Figure 1 compares one population of data (orange) with another population (blue). Orange is a control situation (e.g. enzyme activity under standard conditions; distance jumped by grasshoppers) and blue is a test condition (enzyme activity at high pH; distance jumped when confronted by a large spider). On the left are idealised normal distributions of the data as smoothed curves. The upper panel shows populations that seem to be very similar. The lower panel indicates two distinct populations of data. The populations represented in the middle panel are difficult to judge because the data overlap. The mean values are shown as columns, with error bars representing the standard deviation (SD). This emphasises how similar the two datasets are in the upper panels.
Statistics
Your organisation does not have access to this article.
Sign up today to give your students the edge they need to achieve their best grades with subject expertise
Subscribe
