
A: the arithmetic mean equals the median.
B: the median equals the mode.
C: the arithmetic mean equals the mode.
D: All the above.
答案: 【 All the above.】

3、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】

4、判断题：
​The median of a data set with 20 items would be  the average of the 10th and the 11th items in the ordered array.‎​‎
选项：
A: 正确
B: 错误
答案: 【 正确】

5、判断题：
‌If a set of data is perfectly symmetrical, the arithmetic mean must be identical to the median.‍
选项：
A: 正确
B: 错误
答案: 【 正确】

6、判断题：
​ In a  sample of size 40, the sample mean is 15. In this case, the sum of all  observations in the sample is  600.‌​‌
选项：
A: 正确
B: 错误
答案: 【 正确】

7、填空题：
The data below represent the amount of grams of carbohydrates in a serving of breakfast cereal in a sample of 11 different servings.‏‏11  15  23  29  19  22  21  20  15  25  17‏the arithmetic mean carbohydrates in this sample is ________ grams.‏
答案: 【 19.73】

8、填空题：
The data below represent the amount of grams of carbohydrates in a serving of breakfast cereal in a sample of 11 different servings.‍ ‍11  15  23  29  19  22  21  20  15  25  17‍ the median carbohydrate amount in the cereal is ________ grams.‍
答案: 【 20】

第三单元测验

1、单选题：
‌A key difference between calculating the sample mean and the population mean is:​
选项：
A: we use  and n instead of μ and N.
B: we divide the sum of the observations by n - 1 instead of n.
C: the sample observations are ranked and the middle value is selected as the population mean.
D: there are no differences.
答案: 【 we use  and n instead of μ and N.】

2、单选题：
‍Which of the following measures of central location is affected most by extreme values?‏
选项：
A: Median
B: Mean
C: Mode
D: Variance
答案: 【 Mean】

3、单选题：
‏The Empirical Rule states that:‍
选项：
A: for a bell shaped frequency distribution, approximately 68% of the observations are in the range of plus or minus one standard deviation.
B: for a positively skewed frequency distribution, approximately 68% of the observations are in the range of plus or minus one standard deviation.
C: for a bell shaped frequency distribution, approximately 75% of the observations are in the range of plus or minus one standard deviation.
D: for a positively skewed frequency distribution, approximately 75% of the observations are in the range of plus or minus one standard deviation.
答案: 【 for a bell shaped frequency distribution, approximately 68% of the observations are in the range of plus or minus one standard deviation.】

4、单选题：
‍Which measure of central tendency reports the value that occurs with the highest frequency?‍
选项：
A: Mean
B: Median
C: Mode
D: Standard deviation
答案: 【 Mode】

5、单选题：
‍An example of Chebyshev's Theorem is:‏
选项：
A: for a bell shaped frequency distribution, at least 95% of the observations are in the range of plus or minus two standard deviations from the mean.
B: for a negatively skewed frequency distribution, at least 95% of the observations are in the range of plus or minus two standard deviations from the mean.
C: for any frequency distribution, at least 75% of the observations are in the range of plus or minus two standard deviations from the mean.
D: for a positively skewed frequency distribution, at least 68% of the observations are in the range of plus or minus two standard deviations from the mean.
答案: 【 for any frequency distribution, at least 75% of the observations are in the range of plus or minus two standard deviations from the mean.】

6、单选题：
‌In comparing two different samples of 100 observations, sample "A" has a mean of 10 and a standard deviation of 10. The sample "B" has a mean of 10 and a standard deviation of 50. The two samples are:‌
选项：
A: exactly the same.
B: are centered at 10, but sample "A"s data is more concentrated near the mean.
C: are centered at 10, but sample "B"s data is more concentrated near the mean.
D: positively skewed.
答案: 【 are centered at 10, but sample "A"s data is more concentrated near the mean.】

7、单选题：
‏‍For a distribution, the mean is 5, the median is 15, and the mode is 20. Based on this information, the distribution is:‍‏‍‏‍
选项：
A: positively skewed.
B: negatively skewed.
C: symmetric.
D: bell-shaped.
答案: 【 negatively skewed.】

8、单选题：
‍In a positively skewed distribution, which measure of central tendency is the largest?‌
选项：
A: Mean
B: Median
C: Mode
D: Variance
答案: 【 Mean】

9、单选题：
‏Which of the following statistics is a measure of dispersion?‎
选项：
A: Mean
B: Median
C: Mode
D: Standard deviation
答案: 【 Standard deviation】

10、单选题：
‍What is true about the range?‌
选项：
A: Only two values are used in its calculation.
B: It is in different units than the mean.
C: It can be used for nominal data.
D: All values are used in its calculation.
答案: 【 Only two values are used in its calculation.】

第四单元测验

1、单选题：
A dot plot shows:‌‌
选项：
A: the general shape of a distribution.
B: the mean, median, and mode.
C: the relationship between two variables.
D: the interquartile range.
答案: 【 the general shape of a distribution.】

2、单选题：
The test scores for a class of 101 students are computed. What is the location of the test score associated with the third quartile?‏‏
选项：
A: 75%
B: 31
C: 50.0
D: 76.5
答案: 【 76.5】

3、单选题：
‏The test scores for a class of 50 students are computed. What is the location of the test score associated with the second decile?‍
选项：
A: 20%
B: 31
C: 10.2
D: 20.5
答案: 【 10.2】

4、单选题：
‎To summarize a data set with a box plot:‌
选项：
A: two values are required: the 1st quartile and the 3rd quartile.
B: three values are required: the minimum, median, and maximum.
C: four values are required: the minimum, 1st quartile, 3rd quartile, and maximum.
D: five values are required: the minimum, 1st quartile, median, 3rd quartile, and maximum.
答案: 【 five values are required: the minimum, 1st quartile, median, 3rd quartile, and maximum.】

5、单选题：
‍For a data set, the interquartile range is:‌
选项：
A: the difference between the minimum and maximum values.
B: the standard deviation.
C: the difference between the 1st and 3rd quartiles.
D: the skewness of a distribution.
答案: 【 the difference between the 1st and 3rd quartiles.】

6、单选题：
‎For any symmetric distribution:‎
选项：
A: The mean, median, and mode are equal.
B: Compared to the median and mode, the mean is the largest measure of location.
C: Compared to the mean and mode, the median is the largest measure of location.
D: Compared to the mean, median, and mode, the standard deviation is the largest value.
答案: 【 The mean, median, and mode are equal.】

7、单选题：
‎For a data set, the coefficient of skewness is -2.73. We conclude that:​
选项：
A: the mean is larger than the median.
B: the median is larger than the mean.
C: the standard deviation is a less than zero.
D: something is wrong because the coefficient of skewness cannot be less than -1.00.
答案: 【