Title C8511 Research Skills One Sample Paper With Answers Statistical Hypothesis Testing Null Hypothesis Correlation And Dependence Statistical Analysis 254.4 KB 21
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C8511 Research Skills in Psychology

SECTION 1: BASIC CONCEPTS

In this section, a concept is given together with five alternative definitions, only one
of which is correct. Indicate which of the definitions is correct by writing the
appropriate letter (a, b, c, d or e) in the table on page 15 at the end of the exam
paper (2 marks per question).

1. The mean is:
(a) a summary of some data estimated by adding all the numbers, and dividing

by the number of numbers minus one.
(b) a summary of the data that is a measure of the population rather

than the sample.
(b) a summary of some data that is always half way between the

maximum and minimum value of the data.
(c) a summary of the data in terms of the most common value of the

data.
(c) none of the above.

2. If data show "homogeneity of variance", it means that:
(a) they must be analysed with a Chi-Square test.
(b) scores in each group or condition show comparable amounts of

variance.
(c) the data are normally distributed.
(d) they have been measured on an interval or ratio scale.
(e) none of the above.

3. The variance is always:

(a) a measure of how noisy the data are, relative to a control.
(b) the square of the standard deviation.
(c) a measure of how many mistakes the subjects made.
(d) a measure that changes if you add a constant to all of the data.
(e) none of the above.

4. The null hypothesis is always:

(a) proved to be incorrect by a significant result.
(b) the hypothesis you do not believe before an experiment.
(c) the simplest explanation for the data collected.
(d) shown to be highly unlikely by a significant result.
(e) none of the above.

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C8511 Research Skills in Psychology

SECTION 3: WHICH TEST?

In this section you will be given a brief description of a study and some data; you
have to choose the appropriate test. Unless stated otherwise, assume the data are
normally distributed and show homogeneity of variance. There are 10 questions,
each worth 2 marks. For each question write the letter corresponding to the correct
test (i.e. A for Wilcoxon, B for Friedman, etc.) in the table on page 15 at the end of
this exam paper. (Do not write the name of the test itself in the table: if you do so, it
will not be counted as an answer).

A. Wilcoxon. E. Spearman’s rho.
B. Friedman. F. Pearson’s r.
C. Mann-Whitney. G. Chi-Squared.
D. Kruskal-Wallis.

1. A researcher is interested in whether there is a relationship between daily
temperature and the amount of time that students study. She measures the
temperature each day for six months, and the mean number of hours spent in the
library by a group of students. What test is required to test the hypothesis that
study time is related to temperature? F

2. A study was performed to examine the effects of allergies on mood. One group
of participants were allergy-free; another group suffered from severe hayfever; a
third group suffered from eczema; and a fourth group had gluten intolerance. A
therapist rated the mood of each participant on a 100-point scale. Which statistical
test should the researchers use to see if allergies affect mood? D

3. A study was performed to investigate the effects of alcohol on people's
impulsivity. Three groups of participants were compared. One group had water; one
group had 1 pint of beer; and the third group had one pint of vodka. Each subject's
impulsivity was assessed by a questionnaire that yielded a score out of 50. Which
statistical test should the researchers use to test if alcohol affects impulsivity? D

4. A researcher is interested in comparing the effectiveness of four different scuba
diving courses. He assembles a boat-full of divers (twenty from each course), and
takes them to a nearby barrier reef. Each diver makes one dive, in which he
attempts to stay safely below the water for 40 minutes. The researcher then
measures the number of divers from each course who successfully return to the
surface. Which test should the researcher use in order to see if there is a
significant difference between the effectiveness of the different training courses? G

5. In response to claims that A-levels are easier now than they were 20 years ago,
a group of current sixth-formers are given two English exams, one a copy of the
1980 A-level paper, and the other a copy of the 2005 A-level paper. Each student
provides a mark for each exam, out of 100. Their scores for the 1980 paper are
heavily skewed. Which statistical test should be used to test the hypothesis that
English exams used to be harder than they are nowadays? A

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C8511 Research Skills in Psychology

6. Researchers wants to find out if there is a relationship between length of
service in academia and levels of obsession. The obsession level of each of fifty
lecturers was measured by questionnaire. The length of time that each lecturer
had been in the university was also recorded. After collecting these data, it was
found that the scores were somewhat skewed towards the "highly obsessive"
end of the scale. Which test should be used to measure the strength of the
relationship between obsession and length of time in employment? E

7. Anecdotal evidence suggests that many comedians' choice of career can be
traced to their childhood experiences of using comedy in order to avoid being
bullied at school. 200 comedians and 300 member of the public were interviewed
and asked whether or not this use of comedy was true of them personally. What
test should be used to test the hypothesis that bullying encourages children to
follow a career in comedy? G

8. Ten children are each given four different toys to play with, and are asked to
rate each toy in terms of how much they liked it. Which test would you use to
assess whether the four toys are liked equally? B

9. Three hundred bird watchers are given the choice between a telescope and a
pair of cheap binoculars. 182 prefer the telescope. Which test would you use to
determine whether or not this is a statistically significant difference in preference?
G

6. 200 drivers' performance was rated by a professional driving instructor
under three conditions: while they drove for 30 minutes without distraction, while
they drove for 30 minutes using a hands-free mobile phone, and while they drove
for 30 minutes and listened to the radio. What test would you use to determine
whether distraction affected driving performance? B

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