商务统计学试卷E答案

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商务统计实务-参考答案

商务统计实务参考答案项目1一、名词解释（略）二、选择题1．B2．C3．A4．D5．B6．A7．B8．C9．B10．C三、判断题1．错2．对3．错4．错5．对6．错7．对8．错四、简答题（略）项目2一、名词解释（略）二、选择题1．D2．C3．B4．C三、判断题1．错2．错3．错4．错5．对6．对7．对8．错9．错四、简答题（略）项目3一、名词解释（略）二、选择题1．A2．D3．C4．A5．C6．D7．B三、判断题1．错2．错3．对4．错5．错6．对7．错8．错9．对10．对11．错四、简答题（略）项目4一、名词解释（略）二、选择题1．A2．C3．B4．D5．B6．D三、判断题1．错2．错3．错4．对5．对6．错7．对8．错9．对10．错11．对四、简答题（略）项目5一、名词解释（略）二、选择题1．D2．B3．B4．B5．D6．C7．C8．B9．C三、判断题1．错2．对3．对4．对5．对6．错7．错8．错四、简答题（略）项目6 略项目7一、名词解释（略）二、选择题1．D2．C3．A4．D5．ABD6．ABC三、判断题1．对2．错3．对4．错四、简答题（略）项目8一、名词解释（略）二、选择题1．D2．C3．B4．D5．A三、简答题（略）项目9一、名词解释（略）二、选择题1．A2．B3．B4．A5．B6．A7．D8．B9．C10．A11．D12．A13．B14．A15．C16．B17．D18．B19．B三、判断题1．错2．错3．错4．错5．错6．对7．错8．错9．对四、简答题（略）项目10一、名词解释（略）二、选择题1. B2．C3.C4.A5.B6.A7.D8.B9.D10.B三、判断题1．错2．对3．错4．错5．错6．对四、简答题（略）项目11一、名词解释（略）二、选择题1．C2.B3.D4.C5.D6. B三、判断题1．对2．错3．错4．错5．对6．错7．错四、简答题（略）项目12一、名词解释（略）二、选择题1．A2.C3.B4.B5.D6.A7.B8. C三、判断题1．错2．对3．对4．对5．对6．对7．对8．错9．对四、简答题（略）。

