SAMPLING

Sampling



Sampling

TASK 1

Your task is to establish if the sample was representative of the overall WMU student population by gender and hometown. To answer this question you should perform some very simple calculations and use WMU 2006-07enrollment information below.

Sample Representation

Gender

Sample Size

Proportion

Hometown

Sample Size

Proportion

Male

11

38%

Michigan

27

93%

Female

18

62%

Out-of-State

2

7%

 

 

 

International

0

0%

Total

29

100%

 

29

100%

Sample Comparison with WMU 2006-07 Enrollment

Gender

Number of students

% of Total

Sample Percentage

Difference

Representation

Men

11,765

47%

38%

-9%

Under-represented

Women

13,076

53%

62%

9%

Over-represented

Hometown

 

Michigan

22,279

90%

93%

3%

Over-represented

Out-of-State

1,587

6%

7%

1%

Over-represented

International

975

4%

0%

-4%

Under-represented

Total students

24,841

100%

 

 

 

Question: Conclude if females and males are over- or under-represented in our class. If yes, by what percent?

(a) Males are under-represented by 9% in the sample.

(b) Females are over-represented by 9% in the sample.

Question: Conclude if three categories of hometown are over- or under-represented in our class. If yes, by what percent?

(a)Michigan hometown is over-represented by 3% in the sample.

(b)Out-of-state is over-represented by 1% in the sample.

(c)International is under-represented by 4% in the sample

TASK 2 (A - C)

At the last page of this assignment is a complete list of students in one of my previous Soc 282 classes. Use it as your Sampling Frame. Your task is to put together three different samples of our students using probability sampling methods:

(a) Simple random sample;

(b) Systematic random sample, and

(c) Proportionate stratified random sample.

Task 2 A

2 a. Using the Table of Random Numbers, select a simple random sample of 10 students from the sampling frame.

First, take the table of random numbers provided below and select your sample. As you select your sample, you will move through the list of random numbers in the random number table. Second, in column 2 record the five-digit numbers from the table of random numbers that you will use to select your individuals and highlight those particular digits that will be your selection numbers. Third, in column 3 write the names of the students selected to your sample

Simple Random Sample

In the below presented list, simple random sampling technique has been used. In the below presented case, all student names had equal probability of being selected at random.

1

Sample element number

2

Random number used

3

Names selected

1

38730

Sharp, Staci M.

2

40643

Wimberly, Amy L.

3

36408

Finley, Chad A.

4

96619

McGrath, Jamie A.

5

69420

Mickels, Megan M.

6

20941

Williams, Kathryn L.

7

87704

Dahlstrom, Luke N.

8

03803

Crampton, Matthew J.

9

20035

Upchurch, Ashley M.

10

91432

Slagter, Andrew J.

Answer the following questions:

1. How many digits from five did you use to select names?

Answer: Last two digits

2. Is there the right way of moving within the table of random numbers?

(a)down the page

(b)bottom up

(c)sideways

(d)diagonally

(e)all of the above

Answer: Down the page

Task 2 B

Using the same student sample frame, select a systematic random sample of 13 students. Fill in the requested information:

1.What sampling interval did you use?

Answer: Every 4th student name was used as a sampling interval.

2. Student name you started from __________

Answer: Carlson, Fonda J.

3. Explain how you selected the student from the frame to start your systematic selection.

In the below presented list, systematic random sample technique has been used. Selection of every 3rd name from the list creates changes in the probability of selection of every participant. First person selection in the data had simple random sampling; however, equal probability of selection is replaced ...