28/08/2020 Assignment 3A - Basics of inference
Assignment 3A - Basics of
inference
Click on a question number to see how your answers were marked and, where
available, full solutions.
Question Number Score
Question 1 4 / 5
Question 2 3 / 4
Question 3 8 / 8
Question 4 12 / 13
Question 5 0 / 4
Total 27 / 34 (79%)
Performance Summary
Exam Name: Assignment 3A - Basics of inference
Session ID: 0744407515
Student's Name: K (Katarina) Djordjevic (011cdd57506642ec949f60ac53aa58da)
Exam Start: Fri Aug 28 2020 15:03:07
Exam Stop: Fri Aug 28 2020 16:07:52
Time Spent: 1:04:44
Question 1
A study compared the rates of serious cardiovascular problems for diabetic patients on
rosiglitazone and pioglitazone treatments. The table below summarizes the results of the
study.
Where appropriate and unless otherwise stated, round your answer to three decimal values.
https://numbas.up.ac.za/run_attempt/46306?resource_link_id=_1985835_1 1/10
, 28/08/2020 Assignment 3A - Basics of inference
Cardiovascular Cardiovascular
problems problems Total
Treatment
Yes No
Rosiglitazone 5143 78332 83475
Pioglitazone 8545 54741 63286
Total 13688 133073 146761
a)
What proportion of all patients had cardiovascular problems?
0.093
Score: 2/2
b)
If the type of treatment and having cardiovascular problems were independent (null
hypothesis), about how many patients in the rosiglitazone group would we expect to
have had cardio-vascular problems?
Expected answer: 7785
7763
Your answer is correct. You were awarded 2 marks.
You scored 2 marks for this part.
Score: 2/2
c)
We can investigate the relationship between outcome and treatment in this study
using a randomization technique. While in reality we would carry out the simulations
required for randomization using statistical so ware, suppose we actually simulate
using index cards. In order to simulate from the null hypothesis, which states that the
outcomes were independent of the treatment, we write whether or not each patient
had a cardiovascular problem on cards, shu led all the cards together, then deal them
https://numbas.up.ac.za/run_attempt/46306?resource_link_id=_1985835_1 2/10
Assignment 3A - Basics of
inference
Click on a question number to see how your answers were marked and, where
available, full solutions.
Question Number Score
Question 1 4 / 5
Question 2 3 / 4
Question 3 8 / 8
Question 4 12 / 13
Question 5 0 / 4
Total 27 / 34 (79%)
Performance Summary
Exam Name: Assignment 3A - Basics of inference
Session ID: 0744407515
Student's Name: K (Katarina) Djordjevic (011cdd57506642ec949f60ac53aa58da)
Exam Start: Fri Aug 28 2020 15:03:07
Exam Stop: Fri Aug 28 2020 16:07:52
Time Spent: 1:04:44
Question 1
A study compared the rates of serious cardiovascular problems for diabetic patients on
rosiglitazone and pioglitazone treatments. The table below summarizes the results of the
study.
Where appropriate and unless otherwise stated, round your answer to three decimal values.
https://numbas.up.ac.za/run_attempt/46306?resource_link_id=_1985835_1 1/10
, 28/08/2020 Assignment 3A - Basics of inference
Cardiovascular Cardiovascular
problems problems Total
Treatment
Yes No
Rosiglitazone 5143 78332 83475
Pioglitazone 8545 54741 63286
Total 13688 133073 146761
a)
What proportion of all patients had cardiovascular problems?
0.093
Score: 2/2
b)
If the type of treatment and having cardiovascular problems were independent (null
hypothesis), about how many patients in the rosiglitazone group would we expect to
have had cardio-vascular problems?
Expected answer: 7785
7763
Your answer is correct. You were awarded 2 marks.
You scored 2 marks for this part.
Score: 2/2
c)
We can investigate the relationship between outcome and treatment in this study
using a randomization technique. While in reality we would carry out the simulations
required for randomization using statistical so ware, suppose we actually simulate
using index cards. In order to simulate from the null hypothesis, which states that the
outcomes were independent of the treatment, we write whether or not each patient
had a cardiovascular problem on cards, shu led all the cards together, then deal them
https://numbas.up.ac.za/run_attempt/46306?resource_link_id=_1985835_1 2/10
