PYC3704/202/1/2021
Tutorial Letter 202/1/2021
PYC3704
Psychological Research: Early Completion
Programme (ECP).
Semester 1
Department of Psychology
• Feedback to Assignment 02
BARCODE
,Dear Student
This study letter contains answers and explanations of the correct options for each question in Assignment
02.
The questions in the two assignments and those at the end of each topic in the Study Guide for PYC3704
should be used as part of your preparation for the exam. We suggest that you try to do the questions from
the Guide and the assignments without looking up the answers. In this way you will see which questions
you can answer, and which ones you cannot answer. This will help you to identify the difficult questions,
and force you to rethink the reasons for the answers. Pay special attention to the explanations we provide,
since this will give you an indication of the weak spots in your own understanding of the material in the
Study Guide. Do not attempt to memorise the questions and their answers. Rather try to understand the
explanations for the correct option in each question. If you did not receive pass marks for the assignments,
you will have to work much harder if you want to pass the exam.
Feedback to Assignment 02 for Semester 1
ASSIGNMENT 02 FEEDBACK ECP
• This is a multiple choice assignment. Choose the one alternative that best completes the
statement or answers the question and fill in the appropriate number on the mark reading sheet.
• The assignment is compulsory in the second semester and will count 10% of your exam mark.
However, if you obtain less than 40% for the exam, this assignment will not contribute to your
exam mark.
• No extension of the closing date can be given as the answers will be provided with feedback
shortly after the closing date.
• Remember to put the correct unique number on the answer sheet if you submit the assignment by
post.
ECP students only Closing date: 19TH June 2021 Unique number: 733362
Question 1
In statistical hypothesis testing, the - - - - - is used to determine the - - - - - which is to be compared to the
chosen - - - - - to make an inference regarding the status of the hypotheses.
1. p-value; level of significance; test statistic
2. test statistic; p-value; level of significance
3. p-value; test statistic; level of significance
4. test statistic; level of significance; p-value
➔ Answer: The correct answer is option 2. To test a hypothesis, you first calculate an appropriate test
statistic, and this is then used to determine the p-value (using statistical tables or a computer program).
After that, this p-value is compared with a level of significance (α), chosen by the researcher, which
represents the maximum risk which the researcher is willing to take that the observed effect is due to
chance and not a reflection of an actual relationship between variables in the population.
2
, PYC3704/202
Question 2
Two samples may be regarded as dependent when - - - - - -.
1. each measurement in one sample is correlated with a measurement in the other sample
2. there is a systematic relationship between the measurements in one sample and the other
3. they were drawn from the same population
4. they are both totally random
➔ Answer: Option 2 is correct and is a definition of dependent samples, where the measurements form
matched pairs. Option 1 is not really valid as a definition of dependence. Correlations are usually
calculated from two measurements (that is, two variables) in the same sample, not from different samples.
If you find a significant relationship, it implies that one type of measurement may be dependent on the
other type of measurement, but it is not really a dependency between two separate samples of data. It is
possible to correlate measurements from two samples if they are paired off in matched pairs of some kind
and finding a significant correlation would then probably imply dependence of some kind. This could imply
that the samples were discovered to be dependent, but it is not how ‘dependent samples’ are defined.
Being drawn from the same population does not imply dependence, so Option 3 is not correct.
Randomness of the samples is not relevant and is in any case likely to imply a lack of dependence, so
Option 4 is also not correct.
Question 3
Suppose H0: = 100 is tested against H1: μ 100 with α = 0.05. If the t-statistic is found to be -3.20 and
the two-tailed p-value is 0.04, what decision regarding the statistical hypothesis can be taken?
1. Reject H0 and accept H1
2. Do not reject H1
2. Reject H1 and accept H0
4. Do not reject H0
➔ Answer: Option 1 is the correct answer. The p-value is 0.04 and α = 0.05, so p-value < α gives a
significant result. The H0 can be rejected in favour of the H1. Note that the p-value provided is two-tailed
and the test is non-directional, so no adjustment of the p-value is needed. If the p-value which was provided
was one-tailed, it would have been necessary to multiply this one-tailed p-value by 2 to get a two-tailed p-
value before comparing it to the level of significance (see p. 81 in the PYC3704 Guide).
Question 4
The following list contains a number of situations where a researcher may consider using a variation of
the t-test:
(a) To compare two group means
(b) To determine whether a relationship exists between two categorical (nominal scale) variables
(c) To compare a group mean with a constant value
(d) To determine whether a relationship exists between two continuous quantitative variables
Two of the statements above are true. Choose the correct set of true statements from the list below:
1. (a) and (c)
2. (a) and (b)
3. (b) and (d)
4. (c) and (d)
➔ Answer: Option 1 is correct. A t-test for a two-groups design can be used to compare two group or
3
Tutorial Letter 202/1/2021
PYC3704
Psychological Research: Early Completion
Programme (ECP).
