# STATISTICS IN LINGUISTICS

Patrick C. Ryan proto-language at email.msn.com
Sat Feb 27 06:12:13 UTC 1999

```Dear Lars and IEists:

-----Original Message-----
From: Lars Henrik Mathiesen <thorinn at diku.dk>
Date: Friday, February 26, 1999 6:35 PM

[ moderator snip ]

>Pat, there are two types of probability --- observed probability and
>`true' probability. You want to use the former to estimate the latter
>and predict what will happen. You cannot predict based solely on
>observed probability; this is an extremely basic concept.
>
>A correct statement would be that given the observation, the estimated
>probability of the same cause creating the same effect is 100%.
>
>That is, if you use the maximum likelihood estimator, which you will
>find described within the first few chapters of any beginning
>statistics text. The text will also tell you that this estimator is
>totally worthless unless you have a good idea of the possible values
>of the true probability.

Thank you for a lucid explanation of probabilities for all of us.

I agree with everything you have written with the exception that the
situation in historical linguistics is so problematic.

But, why do you not explain in detail why you think it is --- not based on a
priori asssumptions but on analysis of data?

Pat

```