Examination for BSc Psychology (PRACTICE PAPER D)

4PAHPRM2 RESEARCH METHODS 2 PRACTICAL EXAMINATION

Section A

The questions in Section A are about the article by Suddendorf (2010).

You are provided with a replication of the experiment from this article in an SPSS data file named: Specimen D Suddendorf Replication.sav

Use the data in this file to answer the questions that follow.

Question A1 [8 marks available]

Suddendorf (2010) reports this analysis on page 494 of their article:

… the difference between 4-year-olds’ (M = 2.32, SD = 1.20) and 3-year-olds’ (M = 1.81, SD = 1.50) number of responses on the yesterday question did not reach significance, t = 1.71; p = .091.

Repeat this analysis for the data that you have been given, and report it.

(a) Table A1. Number of answers given to “Tell me something that you did yesterday” by age-group (report values to two decimal places)

(b) Report the t-test:

(i) The test statistic (to three decimal places): t = __________

(ii) The degrees of freedom df =  __________

(iii) The exact p-value (to three decimal places): p ____________

(Use ‘=’ or ‘<’ as appropriate to your answer.)

(e) Comparing your analysis in this question to the equivalent analysis shown above from Suddendorf (2010); the effect in my analysis is:

Select one answer.

Question A2 [10 marks available]

Suddendorf (2010) analysed the percentage of children who provided at least one answer to “Tell me something that you did yesterday” that was judged as ‘likely to be correct’. This is reported on page 494 of their article:

Less than half of the 3-year-olds generated an answer the parents judged to be likely correct (yesterday: 42%), whereas the majority of 4-year-olds did do so (yesterday: 63%). This age difference … approached significance for the past question (χ²(1, N = 82) = 3.961, p = .076).

Repeat this analysis for the data that you have been given, and report it.

HINT: Use the variables named Age.group and Any.likely.yesterday for this analysis

(b) The test statistic (to two decimal places): = __________

(c) The degrees of freedom df =  __________

(d) The sample size for this analysis N = __________

(e) Report the exact p-value (to three decimal places): p ____________

(Use ‘=’ or ‘<’ as appropriate to your answer.)

(f) Which kind of chi-square test did you use? (Select one answer):

Chi-square goodness-of-fit test / Chi-square test for contingency tables

(g) What do you conclude from this test? (One sentence is sufficient)

Question A3  [10 marks available]

Suddendorf (2010) reports this analysis on page 494 of their article:

As predicted, there was a significant positive correlation between number of likely correct answers on the yesterday and the tomorrow questions (r = .49, p = .001) and this association remained significant when age was partialled out (r = .46, p = .001).

Repeat this analysis for the data that you have been given, and report it.

Report the correlation on this page, and the partial correlation on the page that follows

(a) Obtain and report the correlation (r) between the number of likely correct answers on the yesterday question and the number of likely correct answers on the tomorrow question:

(i) The correlation coefficient (to three decimal places): r = __________

(ii) The degrees of freedom for r: df = __________

(iii) The exact p-value (to three decimal places): p _____________

(Use ‘=’ or ‘<’ as appropriate to your answer.)

(b) When compared to the correlation between these two variables reported by Suddendorf (2010), the correlation that you reported in part (a) above:

Select one answer for each of parts i, ii and iii.

(c) Obtain and report the partial correlation that Suddendorf reports above, by partialling out the variable exact.age from the correlation that you obtained in part (a).

(i) Partial correlation (to three decimal places): r_p = __________

(ii) Degrees of freedom for r_p: df = __________

(iii) Report the exact p-value (to three decimal places): p ____________

(Use ‘=’ or ‘<’ as appropriate to your answer.)

(iv) Which of the following accurately describes what this r_p examines?

Select ‘Yes’ or ‘No’ for each statement.

Question A4 [9 marks available]

(a) Which of the following research terms accurately describe some aspect of the design of Suddendorf (2010)?

Select ‘Yes’ or ‘No’ for each term.

(b) Justify the answers that you gave in part (a) above. The equivalent of one well-written sentence per part (i to iii) will be sufficient for this question.

Section B

The questions in Section B are about the Cups Game Study

Use this data file for Section B: Cups Specimen D.sav

Question B1 [5 marks available]

This question is about methodological hypotheses M1a and M1b:

M1a The proportion of participants who are male will be similar in each condition.

M1b The proportion of participants who are male will not differ significantly between conditions.

(a) The phi correlation (ϕ) provides a standardised measure of effect size for the effect that is described in hypotheses M1a and M1b.

Use SPSS to obtain phi (ϕ) for the association between gender and condition and report it (to three decimal places).

ϕ = __________

(b) The researcher has put forward hypotheses M1a and M1b because they are concerned about the possibility that gender of participant could become a confounding variable in the study. Briefly describe a set of circumstances such that gender would be a confounding variable in the Cups Game Study.

Two or three well-written sentences are sufficient for this question.

Question B2 [15 marks available]

This question is about study prediction P6:

P6 When pooling the data from both conditions together (i.e., not comparing conditions), the average time taken (in seconds) to complete the Cups Game will be significantly lower for participants who used the maximising strategy than for participants who did not use the maximising strategy.

(a) Undertake the appropriate analysis in SPSS and complete the table below, which provides descriptive data relevant to prediction P6.

Table B2. Comparison of participants who used the maximising strategy against those who did not (for all participants in the study, irrespective of condition) for the time taken to complete the Cups Game.

(b) For the average difference described in prediction P6, the researcher considers using a t-test to examine the mean difference. Which kind of t-test is appropriate?

Name of test: ________________________________________________

(c) Prediction P6 can be examined by obtaining the 95% confidence interval (CI) for the mean difference in time taken to complete the Cups Game, which is described in prediction P6.

Use SPSS to obtain that CI, and report it (to two decimal places).

95% CI for the mean difference in time taken to complete the Cups Game between participants who used the maximising strategy and those who did not.

Lower limit: __________ seconds Upper limit: __________ seconds

(d) You should now use a non-parametric test (instead of using a t-test) to examine prediction P6.

(i) Which non-parametric test did you use?

Name of test: ________________________________________________

(ii) Report the test statistic for this test

(to three significant figures): _________  = __________

(iii) Report the exact p-value (to three decimal places): p ____________

(use ‘=’ or ‘<’ as appropriate to your answer.)

(iv) What do you conclude from this test? (One sentence is sufficient)

Question B3 [27 marks available]

For this question, you need only consider the following two predictions:

P3 The average number of times that the red cup is picked will be significantly greater in the deliberation condition than in the control condition.

P4 The proportion of participants using the matching strategy will be significantly lower in the deliberation condition than in the control condition.

Use the data in the file that you have been provided with to write a Results section that would be appropriate for a research report in psychology. Analyse and report only the information that is appropriate and relevant to the two predictions listed above. You should assume that the only variables of interest for your Results section are the ones needed to investigate these two predictions.

You may use tables and graphs where necessary or beneficial. Marks will be awarded for layout, clarity and correct interpretation of the statistical data, and appropriate description of how the data were treated. In order to save space and time, you may use the abbreviations P3 and P4 to refer to the predictions. Any other abbreviations that you use should be defined first. You may assume that parametric statistical tests can be used for analyses that involve measurement data (i.e., for analyses that involve at least one NON-categorical variable). Report a t-test if you are analyzing a mean difference. Exact p-values are preferred to reporting ‘levels’ via the “>” or “<” symbols, except where p < .001.

Write your Results section in the space provided below.