R help - May 2012 - Interpreting Q-Q Plots

My understanding of Q-Q plots is that if the tails of the plotted points
fall above or below the x=y line the distribution of observed/measured
values is under or over dispersed. But, how do I interpret measured values
that are in horizontal lines? The attached plot illustrates this situation.

TIA,

Rich
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Tena koe Rich

Probably highly skewed to the right, with discrete values (perhaps due to the
limitations in the accuracy of the assessment equipment).  But note:

library(fortunes)
fortune('chicken')

HTH .....

Peter Alspach

-----Original Message-----
From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org]
On Behalf Of Rich Shepard
Sent: Tuesday, 15 May 2012 9:53 a.m.
To: r-help at r-project.org
Subject: [R] Interpreting Q-Q Plots

   My understanding of Q-Q plots is that if the tails of the plotted points fall
above or below the x=y line the distribution of observed/measured values is
under or over dispersed. But, how do I interpret measured values that are in
horizontal lines? The attached plot illustrates this situation.

TIA,

Rich

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