商务统计选择答案.doc

Part One: Multiple Choices:1.The probability that a continuous random variable takes any specific valuea.is equal to zerob.is at least 0.5c.depends on the probability density functiond.is very close to 1.02. A normal distribution with a mean of 0 and a standard deviation of 1 is calleda. a probability density functionb.an ordinary normal curvec. a standard normal distributiond.none of these alternatives is correct3. A negative value of Z indicates thata.the number of standard deviations of an observation is to the right of the meanb.the number of standard deviations of an observation is to the left of the meanc. a mistake has been made in computations, since Z cannot be negatived.the data has a negative mean4.For a continuous random variable x, the probability density function f(x) representsa.the probability at a given value of xb.the area under the curve at xc.the area under the curve to the right of xd.the height of the function at x5.For the standard normal probability distribution, the area to the left of the mean isa.-0.5b.0.5c.any value between 0 to 1d. 1rger values of the standard deviation result in a normal curve that isa.shifted to the rightb.shifted to the leftc.narrower and more peakedd.wider and flatter7. A continuous probability distribution that is useful in describing the time, or space,between occurrences of an event is a(n)a.normal probability distributionb.uniform probability distributionc.exponential probability distributiond.Poisson probability distribution8.Consider a binomial probability experiment with n = 3 and p = 0.1. Then, the probabilityof x = 0 isa.0.0000b.0.0001c.0.001d.0.7299. A continuous random variable may assumea.all values in an interval or collection of intervalsb.only integer values in an interval or collection of intervalsc.only fractional values in an interval or collection of intervalsd.all the positive integer values in an interval10.The highest point of a normal curve occurs ata.one standard deviation to the right of the meanb.two standard deviations to the right of the meanc.approximately three standard deviations to the right of the meand.the meanExhibit 1The assembly time for a product is uniformly distributed between 6 to 10 minutes.11.Refer to Exhibit 1. The probability density function has what value in the interval between 6 and 10?a.0.25b. 4.00c. 5.00d.zero12.Refer to Exhibit 1. The probability of assembling the product between 7 to 9 minutes isa.zerob.0.50c.0.20d. 113.Refer to Exhibit 1. The probability of assembling the product in less than 6 minutes isa.zerob.0.50c.0.15d. 114.Refer to Exhibit 1. The probability of assembling the product in 7 minutes or more isa.0.25b.0.75c.zerod. 115.Refer to Exhibit 1. The expected assembly time (in minutes) isa.16b. 2c.8d. 416.Refer to Exhibit 1. The standard deviation of assembly time (in minutes) is approximatelya. 1.3333b. 1.1547c.0.1111d.0.577317.Center of a normal curve isa.always equal to zerob.is the mean of the distributionc.cannot be negatived.is the standard deviation18.The uniform, normal, and exponential distributions area.all continuous probability distributionsb.all discrete probability distributionsc.can be either continuous or discrete, depending on the datad.all the same distributions19.Which of the following is not a characteristic of the normal probability distribution?a.The mean, median, and the mode are equalb.The mean of the distribution can be negative, zero, or positivec.The distribution is symmetricald.The standard deviation must be 120.In a standard normal distribution, the range of values of z is froma.minus infinity to infinityb.-1 to 1c.0 to 1d.-3.09 to 3.0921.Parameters area.numerical characteristics of a sampleb.numerical characteristics of a populationc.the averages taken from a sampled.numerical characteristics of either a sample or a population22.How many simple random samples of size 3 can be selected from a population of size 7?a.7b.21c.35d.34323. A population consists of 500 elements. We want to draw a simple random sample of 50 elements from this population. On the first selection, the probability of an element being selected isa.0.100b.0.010c.0.001d.0.00224.The closer the sample mean is to the population mean,a.the larger the sampling errorb.the smaller the sampling errorc.the sampling error equals 1d.None of these alternatives is correct.25.Since the sample size is always smaller than the size of the population, the sample meana.must always be smaller than the population meanb.must be larger than the population meanc.must be equal to the population meand.can be smaller, larger, or equal to the population mean26.As the sample size increases, thea.standard deviation of the population decreasesb.population mean increasesc.standard error of the mean decreasesd.standard error of the mean increases27. A simple random sample from an infinite population is a sample selected such thata.each element is selected independently and from the same populationb.each element has a 0.5 probability of being selectedc.each element has a probability of at least 0.5 of being selectedd.the probability of being selected changes28.In point estimationa.data from the population is used to estimate the population parameterb.data from the sample is used to estimate the population parameterc.data from the sample is used to estimate the sample statisticd.the mean of the population equals the mean of the sample29.The sample mean is the point estimator ofa.pib.Gc.xd.