Introduction to Statistics (Psychology)

Introduction

Psychology is an experimental science and studying it requires various types of investigation. Some investigations take the form of experiments where participants have to complete tests under laboratory-style conditions (e.g. the reaction times of a number of individuals are measured under a variety of treatments). Other investigations can be observational. This is where characteristics of different groups of people are compared. (e.g. a comparing the of development of children whose mother smokes with those whose mother does not)

Both types of investigation are subject to variability from many different sources. Statistics are used to analyse the data. They attempt to measure uncertainty and to provide methods for getting as much information as possible from experiments (often computer packages such as SPSS do the majority of the maths for us!).

Statistics can also play an important role in designing experiments by providing techniques for reducing variability and giving advice, for example the choice of sample size to use so that an effect can be detected.

Topics

• Descriptive Statistics (Psychology)
• Data Types (Psychology)
• Displaying Data (Psychology)
• Confidence Intervals (Psychology)

To develop these ideas further see hypothesis testing.