A graph with two panels, a histogram and a Normal plot, as shown in Answer 4.

In the first panel there is a histogram. The horizontal axis is labelled “Residuals (mm)” and numbered -50, 0, 50, 100. The vertical axis is labelled “Frequency” and numbered 0, 10, 20, 30, 40, 50. There are vertical bars as follows, base then height: -60 to -50, 2; -50 to -40, 1; -40 to -30, 6; -30 to -20, 13; -20 to -10, 34; -10 to 0, 46; 0 to 10, 34; 10 to 20, 23; 20 to 30, 12; 30 to 40, 8; 40 to 50, 2; 50 to 60, 1, 60 to 70, 1, 70 to 80, 0, 80 to 90, 0, 90 to 100, 1.

In the second panel, there is a Normal plot. This is a scatter diagram with points and a line. The horizontal axis is labelled “Inverse Normal” and numbered -50, 0, 50. The vertical axis is labelled “Residuals (mm)” and numbered -50, 0, 50, 100. A straight line goes diagonally from Inverse Normal = -50, Residual = -50, to Inverse Normal = +50, Residual = +50. Each point is represented by a little hollow diamond shape. The points form a curving line, rising progressively more steeply. At the bottom it is just below the straight line. As it rises it goes slightly above the straight line then falls just below the straight line before finally rising above it at the top.

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Last updated: 20 March, 2007.