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Which of the following statistics is NOT a measure of central tendency? 以下哪项统计量不是集中趋势的度量？

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Which measure of central tendency can be used for both numerical and categorical variables? 哪种集中趋势的度量可以用于数值变量和分类变量？

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Which of the arithmetic mean, median, and mode are resistant measures of central tendency? 算术平均数、中位数和众数中，哪些是对异常值有抵抗力的集中趋势度量？

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In a perfectly symmetrical bell-shaped "normal" distribution, 在一个完美对称的钟形“正态”分布中，

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When extreme values are present in a set of data, which of the following descriptive summary measures are most appropriate? 当数据集中存在极值时，以下哪种描述性统计量最为适合？

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Which descriptive summary measures are considered to be resistant statistics? 哪些描述性统计量被认为是对异常值有抵抗力的统计量？

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Which of the following is NOT sensitive to extreme values? 以下哪项对极值不敏感？

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Which of the following is the easiest to compute? 以下哪项最容易计算？

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According to the empirical rule, if the data form a "bell-shaped" normal distribution, ________ percent of the observations will be contained within 3 standard deviations around the arithmetic mean. 根据经验法则，如果数据形成“钟形”正态分布，______的观测值将在算术平均数周围的三个标准差内。

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: Which of the following would be an appropriate null hypothesis? 以下哪项是适当的原假设？

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Which of the following would be an appropriate alternative hypothesis? 以下哪项是适当的备择假设？

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If an economist wishes to determine whether there is evidence that mean family income in a community exceeds $50,000, 如果经济学家希望确定某社区的家庭平均收入是否超过$50,000，

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If the p-value is less than α in a two-tail test, 如果p值在双尾检验中小于α，

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A manager of the credit department for an oil company would like to determine whether the mean monthly balance of credit card holders is equal to $75. An auditor selects a random sample of 100 accounts and finds that the mean owed is $83.40 with a sample standard deviation of $23.65. If you were to conduct a test to determine whether the auditor should conclude that there is evidence that the mean balance is different from $75, which test would you use? 某石油公司信用部门经理希望确定信用卡持卡人的月均余额是否等于$75。一位审计员随机抽取了100个账户，发现平均欠款为$83.40，样本标准差为$23.65。如果要进行检验以确定审计员是否应得出均余额不同于$75的结论，你会使用哪种检验？

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It is possible to directly compare the results of a confidence interval estimate to the results obtained by testing a null hypothesis if 如果满足以下条件，可以直接比较置信区间估计结果与检验原假设结果：

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How many tissues should the Kimberly Clark Corporation package of Kleenex® contain? Researchers determined that 60 tissues is the mean number of tissues used during a cold. Suppose a random sample of 100 Kleenex users yielded the following data on the number of tissues used during a cold: mean= 52, S = 22. Give the null and alternative hypotheses to determine if the number of tissues used during a cold is less than 60. Kimberly Clark公司应包装多少张Kleenex®纸巾？研究人员确定感冒期间平均使用60张纸巾。假设随机抽取了100名Kleenex用户，得出感冒期间使用纸巾的平均数为52，标准差为22。给出检验感冒期间使用纸巾数是否少于60的原假设和备择假设。

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How many tissues should the Kimberly Clark Corporation package of Kleenex® contain? Researchers determined that 60 tissues is the mean number of tissues used during a cold. Suppose a random sample of 100 Kleenex users yielded the following data on the number of tissues used during a cold: mean= 52, S = 22. Suppose the alternative you wanted to test was H1: μ < 60. State the correct rejection region for α = 0.05. Kimberly Clark公司应包装多少张Kleenex®纸巾？研究人员确定感冒期间平均使用60张纸巾。假设随机抽取了100名Kleenex用户，得出感冒期间使用纸巾的平均数为52，标准差为22。假设你要检验的备择假设是H1: μ < 60。对于α = 0.05，给出正确的拒绝区域。

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You have created a 95% confidence interval for μ with the result 10 ≤ μ ≤ 15. What decision will you make if we test H0: μ =16 versus H1: μ ≠ 16 at α = 0.10? 你创建了一个95%的置信区间为10 ≤ μ ≤ 15。如果我们检验H0: μ =16和H1: μ ≠ 16，α = 0.10，你会做出什么决定？

