统计学试卷(国际学院-英文)(共4页)

1、精选优质文档-倾情为你奉上江西财经大学试卷 试卷代码： A 课程学时：48 课程名称：统计学 适用对象： 1. Single selection（1 point per question, 10 points total）1Which option below is a continuous indicator? （ C ）A、Number of employees B、Number of machines C、Gross industrial output value D、Number of workshops2Which ratio below represents the largest

2、 variance?（ B ）。A、0.7 B、0.5 C、0.1 D、0.43Assuming a population with normal distribution. In order to estimate the interval of its mean value, which statistic should be used if only a small sample is available? （ C ）A、Normal statistic B、2 statistic C、t statistic D、F statistic4If all observed data valu

3、es fall on the regression line, then the correlation between these two variables is（ C ）。A、1 B、-1 C、+1 or -1 D、05Sampling standard variance (eg. ) shows the （ C ） between sample indicator and population indicatorA、Real errorB、Absolute value of real errorC、Average level of errorD、Possible level of er

4、ror6If we know the of a linear regression is 0.64, then the residual sum of squares occupies a proportion of （ A ） in the total sum of squares.A、0.36 B、0.8 C、0.6 D、0.27Assuming is twice as much as , and is 1.2 times as much as . Then the correlation coefficient should be （ D ）. A、Not calculable B、0.

5、6 C、 D、8Estimating the percentage of germination based on a limited number of germination tests is a method of （ B ）A、Comprehensive analysisB、Inductive concludingC、Mass analysisD、Statistical grouping9If we try to transform a general index into weighted arithmetical mean form， the weight should be （

6、B ）A、The numerator of the general indexB、The denominator of the general indexC、A fixed weightD、Based on the particular problem10The correlation coefficient r and the regression coefficient b should be （ A ）A、Of the same sign B、Of the different sign C、Mostly of the same sign D、Sometimes of the differ

7、ent sign2. True or False （ 1 point per question, mark “T” behind the true statements, “F” behind the false statements. 10 points total）1In real statistical applications, when calculating price index, quantity indicators of the base period are often used as the metric unification factor. （ F ）2Just l

8、ike correlation analysis, regression analysis analyzes two random variables. （ F ）3The general index（indicator） calculated based on the unit（element）variables representing a population numerical property is a random variable （F）4When the volume of sample increases, if the estimated value approaches

9、the real variable being estimated, we can say this estimated value has the property of consistency.（ T ）5The relationships between variables can be summarized into correlating relationship and functional relationship.（ T ）6Population index has two calculation method: general index and mean value ind

10、ex.（ T ）7If the hypothesis being tested is H0：0, a left one-side test should be used.（T）8Both the regression coefficient b and the correlation coefficient r can describe the closeness of the relationship between two phenomena.（ F ）9If the correlation coefficient is 0, then the two variables has no c

11、orrelation. （ F ）。10If the sales volume of items increased by 5%, meanwhile the price decreased by 5%, the sales value stays the same. （ F ）3. Question and answers（5 Points ×2=10 Points ）1Describe briefly the principles for making general index.2Describe briefly the central limit theorem.4. Cal

12、culation（45 Points）1A company is examining a shipment of packaged goods that is about to be sent. 100 packages are sampled. On average, there are 99 items in every package with the standard variance of 5. Try estimate the interval of the mean number of items in every package with the confidence leve

13、l of 95.45%. If the allowed error margin is reduced to a half of before, while all other variables stay unchanged, how many packages need to be sampled? If we know the pass rate of the packages in the sample is 90%, then estimate the interval for the pass rate of the whole shipment with the same con

14、fidence level as before. （16 Points）。2A company exports packaged tea abroad. The package weight is specified to be 500g. Bases on past experience, we know the standard deviation of the package weight is 5g. Now the company is examining a shipment before its shipped. 100 packages are sampled, and the

15、 average weight is 502g. If the package weights are normal distributed, then does this shipment fall within the specification (significance level is 0.05)? Elaborate what kind of mistake can be made during this judging process. （14 Points）。3The exporting price and volume of 3 products are listed bel

16、ow:ProductExport volumeExport Price（USD）Base PeriodReport PeriodBase PeriodReport PeriodA（Piece）15001800240200B（Meter）210020008690C（Ton）32003800140165Question: Using the index system, analyze the impacts that the changes of export volume and price have caused on the export value, with both the relat

17、ive numbers and the absolute numbers. （15 Points ）。5. Case Study（25 Points ）A company makes a certain kind of goods. The data for product volume and unit cost as listed below:Month123456Volume（Piece）234345Unit cost（10,000 yuan）737271736968Question：（1）Make a scatter diagram to find out the direction and type of correlation between the two variabl