-P30.The expected value of the random variable x isa.the standard errorb.the sample sizec.the size of the populationd.None of these alternatives is correct.31.The standard deviation of all possible x values is called thea.standard error of proportionb.standard error of the meanc.mean deviationd.central variation32.Whenever the population has a normal probability distribution, the sampling distribution of x is a normal probability distribution fora.only large sample sizesb.only small sample sizesc.any sample sized.only samples of size thirty or greater33.The sampling error is thea.same as the standard error of the meanb.difference between the value of the sample mean and the value of the population meanc.error caused by selecting a bad sampled.standard deviation multiplied by the sample size34.Which of the following is(are) point estimator(s)?a. ab.p,c.sd.a35. A population characteristic, such as a population mean, is calleda. a statisticb. a parameterc. a sampled.the mean deviation36. A single numerical value used as an estimate of a population parameter is known asa. a parameterb. a population parameterc. a mean estimatord. a point estimate37.The purpose of statistical inference is to provide information about thea.sample based upon information contained in the populationb.population based upon information contained in the samplec.population based upon information contained in the populationd.mean of the sample based upon the mean of the population38.The number of random samples (without replacement) of size 3 that can be drawn from a population of size 5 isa.15b.10c.20d.12539.For a population with any distribution, the form of the sampling distribution of the sample mean isa.sometimes normal for all sample sizesb.sometimes normal for large sample sizesc.always normal for all sample sizesd.always normal for large sample sizes40. A simple random sample of 28 observations was taken from a large population. The sample mean equaled 50. Fifty is aa.population parameterb.biased estimate of the population meanc.sample parameterd.point estimate41.When s is used to estimate G, the margin of error is computed by usinga.normal distributionb.t distributionc.the mean of the sampled.the mean of the population42.From a population with a variance of 900, a sample of 225 items is selected. At 95% confidence, the margin of error isa.15b. 2c. 3.92d. 443.In order to determine an interval for the mean of a population with unknown standard deviation a sample of 61 items is selected. The mean of the sample is determined to be 23. The number of degrees of freedom for reading the t value isa.22b.23c.60d.6144.If we want to provide a 95% confidence interval for the mean of a population, the confidence coefficient isa.0.485b. 1.96c.0.95d. 1.64545.As the number of degrees of freedom for a t distribution increases, the difference between the t distribution and the standard normal distributiona.becomes largerb.becomes smallerc.stays the samed.None of these alternatives is correct.46.For the interval estimation of p, when o is known and the sample is large, the proper distribution to use isa.the normal distributionb.the t distribution with n degrees of freedomc.the t distribution with n + 1 degrees of freedomd.the t distribution with n + 2 degrees of freedom47.An estimate of a population parameter that provides an interval of values believed to contain the value of the parameter is known as thea.confidence levelb.interval estimatec.parameter valued.population estimate48.The value added and subtracted from a point estimate in order to develop an interval estimate of the population parameter is known as thea.confidence levelb.margin of errorc.parameter estimated.interval estimate49.If an interval estimate is said to be constructed at the 90% confidence level, the confidence coefficient would bea.0.1b.0.95c.0.9d.0.0550.Whenever the population standard deviation is unknown and the population has a normal or near-normal distribution, which distribution is used in developing an interval estimation?a.standard distributionb.z distributionc.alpha distributiond.t distribution51.In interval estimation, the t distribution is applicable only whena.the population has a mean of less than 30b.the sample standard deviation is used to estimate the population standard deviationc.the variance of the population is knownd.the standard deviation of the population is known52.In developing an interval estimate, if the population standard deviation is unknowna.it is impossible to develop an interval estimateb.the standard deviation is arrived at using the rangec.the sample standard deviation can be usedd.it is assumed that the population standard deviation is 153.In order to use the normal distribution for interval estimation of)i when cr is known and the sample is very small, the populationa.must be very largeb.must have a normal distributionc.can have any distributiond.must have a mean of at least 154.From a population that is not normally distributed and whose standard deviation is not known, a sample of 6 items is selected to develop an interval estimate for the mean of the population (y).a.The normal distribution can be used.b.The t distribution with 5 degrees of freedom must be used.c.The t distribution with 6 degrees of freedom must be used.d.The sample size must be increased.55.From a population that is normally distributed, a sample of 25 elements is selected and the standard deviation of the sample is computed. For the interval estimation of pi, the proper distribution to use is thea.normal distributionb.t distribution with 25 degrees of freedomc.t distribution with 26 degrees of freedomd.t distribution with 24 degrees of freedom56.As the sample size increases, the margin of errora.increasesb.decreasesc.stays the samed.increases or decreases depending on the size of the mean57. A 95% confidence interval for a population mean is determined to be 100 to 120. If the confidence coefficient is reduced to 0.90, the interval for(ia.becomes narrowerb.becomes widerc.does not changed.becomes 0.158.The ability of an interval estimate to contain the value of the population parameter is described by thea.confidence levelb.degrees of freedomc.precise value of the population mean p,d.degrees of freedom minus 159.An interval estimate is a range of values used to estimatea.the shape of the population's distributionb.the sampling distributionc. a sample statisticd. a population parameter60.In determining the sample size necessary to estimate a population proportion, which of the following information is not needed?a.the maximum margin of error that can be toleratedb.the confidence level requiredc. a preliminary estimate of the true population proportion Pd.the mean of the population61.What type of error occurs if you fail to reject H o when, in fact, it is not true?a.Type IIb.Type Ic.either Type I or Type II, depending on the level of significanced.either Type I or Type II, depending on whether the test is one tail or two tail62.An assumption made about the value of a population parameter is called aa.hypothesisb.conclusionc.confidenced.significance63.The probability of committing a Type I error when the null hypothesis is true isa.the confidence levelb.