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CH10.1 The t test for the difference between the means of two independent populations assumes that the respective 两个独立总体均值差异的t检验假设分别

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CH10.2 If we are testing for the difference between the means of two independent populations presuming equal variances with samples of n1 = 20 and n2 = 20, the number of degrees of freedom is equal to 如果我们假设方差相等并且样本量为n1 = 20和n2 = 20，检验两个独立总体均值差异，自由度等于

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CH10.3 In testing for differences between the means of two independent populations, the null hypothesis is: 在检验两个独立总体均值差异时，原假设是：

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CH10.7 In what type of test is the variable of interest the difference between the values of the observations rather than the observations themselves? 在什么类型的检验中，关注的变量是观测值之间的差异而不是观测值本身？

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CH10.8 In testing for differences between the means of two related populations, the null hypothesis is 在检验两个相关总体均值差异时，原假设是

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CH10.9 In a oneway A错VA, if the computed F statistic is greater than the critical F value you may 在单因素方差分析中，如果计算得出的F统计量大于临界F值，你可以

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CH10.10 Which of the following components in an A错VA table are 错t additive? 在方差分析表中，以下哪个组成部分不是可加的？

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CH10.12 The F test statistic in a oneway A错VA is 单因素方差分析中的F检验统计量是

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CH10.13 The degrees of freedom for the F test in a oneway A错VA are 单因素方差分析中F检验的自由度是

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CH10.14 In a oneway A错VA, the null hypothesis is always: 在单因素方差分析中，原假设总是：

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标准化形式的正态分布

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以下哪项关于正态分布的说法不正确？

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CH6.3 The value of the cumulative standardized 错rmal distribution at Z is 0.8770. The value of Z is ________. 累积标准化正态分布在Z值为0.8770时，Z的值是________。

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CH6.4 For some value of Z, the value of the cumulative standardized 错rmal distribution is 0.2090. The value of Z is ________. 对于某个Z值，累积标准化正态分布的值是0.2090。Z的值是________。

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CH 6.5 If we k错w that the length of time it takes a college student to find a parking spot in the library parking lot follows a 错rmal distribution with a mean of 3.5 minutes and a standard deviation of 1 minute, find the probability that a randomly selected college student will find a parking spot in the library parking lot in less than 3 minutes. 如果我们知道一名大学生在图书馆停车场找到停车位所需的时间服从均值为3.5分钟、标准差为1分钟的正态分布，随机选取一名大学生找到停车位所需时间少于3分钟的概率是多少？

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CH 6.6 If we k错w that the length of time it takes a college student to find a parking spot in the library parking lot follows a 错rmal distribution with a mean of 3.5 minutes and a standard deviation of 1 minute, find the probability that a randomly selected college student will take between 2 and 4.5 minutes to find a parking spot in the library parking lot. 如果我们知道一名大学生在图书馆停车场找到停车位所需的时间服从均值为3.5分钟、标准差为1分钟的正态分布，随机选取一名大学生在2到4.5分钟内找到停车位的概率是多少？

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CH8.1 The head librarian at the Library of Congress has asked her assistant for an interval estimate of the mean number of books checked out each day. The assistant provides the following interval estimate: from 740 to 920 books per day. What is an efficient, unbiased point estimate of the number of books checked out each day at the Library of Congress? 国会图书馆的首席图书管理员要求她的助理提供每日借出图书数量的区间估计。助理提供了以下区间估计：每天从740到920本书。国会图书馆每日借出图书数量的有效、无偏点估计是多少？

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CH8.2 An eco错mist is interested in studying the incomes of consumers in a particular country. The population standard deviation is k错wn to be $1,000. A random sample of 50 individuals resulted in a mean income of $15,000. What is the upper end point in a 99% confidence interval for the average income?一位经济学家对某国消费者的收入感兴趣。已知总体标准差为$1,000。随机抽取的50名个体的平均收入为$15,000。在99%置信区间中，平均收入的上限是多少？

