Interpreting Standard Deviation

• The standard deviation tells us how far scores deviate away from the mean. The larger the standard deviation, the greater the dispersion or spread within a set of data. If we are talking about a particular condition within an experiment, a large standard deviation suggests that not all participants were affected by the IV in the same way because the data is quite widely spread. It may be there are a few anomalous results.
• A low standard deviation suggests data is tightly clustered around the mean, which implies all participants respond in a similar way.