卩c.greater than 1d.the Level of Significance64.The p-value is a probability that measures the support (or lack of support) for thea.null hypothesisb.alternative hypothesisc.either the null or the alternative hypothesisd.sample statistic65.The p-valuea.is the same as the Z statisticb.measures the number of standard deviations from the meanc.is a distanced.is a probability66.In hypothesis testing if the null hypothesis is rejected,a.no conclusions can be drawn from the testb.the alternative hypothesis is truec.the data must have been accumulated incorrectlyd.the sample size has been too small67.The level of significance is thea.maximum allowable probability of Type II errorb.maximum allowable probability of Type I errorc.same as the confidence coefficientd.same as the p-value68. A Type II error is committed whena. a true alternative hypothesis is mistakenly rejectedb. a true null hypothesis is mistakenly rejectedc.the sample size has been too smalld.not enough information has been available69.The level of significancea.can be any positive valueb.can be any valuec.is (1 - confidence level)d.can be any value between -1.96 to 1.9670.When the following hypotheses are being tested at a level of significance of aH o: pi > 500H a: ]i < 500the null hypothesis will be rejected if the p-value isa.< aH a : ]i > 10.0%H a : |i > 10.0%H a : ]i < 10.0%d. Ho ： pi > 10.0% H a : ]i < 10.0%a. Ho ： pi < 85 H a : pi > 85b. Ho ： pi < 85 H a : p, >c. Ho ： pi > 85 H a : p, < 85d. Ho ： pi > 85 H a : pi < 85 a. Ho ：pi < 12 H a : pi < 12b. Ho ： pi < 12 H a : p, >c. Ho： pi H 12H a : p, = 12b. > ac. > a/2d. < 1 - a/271. When the p-value is used for hypothesis testing, the null hypothesis is rejected if a. p-value < ab. a < p-valuec. p-value > ad. p-value = 1 - a72. In order to test the following hypotheses at an a level of significanceH o : pi < 800H a : ]i > 800the null hypothesis will be rejected if the test statistic Z isa. 巴 Z Qb. <Z ac. < -Z ad. = a73. Your investment executive claims that the average yearly rate of return on the stocks she recommends is more than 10.0%. You plan on taking a sample to test her claim. The correct setof hypotheses is a. H o : pi < 10.0% b. Ho ： pi < 10.0%c. Ho ： pi > 10.0%74. A weatherman stated that the average temperature during July in Chattanooga is less than 80 degrees. A sample of 32 Julys is taken. The correct set of hypotheses is a . H o : pi > 80 H a : p, <80 b . H o : pi < 80 H a : p, >80 c . H o : —80 H a : p, =80 d . H o : pi < 80 H a : p, >80 75. A student believes that the average grade on the final examination in statistics is at least85. She plans on taking a sample to test her belief. The correct set of hypotheses is76. A soft drink filling machine, when in perfect adjustment, fills the bottles with 12 ouncesof soft drink. Any over filling or under filling results in the shutdown and readjustment of the machine. To determine whether or not the machine is properly adjusted, the correct set ofhypotheses is d. Ho ： p = 1277. A two-tailed test is performed at 95% confidence. The p-value is determined to be 0.09. The null hypothesisa.must be rejectedb.should not be rejectedc . could be rejected, depending on the sample sized . has been designed incorrectly7 8Exhibit 2n = 49 x = 54.8 s = 28 H o: pi < 50H a: p, > 50Refer to Exhibit 2. The test statistic isa . 0.1714b . 0.3849c . -1.2d . 1.27 9Refer to Exhibit 2. The p-value is betweena . 0.01 to 0.025b . 0.025 to 0.05c . .05 to 0.1d . 0.1 to 0.28 0Refer to Exhibit 2. If the test is done at the 5% level of significance, the null hypothesisshoulda . not be rejectedb . be rejectedc . Not enough information given to answer this question.d . None of these alternatives is correct.8 1If we are interested in testing whether themeanof population 1 is significantly largerthanthe mean of population 2, thea . null hypothesis should state 内-应 > 0b . null hypothesis should state 内-应巴0c . alternative hypothesis should state p，i - |i2 > 0d . alternative hypothesis should state pii -112 < 08 2If we are interested in testing whether themeanof population 1 is significantlydifferentfrom the mean of population 2, thea . null hypothesis should state 山-应=0b . null hypothesis should state 山-应巴0c . alternative hypothesis should state p，i - |i2 > 0d . alternative hypothesis should state pii -112 < 08 3When developing an interval estimate for the difference between two sample means, withsample sizes of m and n2,a . Ni must be equal to n2b . Ni must be smaller than n2c . Ni must be larger than n2d . Ni and n2 can be of different sizes,84.Independent simple random samples are taken to test the difference between the means of two populations whose variances are not known, but are assumed to be equal. The samplesizes are m = 32 and n2 = 40. The correct distribution to use is thea.t distribution with 73 degrees of freedomb.t distribution with 72 degrees of freedomc.t distribution with 71 degrees of freedomd.t distribution with 70 degrees of freedom85.If two independent large samples are taken from two populations, the sampling distribution of the difference between the two sample meansa.can be approximated by a Poisson distributionb.will have a variance of onec.can be approximated by a normal distributiond.will have a mean of one86.The standard error of x -x2 is thea.--variance of x 严Qb.--variance of the sampling distribution of 区厂乂？c.- ~standard deviation of the sampling distribution of x 严？