1. 1 PS1006 Lecture 5 Results sections - General format Sam Cromie

2. 2 This week: No Seminars No labs Just the exam

3. 3 This week’s exam: Survey research T-tests – independent groups and repeated measures Non-parametric equivalents of t-tests –Mann Whitney U –Wilcoxon signed rank

4. 4 The bow-tie shape of a research report:

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6. 6 IntroductionMethodResultsDiscussion Why we did the study What we did What we found What it means General to Specific Specific to General

7. 7 General background > Specific background > Aims and Hypotheses Introduction

8. 8 Subjects Design Equipment Procedure Method

9. 9 Descriptive Statistics Inferential Statistics Results

10. 10 Explain study results > Fit to other research > Implications Discussion

11. 11 Results in reports - sequence Step 1 - quote descriptive statistics –Graph or table – need to be discriminatory Salient trends identified including those contrary to hypothesis to establish patterns in your data - not just for the sake of it –Clarify the direction and importance of any potential effect A significant t result –does not tell us whether values increased or decreased –Does not tell us if the difference is large or important – just if it is significant –Include measure of variability

12. 12 Step 2 – Inferential statistics state the purpose of the analysis –E.g., “a repeated measures t-test was carried out to determine whether there was any difference between the pre and post-therapy anxiety levels” –helps reader follow the logic of the analysis –helps you formulate the analysis in your own head

13. 13 Should always report –Symbol or name for the statistic used (r, t, T, U) Note statistical symbols should always be italicised –Degrees of freedom or n –Value of test statistic; t = –Whether the probability is greater or less than the alpha value; p.05 –Whether the test was one-tailed or two-tailed A few of the more complicated analyses that you will encounter next year do not have tails e.g., ANOVA. Step 2 – Inferential statistics

14. 14 –This is the job of the discussion –Helps the reader to clearly distinguish what you found from the interpretation you give to it Step 3 – Do not interpret the results

15. 15 Step 4 – Summarise the results at the start of your Discussion –Without reference to results of statistical tests e.g., group A was found to be larger than group B –Indicate whether your hypothesis was supported or rejected

16. 16 Language advice You can assume the reader has knowledge of inferential statistics: –Do not have to mention the null hypothesis –Critical alpha will be assumed to be 0.05. Only mention if you use a more or less conservative value. –You MUST refer to any difference which you investigate as being either statistically significant or non-significant