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Manual for psimpoll and pscomb

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Menu N: confidence intervals

Menu N6: Include negative accumulation rates in models
Radiocarbon ages and calibrated dates both have a probability distribution, normal in the first case, irregular in the second. Although the dates are known to be in order, because of a stratigraphical relationship, these distributions may (often) overlap. This means that drawing from these distributions can produce modelling sequences of ages that include negative accumulation rates. We can allow this, or we can require that all the modelled series of ages are always positive all the sequence (i.e. each lower modelled date is older than the previous one). Menu N6, here, either allows negative accumulation rates, or prevents them (the default). There can be problems when they are turned off, discussed further in menu N7.

Toggles from `off' to `on'.

Return to menu N.


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Copyright © 1995-2007 K.D. Bennett

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