d.difference between the two means87.In the analysis of variance procedure (ANOVA), ''factor'' refers toa.the dependent variableb.the independent variablec.different levels of a treatmentd.the critical value of F88.The ANOVA procedure is a statistical approach for determining whether or nota.the means of two samples are equalb.the means of two or more samples are equalc.the means of more than two samples are equald.the means of two or more populations are equal89.An experimental design where the experimental units are randomly assigned to the treatments is known asa.factor block designb.random factor designpletely randomized designd.None of these alternatives is correct.90.In an analysis of variance problem involving 3 treatments and 10 observations per treatment, SSE = 399.6. The MSE for this situation isa.133.2b.199.8c.14.8d.30.04 4 4 191.The F ratio in a completely randomized ANOVA is the ratio ofa.MSTR/MSEb.MST/MSEc.MSE/MSTRd.MSE/MST92.The critical F value with 6 numerator and 60 denominator degrees of freedom at a = .05 isa. 3.74b. 2.25c. 2.37d. 1.9693.An ANOVA procedure is applied to data obtained from 6 samples where each sample contains 20 observations. The degrees of freedom for the critical value of F area. 6 numerator and 20 denominator degrees of freedomb. 5 numerator and 20 denominator degrees of freedomc. 5 numerator and 114 denominator degrees of freedomd. 6 numerator and 20 denominator degrees of freedom94.In an analysis of variance problem if SST = 120 and SSTR = 80, then SSE isa.200b.40c.80d.12095.An ANOVA procedure is used for data that was obtained from four sample groups each comprised of five observations. The degrees of freedom for the critical value of F area. 3 and 20b. 3 and 16c. 4 and 17d. 3 and 1996.In ANOVA, which of the following is not affected by whether or not the population means are equal?a.xb.between-samples estimate of c>2c.within-samples estimate of c>2d.None of these alternatives is correct.97. A term that means the same as the term "variable" in an ANOVA procedure isa.factorb.treatmentc.replicationd.variance withinExhibit 3Salary information regarding male and female employees of a large company is shown below.Male FemaleSample Size 64 36Sample Mean Salary (in $1,000)Population Variance (cr2) 128 7298.Refer to Exhibit 3. The point estimate of the difference between the means of the two populations isa.-28b. 3c. 4d.-499.Refer to Exhibit 3. The standard error for the difference between the two means isa. 4b.7.46c. 4.24d. 2.0100.Refer to Exhibit 3. At 95% confidence, the margin of error isa. 1.96b. 1.645c. 3.920d. 2.000101.The coefficient of determinationa.cannot be negativeb.is the square root of the coefficient of correlationc.is the same as the coefficient of correlationd.can be negative or positive102.If the coefficient of determination is a positive value, then the coefficient of correlationa.must also be positiveb.must be zeroc.can be either negative or positived.must be larger than 1103.The mathematical equation relating the independent variable to the expected value of the dependent variable; that is, E(y) = P0 + 卩lx, is known asa.regression equationb.correlation equationc.estimated regression equationd.regression model104.The model developed from sample data that has the form of y = + ijX is known asa.regression equationb.correlation equationc.estimated regression equationd.regression model105.The interval estimate of the mean value of y for a given value of x isa.prediction interval estimateb.confidence interval estimatec.average regressiond.x versus y correlation interval106.The interval estimate of an individual value of y for a given value of x isa.prediction interval estimateb.confidence interval estimatec.average regressiond.x versus y correlation interval107.In a regression analysis the standard error is determined to be 4. In this situation the MSEa.is 2b.is 16c.depends on the sample sized.depends on the degrees of freedom108.In regression analysis, which of the following is not a required assumption about the error term £?a.The expected value of the error term is one.b.The variance of the error term is the same for all values of X.c.The values of the error term are independent.d.The error term is normally distributed.109.In a regression analysis, the coefficient of determination is 0.4225. The coefficient of correlation in this situation isa.0.65b.0.1785c.any positive valued.any value110.In a regression analysis, the coefficient of correlation is 0.16. The coefficient of determination in this situation isa.0.4000b.0.0256c. 4d. 2.56111.In a regression and correlation analysis if r2 = 1, thena.SSE must also be equal to oneb.SSE must be equal to zeroc.SSE can be any positive valued.SSE must be negative112.In a regression and correlation analysis if r2 = 1, thena.SSE = SSTb.SSE= 1c.SSR = SSEd.SSR = SST113.If the coefficient of correlation is a positive value, then the regression equationa.must have a positive slopeb.must have a negative slopec.could have either a positive or a negative sloped.must have a positive y intercept114.If the coefficient of correlation is 0.& the percentage of variation in the dependent variable explained by the variation in the independent variable isa.0.80%b.80%c.0.64%d.64%115.In regression and correlation analysis, if SSE and SST are known, then with this information thea.coefficient of determination can be computedb.slope of the line can be computedc.Y intercept can be computedd.x intercept can be computed116.In regression analysis, if the independent variable is measured in pounds, the dependent variablea.must also be in poundsb.must be in some unit of weightc.cannot be in poundsd.can be any units117.If the coefficient of correlation is -0.4, then the slope of the regression linea.must also be -0.4b.can be either negative or positivec.must be negatived.must be 0.16118.If the coefficient of correlation is a negative value, then the coefficient of determinationa.must also be negativeb.must be zeroc.can be either negative or positived.must be positive119.If a data set has SSR = 400 and SSE = 100, then the coefficient of determination isa.0.10b.0.25c.0.40d.0.80pared to the confidence interval estimate for a particular value of y (in a linear regression model), the interval estimate for an average value of y will bea.narrowerb.widerc.the samed.None of these alternatives is correct.。

