Understanding and Using Statistics in Psychology takes the fear out of psychological statistics to help students understand why statistics are carried out, how to choose the best test, how to carry out the tests, and then perform the analysis in SPSS. Emphasizing the place of statistical analysis in the process of conducting research, from design to report writing, this accessible and straightforward guide takes a non-technical approach, encouraging the reader to understand why a particular test is being used and what the results mean in the context of a psychological study. The focus is on meaning and understanding rather than numerical calculation.

Chapter 7: Analysing Data from Independent Groups: Categorical Measures

Analysing Data from Independent Groups: Categorical Measures

Analysing data from independent groups: Categorical measures

Key Terms

2-4-6 problem

absolute difference

categorical data

chi-square (χ2) test

confidence intervals

continuity correction

degrees of freedom

Fisher's exact test

nominal data

normal distribution

number needed to harm

number needed to treat

odds ratio

percentage

proportion

psychokinesis

relative risk decrease

Yates' correction

Introduction

This chapter tells you how to analyse independent data that are in the form of categories. We often want to know whether something works or not, whether it is right or wrong and whether someone is hip or minging. There are no half measures; it is one or the other. When we get data of this kind we can ask the same questions we asked in earlier chapters and so estimate the probability of arriving at our ...

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