Graph description: Figure 3. Differences between the observed and predicted values of the outcome variable

This is the same scatter diagram as in the previous two figures, with additional lines.

The horizontal axis shows abdominal circumference in centimetres and is numbered 40, 60, 80, 100, and 120. The vertical axis shows body mass index in kilogrammes per square metre and is numbered 10, 20, 30, and 40. Each of the 86 subjects is shown by a small diamond positioned at that person's body mass index and abdominal circumference.

Higher abdominal circumference is associated with greater body mass index. The relationship is quite close. For abdominal circumference = 50, body mass index ranges from 10 to 20. For abdominal circumference = 110, body mass index ranges from 30 to 40.

A straight line has been drawn through the cloud of points, from abdominal circumference = 50, body mass index = 14, to abdominal circumference = 110, body mass index = 34.

From each point a dashed vertical line has been drawn to meet this straight line.


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This page maintained by Martin Bland.
Last updated 27 July, 2009.