This is a scatter diagram showing the difference between velocity of circumferential fibre shortening (VCF) by the two modes, long minus short, on the vertical axis and the average of the VCF measurements by the two modes on the horizontal axis. There is an obvious relationship between the variables: the variability of the differences increases dramatically as VCF increases, so that the points spread out in a horizontal cone. Three horizontal straight lines are shown, marked mean + 2SD, mean, and mean - 2SD. Four points are all outside the outer lines, all towards the right hand side of the graph. The mean line is very close to zero.

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Last updated: 13 January, 2004.