A scatter diagram.

The horizontal axis shows histology, a categorical variable with three groups: "Benign", "Prostatitis", and "Cancer". The vertical axis shows "PSA" and is numbered 0.1, 1, 10, 100, 1000, and 10000. These numbers are at equally spaced intervals on the scale.

For the Benign group the points form a vertical column from PSA = 0.8 to PSA = 80, with an outlying point at Log PSA = 0.2. For the Prostatitis group the points form a vertical column from PSA = 2 to PSA = 80. For the Cancer group the points form a vertical column from PSA = 1 to PSA = 2000.

The picture is identical to Figure 5, except for the vertical scale.

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This page maintained by Martin Bland.

Last updated: 3 August, 2006.