《商务统计学》题集

《商务统计学》题集一、选择题（每题2分，共10分）1.下列哪项不属于商务统计学的应用范围？A. 市场调查B. 质量控制C. 财务分析D. 天气预测2.在统计学中，总体是指什么？A. 研究的全部对象B. 研究中的一部分对象C. 某个具体的样本D. 某一特定数据3.下列哪种抽样方法是随机抽样？A. 方便抽样B. 系统抽样C. 配额抽样D. 判断抽样4.如果一组数据的均值是20，中位数是22，那么这组数据的分布可能是？A. 正偏态B. 负偏态C. 对称分布D. 无法确定5.在回归分析中，解释变量和被解释变量分别是什么？A. 因变量和自变量B. 自变量和因变量C. 都是自变量D. 都是因变量二、填空题（每空1分，共10分）1.在统计学中，用来衡量数据分布集中趋势的指标有______、______和______。

2.若一组数据的四分位数Q1=10，Q2=20，Q3=30，则该组数据的中位数为______。

3.在假设检验中，如果P值小于显著性水平α，则我们______原假设。

4.统计表中，频数和频率分别表示数据的______和______。

5.在回归分析中，回归系数的经济意义是解释变量每增加一个单位，被解释变量平均增加______单位。

三、判断题（每题1分，共10分）1.统计学的目的是收集、整理、分析和解释数据，从而帮助人们做出决策。

（）2.在正态分布中，均值、中位数和众数三者相等。

（）3.标准差是衡量数据波动大小的一个重要指标，标准差越大，说明数据的波动越大。

（）4.在假设检验中，如果P值大于显著性水平α，则我们有足够的证据拒绝原假设。

（）5.相关系数r的取值范围是[-1, 1]，r=1表示完全正相关，r=-1表示完全负相关。

（）6.如果一组数据的偏度系数大于0，则说明这组数据是正偏态分布。

（）7.在抽样调查中，样本容量越大，抽样误差就越小。

（）8.统计推断是通过样本数据来推断总体的特征。

（）9.移动平均法是一种常用的时间序列预测方法。

商务经济统计试题及答案

商务经济统计试题及答案一、单项选择题1. 商务统计中，用于描述数据集中趋势的指标是：A. 方差B. 标准差C. 平均数D. 众数答案：C2. 在商务经济统计中，下列哪项不是统计量？A. 均值B. 标准差C. 样本容量D. 极差答案：C3. 以下哪项不是时间序列分析的类型？A. 季节性分析B. 趋势分析C. 相关性分析D. 循环分析答案：C二、多项选择题1. 商务统计中，以下哪些因素会影响数据的变异性？A. 数据的分布形态B. 数据的集中趋势C. 数据的离散程度D. 数据的样本大小答案：A、C2. 在进行商务经济预测时，常用的统计方法包括：A. 回归分析B. 指数平滑法C. 移动平均法D. 季节性调整答案：A、B、C三、简答题1. 简述商务统计中的指数平滑法的基本原理。

答案：指数平滑法是一种时间序列预测方法，它通过对历史数据加权平均来预测未来值。

权重随着时间的递减而递减，即近期的数据比远期的数据在预测中占有更大的权重。

这种方法可以平滑掉数据中的随机波动，从而更好地反映数据的趋势。

2. 描述商务统计中相关系数的计算方法及其意义。

答案：相关系数是用来衡量两个变量之间线性关系强度和方向的统计量。

其计算公式为：\[ r = \frac{\sum (X_i - \bar{X})(Y_i -\bar{Y})}{\sqrt{\sum (X_i - \bar{X})^2 \sum (Y_i -\bar{Y})^2}} \] 其中，$ X_i $ 和 $ Y_i $ 分别是两个变量的观测值，$ \bar{X} $ 和 $ \bar{Y} $ 是它们的平均值。

相关系数的值介于-1和1之间，值越接近1或-1表示变量间的线性关系越强，正值表示正相关，负值表示负相关。

四、计算题1. 假设有一组商务数据，其平均值为100，标准差为15。

如果某次测量结果为120，计算该结果的Z分数。

答案：Z分数的计算公式为：\[ Z = \frac{(X - \mu)}{\sigma} \]其中，$ X $ 是测量结果，$ \mu $ 是平均值，$ \sigma $ 是标准差。

商务统计试题及答案

商务统计试题及答案### 商务统计试题及答案#### 一、选择题1. 统计数据收集的方法不包括以下哪项？- A. 观察法- B. 实验法- C. 调查法- D. 假设法答案：D2. 以下哪项不是描述性统计分析的内容？- A. 数据的分类- B. 数据的汇总- C. 数据的推断- D. 数据的图表展示答案：C3. 在统计学中，中位数是指：- A. 数据集中出现次数最多的数值- B. 数据集的算术平均值- C. 将数据集从小到大排列后位于中间位置的数值 - D. 所有数据的和除以数据的个数答案：C#### 二、简答题1. 解释什么是标准差，并简述其在商务统计中的重要性。

标准差是衡量一组数据离散程度的统计量，它表示数据集中的数值与平均值的偏差平方的平均数的平方根。

在商务统计中，标准差用于评估数据的波动性，帮助决策者了解业务风险和市场波动。

2. 描述相关系数的概念及其在商务分析中的应用。

相关系数是度量两个变量之间线性关系强度和方向的统计指标。

在商务分析中，相关系数可以用来评估不同因素对业务结果的影响，例如，销售额与广告支出之间的关系。

#### 三、计算题1. 给定以下数据集：10, 12, 15, 20, 25, 请计算平均值、中位数和标准差。

- 平均值 = (10 + 12 + 15 + 20 + 25) / 5 = 18- 中位数 = 15（数据集从小到大排列后位于中间位置的数值）- 标准差= √[(Σ(xi - 平均值)²) / n] = √[(10 - 18)² + (12 - 18)² + ... + (25 - 18)²] / 5 ≈ 5.392. 假设某公司连续5个月的销售额分别为：30万、35万、40万、45万和50万。

