江西财经大学试卷统计学C卷英语版

江西财经大学试卷统计学C卷英语版

试卷代码： C 课程学时：48 课程名称：统计学 适用对象：

Ⅰ、SINGLE CHOICE (1′×5＝5′)

1.There are three block products, the percent of wastes just as 1.5% 、2% 、1%,the respective quantities of wastes are 25、30 and 45 pieces. Then what is the average rate of waste.( )

1.5%2%1%33A B 1.5%2%1% C

25304525302%451%1.5%

D

1.5%

2. The retail sales of a company has increased 6% compared with last year, the

average increase in price of each product is 11%, then how much the quantity sold increased or decreased ( )

A.－3％ B.－4.5％ C.4.7％ D.17.7％

3. All the other conditions hold constant. The relation that between desired margin of error (E) and the confidence indicates (

z2) is ( )

A. the wider range of desired margin of error, the lower confidence indicates B. the lower probability, the higher credibility C. the higher probability, the higher precision, D. the lower probability, the lower credibility

4. Put the gold reserves of our country in temporal order by the end of each year in the recent 10 years, the series is ( ).

A. dynamic series B. average series C. time series D. point series

5.In a series of Class interval classification, if frequency of the former group of mode group is equal to the later′s, the mode is ?( ) A the inferior limit of the mode group

B the inferior limit of the mode group and one fourth of the width of the classes C the inferior limit of the mode group and three fourths of the width of the classes D the class mid-value of the mode group

Ⅱ JUDGE (Write “T” for true and “F” for false. 1′×5＝5′) 1. The distribution of population by age is a J –shaped distribution ( )

2. Sampling with replacement and sampling without replacement of the size of samples may be different, but the sampling error is the same ( )

3.From linear function yc= —450＋2.5x，we can get that the relationship between

varies x and y is positive ( )

4. In 2005, the same amount of RMB in a city can only buy 94% of goods compared with 2004, then the price increased by 6% ( )

5. Correlation analysis is a causal relationship analysis ( ) Ⅲ、SIMPLE ANSWER（5′×2=10′）

1. Briefly answer the relations among Correlation coefficient﹑coefficient of regression and discriminate coefficient, formula it

2、How to describe the quantitative characteristics of the population? Please give a list of recapitulative indicators which can describe the characteristics of the population.

Ⅳ、CALCULATION（Total:60′）

1. A MSG(味精)plant that requires each bag of MSG weight no less than 100 grams examine 1% of its products .The result is shown as follows: (demanding the results reserved two decimal places)

(1)Develop a 95.45% confidence interval estimate of the mean weight of these MSG in the sampling with replacement conditions: And determine whether the weight fit to the specifications weight. (10′)

(2)Try to infer the range of rate of qualified products in a 95.45% level of confidence in the condition of sampling with replacement. (8′)

(3)In the same condition, how many samples are needed if the level of confidence is increases to 99.73%? (7′) the 100 and weight of 101-102 102-104 104-106 106 and over total under a bag(gram) quantity5 13 62 17 3 100 （bag）

2. In 1982, the population of China is 10.1 billion, which is amount to 13 billion in 2004. What is the average increase rate of China's population in this period? What is the population in 2006 according to the same rate? (10′)

3 The data of three products produced in Hong Xing Machinery Plant are given as follows: The name of product Unit cost(￥1000) quantity 2004 2005 2004 2005 A(piece) 5 6 400 500 B(case) 8 10 500 600 C(kg) 12 15 150 200 Requirements are: 1. Analyze the change of the gross cost of the three products using index system. 2. Known, Hong Xing Machinery Plant has real profit 3600000 Yuan in 2005; try to calculate the profit rate of cost, if the planed profit rate of cost requires to be raised to 40%, how about the completion of the profit rate of cost? ⅴ、CASE PROBLEM (20′)

Is the educational achievement level of students related to the spending of per pupil?

In many communities this important question is being asked by taxpayers who are being asked by their school districts to increase the amount of tax revenue spend on education The problem is whether increasing spend on education would improve the quality of teaching and improve student′s achievement? The data about the spending per pupil and students’ Comprehensive achievement of the country’s 10 regions’ collected by Federal National Education Assessment Project is shown as follows: state Luyiannuo Florida Delaware New York Texas North Carolina Washington Rhode Island Minnesota George Spending per pupil(＄1000s) 4 3 5 6 4 4 5 5 4 4 Composite scores 591 582 580 600 550 550 611 610 570 0 Questions are: I Describe the population′s characteristics of the students′ achievement in descriptive statistical data.

2. Use regression analysis to investigate the relationship between the spending per pupil and students′ comprehensive achievement.

3. Do you think that the estimated regression equation developed for this data could be used to estimate the composite scores for the states that did not participate in the test?

4. Based on your analysis, do you think that the educational achievement level of students is related to how much the state spends on per pupil?