A histogram of serum cholesterol: a graph like Figure 2, with a different vertical scale.
The horizontal axis is labeled serum cholesterol and numbered 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 and the vertical axis is labeled Frequency density and numbered 0, 5, 10, 15, 20, 25, 30, 35, 40.
There are vertical bars with bases 3.25 to 3.75, 3.75 to 4.25, 4.25 to 4.75, and so on, and with heights 2, 4, 8, 18, 34, 18, 24, 18, 18, 8, 6, 2, 4, 2, 2.
These are double the heights in Figure 2, because they are the frequency per unit cholesterol and the intervals are width one half.
Back to Clinical Biostatistics: Data, frequencies, and distributions.
This page maintained by Martin Bland.
Last updated: 2 August, 2006.