计算这5个月的平均销售额和销售额的增长趋势。

- 平均销售额 = (30 + 35 + 40 + 45 + 50) / 5 = 40万- 销售额的增长趋势可以通过计算每月销售额的增长率来分析，例如，从第一个月到第二个月的增长率为 (35 - 30) / 30 * 100% = 16.67%。

商务统计学试卷E

C.当标志值较小而次数较多时，平均数接近于标志值较小的一方
D.当标志值较大而次数较少时，平均数接近于标志值较大的一方
E.没有影响
6、标志变异指标可以反映（）
A.平均数代表性的大小B.生产过程的均衡性与产品质量的稳定性
C.反映现象的集中趋势D.反映现象的离中趋势
E.既反映集中趋势，又反映离中趋势
7、如果用p表示商品价格，q表示商品销售量，则公式的意义是（）
C.总体质的特征的名称D.总体量的特征的名称
2、第五次全国人口普查是( )。
A.重点调查B.典型调查C.一次性调查D.经常性调查
3、按数量标志分组时，确定组距的基本原则是（）。
A.各组的组距应当相近或相等B.各组的组距应当有明显的差别
C.要尽可能保持各组内的同质性和组间的差异性
D.要尽可能分出组与组之间数量上的差异
2、重点调查的特点是（）
A.重点单位的数目占总体单位总数很少
B.主要目的是要了解调查对象的基本情况
C.重点单位的标志值总量占总体标志总量的绝大比重
D.用来推算总体的指标值
E.选取有典型代表意义的单位
3、下列分组属于按数量标志分组的有（）
A.按性别分组B.按年龄分组C.按地区分区
D.按工资分组E.按百分制成绩分组
4、时期指标的数Biblioteka （）A.可以连续计量B.反映现象在某一时期内发展状况的总量
C.相邻两时期指标具有可加性D.其数值的大小与时间长短相关
E.其数值的大小与时间长短无关
5、次数对平均数的影响作用表现为（）
A.当标志值较大而次数较多时，平均数接近于标志值较大的一方
B.当标志值较小而次数较少时，平均数接近于标志值较小的一方
3.资料：某企业资料如下：

商务统计学试题

商务统计学[单项选择题]1、在数据采集活动中，进行观测记录的单位与总体中的个体（）A.必须相同B.必须不同C.可以相同，也可以不同D.完全没有关系参考答案：C[单项选择题]2、对于内部差异很大且有明显的不同类型界限或标志的总体，进行抽样调查应该采用的抽样方式是（）A.简单随机抽样B.系统抽样C.分层抽样D.整群抽样参考答案：C[单项选择题]3、如果观测变量的取值很多且数值成比例变化，则编制次数分布表时采用（）A.单值B.等距分组C.异距分组D.复合分组参考答案：C[单项选择题]4、统计指标是用来测度统计活动研究对象某种特征数量的（）A.概念B.数值C.概念和数值D.数值尺度参考答案：A[单项选择题]5、统计推断是一种（）A.演绎推理B.完全归纳推理C.不完全归纳推理D.非逻辑推理参考答案：C[单项选择题]6、根据斯特吉斯公式，对于样本容量为1000的一个观测样本，采用等距分组，其组数应该为（）A.9组B.10组C.11组D.12组参考答案：C[单项选择题]7、对于由观测变量的各个分组和各组变量总值顺序排列的分组分布表，计算算术平均数需采用的计算公式为（）A.简单算术平均数B.加权算术平均数C.简单调和平均数D.加权调和平均数参考答案：D[单项选择题]8、随机变量的观测值中出现次数最多的变量值是该变量的（）A.众数B.中位数C.极值D.均值参考答案：A[单项选择题]9、两个观测值之间如果存在同方向的线性函数关系，则二者的相关关系为（）A.0B.1C.-1D.0.5参考答案：B[单项选择题]10、对于同一数据，所计算出的平均差与标准差相比，通常有（）A.平均差大于标准差B.平均差小于标准差C.平均差等于标准差D.二者关系不定参考答案：B[单项选择题]11、变量x和y的相关系数的符号，取决于（）A.变量x的标准差B.变量y的标准差C.变量x和y两个标准差的乘积D.变量x和y的协方差参考答案：D[单项选择题]12、对于从所考察总体中随机抽取的一个大样本，其样本均值近似服从（）A.正态分布B.x2分布C.t分布D.均匀分布参考答案：A[单项选择题]13、抽样分布是指（）A.抽取样本的总体分布B.样本自身的分布C.样本统计量的分布D.抽样观测变量的分布参考答案：C[单项选择题]14、如果θ^是该参数θ的一致估计，则随着样本容量n的增大，有（）A.θ^的数值接近于总体参数θB.θ^的期望等于总体参数θC.θ^的方差接近于总体参数θD.θ^的方差接近于总体方差σ2参考答案：A[单项选择题]15、在假设检验中，犯第一类错误的概率等于（）A.αB.βC.1－αD.1－β参考答案：A[单项选择题]16、在给定的显著性水平之下，进行假设检验，确定拒绝域的依据是（）A.原假设为真的条件下检验统计量的概率分布B.备择假设为真的条件下检验统计量的概率分布C.观测变量的总体概率分布D.观测变量的样本分布参考答案：A[单项选择题]17、在单因子方差分析中，如果各个因子水平效应相同的原假设为真，则组间平方和SSA（）A.等于0B.等于总平方和C.完全由观测的随机误差引起D.完全由各因子水平的差异引起参考答案：C[单项选择题]18、在方差分析中，所考察的影响观测变量的各个因子都必须（）A.属性化B.数量化C.同质化D.差异化参考答案：A[单项选择题]19、使用最小二乘法估计得出的样本回归直线必然通过点（）A.（0，0）B.（x，0）C.（0，y）D.（x，y）参考答案：D[单项选择题]20、居民家庭人均消费支出的差异随着家庭人均收入的提高而增加，这种现象称为（）A.直线趋势B.曲线趋势C.异方差D.异常数据参考答案：C[单项选择题]21、累计采样所得到的时间序列是（）A.时点序列B.时期序列C.特征序列D.平稳序列参考答案：B更多内容请访问《睦霖题库》微信公众号[单项选择题]22、已知一个时间序列的最初水平和最末水平，要计算各期的平均增长速度，则应采用的计算方法为（）A.算术平均法B.几何平均法C.代数平均法D.调和平均法参考答案：B[单项选择题]23、如果时间序列的环比增长量大致相等，则应采用的趋势模型为（）A.直线趋势模型B.指数曲线趋势模型C.二次曲线趋势模型D.修正指数曲线趋势模型参考答案：A[单项选择题]24、非概率型决策是一种（）A.确定性决策B.非确定性决策C.等可能性决策D.非计算性决策参考答案：B[单项选择题]25、期望损益准则特别适用于（）A.重复性决策B.一次性决策C.确定性决策D.非概率型决策参考答案：A[单项选择题]26、劳动生产率指数是一个（）。

