[Snowball-discuss] probable bug in English stemmer

Andrew Aksyonoff shodan at shodan.ru
Sun Feb 6 23:09:30 GMT 2011

Hello Martin,

Sunday, February 6, 2011, 6:19:44 PM, you wrote:
MP> It is very nice to hear from you again after so many years!
MP> Yes, the snowball-discuss group goes on as ever, though now
MP> I am 66 I'm slowing down somewhat. Richard Boulton of course is
MP> still very young.

Oh wow... time flies like an arrow.  For some reason I thought
you were younger, maybe in your fifties.

MP> In detail, Porter2 stems
MP> exceptionalism to exceptional (step 2)
MP> exceptional to exception (step 3)
MP> exception to except (step 4)
MP> see http://snowball.tartarus.org/algorithms/english/stemmer.html

Many thanks for the clarification.  It's all clear now.  I indeed
did not handle -tional and -ational on Step 3 in my implementation,
and that made me confuse (valid) Step 3 reduction of -tional for
a (buggy) double reduction on Step 4.

Just out of curiosity, I wonder if that change was made after 2001.
That is, whether I made a bug back then, or just now when doing the

MP> Similarly the other words you mention. I hope I've got this right:
MP> like you, I am now a bit rusty on the English stemmer.

I'm getting up to speed again lately. :)

Best regards,
 Andrew                            mailto:shodan at shodan.ru

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