Unit 3 Practice Questions – Solutions 1. The six plays that are chosen (in order) are: 14 03 09 01 04 12 – – – – – – Much Ado About Nothing Taming of the Shrew Julius Caesar Merchant of Venice Midsummer Night’s Dream Romeo & Juliet 2. The four courses that are chosen (in order) are: 05 01 09 13 – – – – History Biology Philosophy French 3. (a) simple random sample (b) voluntary response sample (c) stratified random sample (d) multistage sample (e) convenience sample 4. (a) i. stratified random sample ii. There is no bias in the way this sample is selected. (b) i. convenience sample ii. The bias introduced in a convenience sample is that it selects only individuals who are easiest to reach, and some individuals have no chance of being selected (i.e., those who are not attending the convention). (c) i. census ii. There is no bias in the way this sample is selected. (d) i. multistage sample ii. There is no bias in the way this sample is selected. (e) i. simple random sample ii. There is no bias in the way this sample is selected. (f) i. voluntary response sample ii. The bias introduced in a voluntary response sample is that only individuals who feel strongly about an issue are likely to respond. 5. Note: The following are examples of how the data might be collected using each of the proposed sampling procedures. Other correct answers are possible. (a) The survey is sent to the chief of each reservation, and will be posted on bulletin boards in various locations on the reserve. Residents are asked to respond in writing to the chief’s office, and surveys will then be returned to the government. (b) A government representative randomly selects 500 individuals from a list of all Manitobans living on a reservation. Each of the selected individuals is contacted by telephone to respond to the survey. (c) The survey is sent to every Manitoban living on a reservation. (d) A random sample of six reservations is selected. From each of these selected reservations, a random sample of 50 residents is selected. The survey will be mailed to each selected resident. (e) Government employees distribute the survey at town hall meetings held on reservations across the province. (f) A random sample of 25 residents from each of the province’s reservations is selected. Each of the selected residents will be contacted by telephone. 6. (a) Simple random sampling should result in a good (i.e., representative) sample of students from the three universities. However, since we believe opinions of students at the three universities may differ, it is more appropriate to select a stratified random sample, where each university is a stratum of the population. We can then choose the number of students we would like to survey from each university (which is not possible using simple random sampling). (b) The chance of any student being chosen is calculated in the table below: University Manitoba Winnipeg Brandon Chance of Any Student Sample Size Being Chosen 560 560/28,000 = 0.02 220 220/11,000 = 0.02 60 60/3,000 = 0.02 Using these sample sizes, we see that each student at each university will have a 2% chance of being chosen. (c) Under the sampling scheme in part (b), even though each student has the same chance to be chosen, the resulting sample is not a simple random sample. A simple random sample requires that every possible sample of size n has the same chance of being chosen. This is clearly not the case with our stratified sample. For example, in a simple random sample, it would be possible to select 600 students from the University of Manitoba, 200 students from the University of Winnipeg and 40 students from the University of Brandon. That is not possible under the sampling scheme in part (b), as we are fixing the sample size for each stratum.
This is an online module. This means that all the information you need will be on the MyUnisa site.
Where do you start?
On the MyUnisa site you will find two tabs for EUP1501. One is the main site, EUP1501-Sx-xx, and the second one is your group site EUP1501-Sx-xxxT.
In the main site you will find most of the information you need for the module but you will not be able to post any assignments or post discussions on this site. Prof Goosen (the module leader) will post announcements on this site.
The group site is where you will post your answer to questions, communicate with other students and communicate with your Teaching Assistant.
Read your tutorial letter
After reading the tutorial letter you need to read all the information on the “Home” page of your group site.
The next step would be to check your “Discussions” on your group site. Here your Teaching Assistant will communicate with you and give you extra help and guidance. You can also ask your Teaching Assistant questions here.
This is your “Textbook”. The Learning Units will take you through the module step by step.
What about the assignments and exams?
You will have 9 assignments in this module. It is a lot of work and you will submit assignments almost weekly, but if you plan ahead this is manageable.
Assignments 1,3,5 and 8 are “Discussion Forum” assignments.
By this I mean that you will be posting your answers for these assignments on the discussion forum and it will be graded there (Instructions for assignments can be found in the Learning Units on your EUP1501 group sites).
Assignment 2,4,6 and 7 are practical assignments
These must be completed on a separate site, ITLab. Okay, now it might seem confusing, but it really isn’t. Stay calm, read all the info and be patient. In the Learning Units you will find instructions on how to connect to ITLab. You will receive an e-mail (on your myLife e-mail address) or a sms that will inform you that you are registered for ITLab and will include your username and password to log in.
Assignment 9 is a Blog that you will complete on your group site.
Exam? There is no exam for this module. Jipee! Do not get too excited yet. You need to submit a Portfolio instead of writing an exam.