Graph description: Figure 15. Normal plots for differences for the raw data, square root transformed data, and log plus one transformed data for the number of attacks of angina

Three graphs, Normal plots headed "Natural", "Square root", and "Log(x+1)".

The plot for natural scale is an upward curve with an oulier low point at the left end.

The plot for the square root scale is similar to the natural scale, but less curved and the outlier is less extreme.

The Normal plot for the log(x+1) scale is close to the straight line for a Normal distribution.

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This page maintained by Martin Bland.
Last updated: 20 January, 2020.