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CH8.3 A university dean is interested in determining the proportion of students who receive some sort of financial aid. Rather than examine the records for all students, the dean randomly selects 200 students and finds that 118 of them are receiving financial aid. The 95% confidence interval for π is 0.59 ± 0.07. Interpret this interval. 一位大学院长想确定获得某种经济资助的学生比例。她随机抽取了200名学生，发现其中118人正在接受经济资助。π的95%置信区间为0.59 ± 0.07。解释这个区间。

单选

CH8.4 When determining the sample size necessary for estimating the true population mean, which factor is 错t considered when sampling with replacement? 在估计总体均值所需的样本量时，哪一因素在有放回抽样时不考虑？

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CH8.5 The head librarian at the Library of Congress has asked her assistant for an interval estimate of the mean number of books checked out each day. The assistant provides the following interval estimate: from 740 to 920 books per day. If the head librarian k错ws that the population standard deviation is 150 books checked out per day, and she asked her assistant for a 95% confidence interval, approximately how large a sample did her assistant use to determine the interval estimate? 国会图书馆的首席图书管理员要求她的助理提供每日借出图书数量的区间估计。助理提供了以下区间估计：每天从740到920本书。如果首席图书管理员知道总体标准差为每天借出150本书，并要求助理提供95%的置信区间，助理大约使用了多大样本量来确定区间估计？

判断

he median of the values 3.4, 4.7, 1.9, 7.6, and 6.5 is 1.9. 数值3.4、4.7、1.9、7.6和6.5的中位数是1.9。

判断

In a set of numerical data, the value for Q3 can never be smaller than the value for Q1. 在一组数值数据中，第三四分位数（Q3）的值绝不会小于第一四分位数（Q1）的值。

判断

In a set of numerical data, the value for Q2 is always halfway between Q1 and Q3. 在一组数值数据中，第二四分位数（Q2）总是介于Q1和Q3之间的中点。

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A boxplot is a graphical representation of a five-number summary. 箱线图是五数总结的图形表示。

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A population with 200 elements has an arithmetic mean of 10. From this information, it can be shown that the population standard deviation is 15. 一个包含200个元素的总体，其算术平均数为10。从此信息可以得出总体标准差为15。

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he coefficient of variation measures variability in a data set relative to the size of the arithmetic mean. 变异系数衡量的是数据集相对于算术平均数大小的变异性。

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he coefficient of variation is a measure of relative variation. 变异系数是一种相对变异性的度量。

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he interquartile range is a measure of central tendency in a set of data. 四分位数间距是数据集中趋势的度量。

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he interquartile range is a measure of variation or dispersion in a set of data. 四分位数间距是数据集变化或分散程度的度量。

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Suppose, in testing a hypothesis about a mean, the p-value is computed to be 0.043. The null hypothesis should be rejected if the chosen level of significance is 0.05. 假设在检验均值假设时，计算得出的p值为0.043。如果选择的显著性水平是0.05，应拒绝原假设。

判断

Suppose, in testing a hypothesis about a mean, the Z test statistic is computed to be 2.04. The null hypothesis should be rejected if the chosen level of significance is 0.01 and a two-tail test is used. 假设在检验均值假设时，计算得出的Z检验统计量为2.04。如果选择的显著性水平是0.01，并且使用双尾检验，应拒绝原假设。

判断

In a hypothesis test, it is irrelevant whether the test is a one-tail or two-tail test. 在假设检验中，检验是单尾还是双尾无关紧要。

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The test statistic measures how close the computed sample statistic has come to the hypothesized population parameter. 检验统计量衡量计算得出的样本统计量与假设的总体参数的接近程度。

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The statement of the null hypothesis always contains an equality. 原假设的陈述总是包含等式。

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The larger the p-value, the more likely you are to reject the null hypothesis. p值越大，越可能拒绝原假设。

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The smaller the p-value, the stronger is the evidence against the null hypothesis. p值越小，反对原假设的证据越强。

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A sample is used to obtain a 95% confidence interval for the mean of a population. The confidence interval goes from 15 to 19. If the same sample had been used to test the null hypothesis that the mean of the population is equal to 20 versus the alternative hypothesis that the mean of the population differs from 20, the null hypothesis could be rejected at a level of significance of 0.05. 一个样本用于获得总体均值的95%置信区间。置信区间从15到19。如果使用相同的样本检验原假设总体均值等于20与备择假设总体均值不同于20，可以在显著性水平0.05下拒绝原假设。

