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Manual for psimpoll and pscomb
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As discussed under menu N6, there can be a problem
with excluding negative accumulation rates from modelled age-depth sequences.
Each modelled age must be older than the one below it. If, by chance, an age
is taken from the old tail of the one of the age distributions, then next down
must be older still, and this can get increasingly more difficult, especially
where age probability distributions overlap substantially. The default action
is to try 1,000,000 times at each age to obtain a kodelled value older than
the previous value. If this fails, that particular modelled sequence is
abandoned, and the whole sequence re-done. The number of attempts should be as
high as possible, limited by the amount of time available, which is dependent
on the speed of the computer system being used. The default works well for me,
but I recommend trying other values, especially if your sequence of ages has
substantial overlaps. The upper allowed value is the maximum allowed value for
a `long integer', and may be even higher (but not lower) than the value shown
below.
[Allowed range 1-2147483647 (at least)]
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Copyright © 1995-2007 K.D. Bennett
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