江西财经大学试卷
试卷代码: B 课程学时:48
课程名称:统计学 适用对象:
Ⅰ、SINGLE CHOICE (1′×5=5′)
1. Which of the following is quality index? ( )
A. Gross cost of living index
B. index of staff population
C. index of consumer level of each person
D. quantity sold index
2. What relation can we illustrate from the situation that an approximate constant change in y is associates with a quantitative change in x. ( )
A. Positive linear correlation
B. Negative linear correlation
C. Linear correlation
D. Curvilinear correlation
3. Dividing the survey objects into some groups, then sampling randomly from each group, we called this method.( )
A. equidistant sampling
B. cluster sampling
C. stratified sampling
D. pure random sampling
4. What is the year ′s average increasing rate when the increasing rates of recent three years were 7%、9%、11%?( )
A. 9%
B. 8.8493%
C. 8.9878%
D. 10%
5. Which of the following is standard error of the proportion if the qualified rate of the products is 90 %?( )
A. 10%
B. 90%
C. 9%
D. 30%
Ⅱ、JUDGE (Write “T ” for true and “F ” for false. 1′×5=5′)
1. Range is equal to width of the classes multiply the number of classes at any statistical classification. ( )
2. Margin of error is generally larger than the standard error of the sampling statistics. ( )
3. The formula of Paasche index weight for each item is its base-period quantity. ( )
4. Correlative coefficient is zero implies that there is no Correlation relationship between variables. ( )
5. Whether it is analysis of correlation or analysis of regression, we must determine independent variable and dependent variable. ( )
Ⅲ、SIMPLE ANSWER (5′×2=10′)
1、Briefly describe the relationship among coefficient of correlation 、coefficient of regression and coefficient of discrimination, and express it use formula.
2、Briefly describe the characteristics of Laspeyers index and Paasche index.
Ⅳ、CALCULATION (Total:60′)
A random sample of size 440 acres is selected from a village’s rice, the result of test is that the mean production is 450Kg and sample standard deviation is 80kg.
Requirements are:
①Calculate the sampling standard error of the mean production
②Estimate the mean production of whole village ′s rice at a 95.45% probability.
③If we select the sample from another village, how large a sample should be selected to provide the confidence indicates 2 z
= 2 with a margin of error not exceeding 10kg, assume that the standard error of per acre is 80kg ?(25′)
2、The data of cars′production of an automobile manufacturer in recent years are given as follows:
Year 2000 2001 2002 2003 2004 2005
Quantity 1000 2000 4000 5000 7000 9000
Please work out the parameters a and b according to these data, write out the trend equation by using the least squares method, and explain the economic meaning of b. (15′)
3、The data of the quantity and price in a manufacturer are given as follows:
Please try to analyze the change in the gross value of output from two aspects----relative number and absolute number by factor analysis. (20′)
ⅴ、CASE PROBLEM (20′)
Does age affect unemployment?
Each month the U.S. Bureau of Labor Statistics publishes a variety of unemployment statistic, including the number of individuals who are unemployed and the mean length of time the individuals have been unemployed. For November 2005, the Bureau of Labor Statistics reported that the national mean length of time of unemployment was 14.6 weeks.
The Mayor of New York has requested a study on the status of unemployment in New York area. A sample of 50 unemployed residents of New York included data on the age and the number of weeks without a job. A portion of the data collected in November 2005 is
Questions are:
ⅰ. Describe the population′s characteristics of the unemployed in New York in
descriptive statistical data.
ⅱ. Develop a 95% confidence interval estimate of the mean age of unemployed individuals in New York.
ⅲ. Conduct a hypothesis test to determine the mean duration of unemployment in New York is greater than the national mean duration of 14.6 weeks. Use a 0.05 level of significance. What is your conclusion?
ⅳ. Is there a relationship between the age of an unemployed individual and the number of weeks of unemployment? Explain.。