Semester 1
Department of Psychology
• Feedback to Assignment 02
BARCODE
,Dear Student
This study letter contains answers and explanations of the correct options for each question in Assignment
02.
The questions in the two assignments and those at the end of each topic in the Study Guide for PYC3704
should be used as part of your preparation for the exam. We suggest that you try to do the questions from
the Guide and the assignments without looking up the answers. In this way you will see which questions
you can answer, and which ones you cannot answer. This will help you to identify the difficult questions,
and force you to rethink the reasons for the answers. Pay special attention to the explanations we provide,
since this will give you an indication of the weak spots in your own understanding of the material in the
Study Guide. Do not attempt to memorise the questions and their answers. Rather try to understand the
explanations for the correct option in each question. If you did not receive pass marks for the assignments,
you will have to work much harder if you want to pass the exam.
Feedback to Assignment 02 for Semester 1
ASSIGNMENT 02 FEEDBACK ECP
• This is a multiple choice assignment. Choose the one alternative that best completes the
statement or answers the question and fill in the appropriate number on the mark reading sheet.
• The assignment is compulsory in the second semester and will count 10% of your exam mark.
However, if you obtain less than 40% for the exam, this assignment will not contribute to your
exam mark.
• No extension of the closing date can be given as the answers will be provided with feedback
shortly after the closing date.
• Remember to put the correct unique number on the answer sheet if you submit the assignment by
post.
ECP students only Closing date: 19TH June 2021 Unique number: 733362
Question 1
In statistical hypothesis testing, the - - - - - is used to determine the - - - - - which is to be compared to the
chosen - - - - - to make an inference regarding the status of the hypotheses.
1. p-value; level of significance; test statistic
2. test statistic; p-value; level of significance
3. p-value; test statistic; level of significance
4. test statistic; level of significance; p-value
➔ Answer: The correct answer is option 2. To test a hypothesis, you first calculate an appropriate test
statistic, and this is then used to determine the p-value (using statistical tables or a computer program).
After that, this p-value is compared with a level of significance (α), chosen by the researcher, which
represents the maximum risk which the researcher is willing to take that the observed effect is due to
chance and not a reflection of an actual relationship between variables in the population.
2
, PYC3704/202
Question 2
Two samples may be regarded as dependent when - - - - - -.
1. each measurement in one sample is correlated with a measurement in the other sample
2. there is a systematic relationship between the measurements in one sample and the other
3. they were drawn from the same population
4. they are both totally random
➔ Answer: Option 2 is correct and is a definition of dependent samples, where the measurements form
matched pairs. Option 1 is not really valid as a definition of dependence. Correlations are usually
calculated from two measurements (that is, two variables) in the same sample, not from different samples.
If you find a significant relationship, it implies that one type of measurement may be dependent on the
other type of measurement, but it is not really a dependency between two separate samples of data. It is
possible to correlate measurements from two samples if they are paired off in matched pairs of some kind
and finding a significant correlation would then probably imply dependence of some kind. This could imply
that the samples were discovered to be dependent, but it is not how ‘dependent samples’ are defined.
Being drawn from the same population does not imply dependence, so Option 3 is not correct.
Randomness of the samples is not relevant and is in any case likely to imply a lack of dependence, so
Option 4 is also not correct.
Question 3
Suppose H0: = 100 is tested against H1: μ 100 with α = 0.05. If the t-statistic is found to be -3.20 and
the two-tailed p-value is 0.04, what decision regarding the statistical hypothesis can be taken?
1. Reject H0 and accept H1
2. Do not reject H1
2. Reject H1 and accept H0
4. Do not reject H0
➔ Answer: Option 1 is the correct answer. The p-value is 0.04 and α = 0.05, so p-value < α gives a
significant result. The H0 can be rejected in favour of the H1. Note that the p-value provided is two-tailed
and the test is non-directional, so no adjustment of the p-value is needed. If the p-value which was provided
was one-tailed, it would have been necessary to multiply this one-tailed p-value by 2 to get a two-tailed p-
value before comparing it to the level of significance (see p. 81 in the PYC3704 Guide).
Question 4
The following list contains a number of situations where a researcher may consider using a variation of
the t-test:
(a) To compare two group means
(b) To determine whether a relationship exists between two categorical (nominal scale) variables
(c) To compare a group mean with a constant value
(d) To determine whether a relationship exists between two continuous quantitative variables
Two of the statements above are true. Choose the correct set of true statements from the list below:
1. (a) and (c)
2. (a) and (b)
3. (b) and (d)
4. (c) and (d)
➔ Answer: Option 1 is correct. A t-test for a two-groups design can be used to compare two group or
3
