UNIVERSITY OF MALAYA

EXAMINATION FOR THE DEGREE OF MASTER OF APPLIED STATISTICS

ACADEMIC SESSION: 2011/2012 SEMESTER 2

ESGC6121: Survey Techniques and Sampling Design

June 2012 TIME : 2 hours

INSTRUCTIONS TO CANDIDATES:

Answer all questions.

This is an OPEN BOOK examination.

This examination is conducted at the computer lab.

This paper constitutes 50 per cent of the course evaluation.

(This question paper consists of 7 questions on 6 printed pages) and a diskette containing “Empsat”, “Marriage” and “District” data).

ESGC6121/02

Question 1 (5 marks)

You are commissioned to conduct a market survey for a new academic program. Your main respondents are the alumni of the faculty and potential employers.

a) Describe the sampling frame, and an appropriate method of selecting a sample of 1,000 respondents, to ensure sufficient sample size for each group. (3 marks)

b) Describe an appropriate data collection method for the survey, to ensure an acceptable response rate. (2 marks)

Question 2 (5 marks)

Click on the correct answer for each of the following multiple choice questions:

a) What is the first step in the marketing research process?   

  developing a marketing information system

  implementing the research plan

  interpreting data and deciding on type of research

  developing the research plan for collecting information

  defining the problem and research objective

b ) The most important characteristic of the sample in survey research is that it is

 large enough to compare differences between subgroups.

 convenient to access.

 easily observed in naturalistic settings.

 representative of the target population.

ESGC6121/03

c)  Which of the following questions is LEAST useful in a study of attitudes toward smoking?

 Do you smoke or have problems with others who smoke?

 Do you view smoking as unhealthy?

 Are you bothered by secondary smoke?

 Do you think that tobacco companies should be held responsible for smoking-related illnesses?

 d) The cover letter to a questionnaire study should contain all of the following EXCEPT  

 a self-addressed, stamped envelope.

 purpose of the study.

 reasons to respond.

 a list of participants.

e) The major problem with non-respondents in survey research is that

 they tend to be alike in many ways.

 data cannot be analyzed for only part of a sample.

 they may have different opinions than respondents.

 they cannot be found to determine if they are similar to respondents.

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Question 3 (12 marks)

Use “Empsat” data contained in the diskette to answer a-d:

a). Cross-tabulate job satisfaction by i) gender, and ii) decision-making. Perform the appropriate statistical tests. (3 marks)

b) Compare mean income by i) occupation, and ii) gender, and perform appropriate statistical test. . (3 marks)

c) Compare mean income of respondents by occupation and gender. Present the result in a table and a chart. (3 marks)

d) Interpret the results in a-c above. (3 marks)

Question 4 (5 marks)

Use “marriage” data contained in the diskette to answer a-b:

a) Create an index on socio-economic status (as measured by education, job and income). Perform the reliability test. (3 marks)

b) Recode the index obtained in part a) into 3 categories, and give appropriate value labels. (2 marks)

Question 5 (5 marks)

Use “district” data contained in the diskette to answer a-b:

a) select 8 districts, with probability proportional to population size in 1991. (2 marks)

b) estimate the average rate of population growth between 1980 and 1991, based on the 8 selected districts, and place a bound on the error of estimation. (Hint: PPS selection) (3 marks)

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Question 6 (10 marks)

A multinational company wants to conduct an opinion survey on the extension of retirement age. Results of the survey based on stratified random sampling are shown below:

Category of staff Number of staff

Sample size P (proportion in favour of the extension)

Managerial and executive 500 50 0.8

Support staff 2000 200 0.5

a) Estimate the proportion of workers in the company in favor of extending the retirement age, and place a bound on the error of estimation. (3 marks)

b) If the above survey was based on simple random sampling of 250 respondents, and the variance of the estimate is 0.0012, what is the design effect of the stratified random sample? (1 mark)

c) What would be the required sample size if the bound of error is to be reduced to 0.03, using i) proportional allocation, and ii) Neyman allocation? (4 marks)

d). Assuming that half of the workers are in favor of extending the retirement age, what is the required sample size, using simple random sampling, to estimate the proportion, with a bound of error of 0.4. (2 marks)

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Question 7 (8 marks)

7. There are 12 faculties in University Y. A researcher wants to estimate the number of conferences attended by academic staff of the University in 2011. He decided to select 4 faculties, with probability proportional to the number of staff in each faculty, and interview 25 staff from each of the selected faculties.

a) Using the data given in the accompanying table, select the 4 faculties, with systematic sampling in stage 1. Let 120 be the random start. (2 marks)

b) Write down the sampling fraction in the first stage and second stage, and the overall sampling fraction for the four selected faculties. (2 marks)

Faculty Number of academic staff

Stage 1 sampling fraction

Stage 2 sampling fraction

Overall sampling fraction

A 60B 100C 50D 45E 90F 110G 200H 55I 80J 90K 50L 280

c) The survey found that the average number of conferences attended by staff of the selected faculties was 0.8, 0.4. 0.4 and 1.0 respectively. Estimate the average number of conferences attended by academic staff of the university, and place a bound on the error of estimation. (4 marks)

END