Warning message

[Andreas Stolcke]

In message <20060919160016.52311.qmail at web36806.mail.mud.yahoo.com>you wrote:
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> I am developing language models of different order (2 to 5) with Good-Turing 
> discounting and Katz backoff for Smoothing.  I all cases, I have got the foll
> owing warning message:
>     discount coeff 1 is out of range : 6.2135e-17
> 
> I could not get the reason for the warning message. I develop language models
>  5 days ago using the same data and smoothing techniques, but this warning  m
> essage was no there.

Something must have changed.  What was it?  Has the software been updated?

> 
> Could you please tell me the reason behind? Does it affect the quality of my 
> language models?

The warning is issued because discount coefficients (the factors by which
the maximum likelihood estimates are reduced) should be between 0 and 1.
The value you are getting is effectively zero.  It indicates an
anomaly (non-smoothness) in the count-of-count of your data.

--Andreas