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命题方式：统一命题
佛山科学技术学院2014—2015学年第二学期
《商务统计学》课程期末考试试题E答案
专业班级：13级经济管理1~10班任课老师：辛焕平、贲雪峰、靳娜一、判断题（1分×15=15分）
二、单项选择题（1分×15=15分）
三、多项选择题（2分×10=20分）
四、简答题（6分×2=12分）
1、抽样调查是指从研究的总体中按随机原则抽取部分单位作为样本，进行观察研究，并根据这部分单位的调查结果去推断总体，以达到认识总体的统计调查方法。

特点：（1）按随机原则抽取调查单位；（2）用总体中部分单位的指标数值推断总体指标数值；（3）抽样调查中产生的误差可以事先计算并加以控制。

2、答：时间数列又称动态数列，是将表明社会现象在不同时间发展变化的某种指标数值，按时间先后顺序排列而形成的数列。

其构成要素有两个：（1）现象所属的时间；（2）现象在不同时间上的观察值。

五、综合业务计算题（1小题6分，2、3小题各10分，4小题12分，共38分）
225.11.11100
2.112003
.12600110012002600==
∑∑=++++X
M M
X 甲（元/公斤）
175.11.122002.112003.113002200
12001300==∑∑=++++X
M M
X 乙（元/公斤）甲菜市场白菜平均价格高的原因是高价格的白菜销售量大，低价格的白菜销售量小。

3.
⑴ Kp =
1011q p q p ∑∑×100% = Kp
q p q p 1111∑∑×100% = 750822
×100% = 109.6%
由于价格变化而增加的总产值：
∑1
1q
p －
∑1
0q
p = 822－750 = 72（万元）
⑵
Kpq =
0011q p q p ∑∑×100% = 715
822
×100% = 114.97%
Kq =0010q p q p ∑∑×100%=0
01
1q p Kp
q p ∑∑
×100% = 715750 = 104.9%
⑶ Kpq ＝Kp ×Kq 114.97% = 109.6%×104.9%
∑11q p －∑00q p = (∑11q p －∑
Kp q p 11)＋(∑Kp
q
p 11－∑00q p ) （822－715）= (822－750)＋(750－715)
107 = 35＋72 4. 解：
（1）相关系数：
9574
.087
837*10*
63441*1087
*63605*10)(*)(2
2
2
2
2
2=---=
---
=
∑∑∑∑∑∑∑y y
n x x n y x xy n r
每人月平均销售额与利润率之间是线性正相关关系，高度相关。

（2）
29
.1
63
441
*
10
87
*
63
605
*
10
)
(2
2
2
=
-
-
=
-
-
=
∑
∑
∑∑∑
x
x
n
y
x
xy
n
b
573
.
10
63
*
29
.
1
10
87
=
-
=
-
=
∑∑
n
x
b
n
y
a
利润率对每人月平均销售额的回归直线方程为：y=0.573+1.29x
回归系数b=1.29表示，每人月平均销售额每增加1万元，利润率平均增加1.29%。

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