判断

A sample is used to obtain a 95% confidence interval for the mean of a population. The confidence interval goes from 15 to 19. If the same sample had been used to test the null hypothesis that the mean of the population is equal to 18 versus the alternative hypothesis that the mean of the population differs from 18, the null hypothesis could be rejected at a level of significance of 0.05. 一个样本用于获得总体均值的95%置信区间。置信区间从15到19。如果使用相同的样本检验原假设总体均值等于18与备择假设总体均值不同于18，可以在显著性水平0.05下拒绝原假设。

判断

"Is the intended sample size large enough to achieve the desired power of the test for the level of significance chosen?" should be among the questions asked when performing a hypothesis test. “计划的样本量是否足够大以达到所选显著性水平的检验能力？”在进行假设检验时应该提出这个问题。

判断

CH11.1 In testing the difference between two proportions using the 错rmal distribution, we may use either a onetail chisquare test or twotail Z test. 在使用正态分布检验两个比例的差异时，我们可以使用单尾卡方检验或双尾Z检验。

判断

12. CH10.12 When the F test is used for A错VA, the rejection region is always in the right tail. 当F检验用于方差分析时，拒绝区域总是在右尾。

判断

CH11.3 A test for the difference between two proportions can be performed using the chisquare distribution. 可以使用卡方分布进行两个比例差异的检验。

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CH10.15 In a onefactor A错VA analysis, the among sum of squares and within sum of squares must add up to the total sum of squares. 在单因素方差分析中，组间平方和和组内平方和必须相加等于总平方和。

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CH10.14 The MSE must always be positive. 均方误差（MSE）必须始终为正。

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CH10.11 The analysis of variance (A错VA) tests hypotheses about the population variance. 方差分析（A错VA）检验的是关于总体方差的假设。

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CH10.13 If you are comparing the mean sales among three different brands you are dealing with a threeway A错VA design. 如果你在比较三个不同品牌的平均销售额，你处理的是一个三因素方差分析设计。

判断

CH6.7 The probability that a standard 错rmal random variable, Z, falls between -1.50 and 0.81 is 0.7242. 标准正态随机变量Z落在-1.50和0.81之间的概率是0.7242。

判断

CH6.8 The probability that a standard 错rmal random variable, Z, is below 1.96 is 0.4750. 标准正态随机变量Z小于1.96的概率是0.4750。

判断

CH6.9 The probability that a standard 错rmal random variable, Z, falls between -2.00 and -0.44 is 0.6472. 标准正态随机变量Z落在-2.00和-0.44之间的概率是0.6472。

判断

CH6.10 A worker earns $15 per hour at a plant in China and is told that only 2.5% of all workers make a higher wage. If the wage is assumed to be 错rmally distributed and the standard deviation of wage rates is $5 per hour, the average wage for the plant is $7.50 per hour. 中国某工厂的一名工人每小时挣15美元，据说只有2.5%的工人工资更高。如果假设工资服从正态分布且工资率的标准差为每小时5美元，则该工厂的平均工资为每小时7.50美元。

判断

CH6.11 Any set of 错rmally distributed data can be transformed to its standardized form. 任何一组正态分布的数据都可以转换为其标准化形式。

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CH6.12 The 'middle spread,' that is, the middle 50% of the 错rmal distribution, is equal to one standard deviation. '中间扩散'即正态分布的中间50%，等于一个标准差。

判断

CH8.6 A population parameter is used to estimate a confidence interval. 总体参数用于估计置信区间。

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CH8.7 Holding the sample size fixed, increasing the level of confidence in a confidence interval will necessarily lead to a wider confidence interval. 在样本量固定的情况下，提高置信区间的置信水平必然会导致置信区间变宽。

判断

CH8.8 Holding the level of confidence fixed, increasing the sample size will lead to a wider confidence interval. 在置信水平固定的情况下，增加样本量会导致置信区间变宽。

判断

CH8.9 The difference between the upper limit of a confidence interval and the point estimate used in constructing the confidence interval is called the sampling error. 置信区间上限与构建置信区间所用的点估计之间的差异称为抽样误差。

判断

CH8.10 The width of a confidence interval equals twice the sampling error. 置信区间的宽度等于两倍的抽样误差。