There are two Bayes classifiers. 'TrainClassifier' and 'TestClassifier' are the "old" implementation. These apps take an alpha parameter, but I cannot find where they consult it. Changing it has no effect on the algorithm's performance in the 20 Newsgroups example.
The ASF Emails example script examples/bin/asf-email-examples.sh uses the new Bayes classifier, and changing Alpha does have an effect. On Fri, Dec 30, 2011 at 10:13 AM, Ted Dunning <[email protected]> wrote: > This paper should tell you how alpha works: > http://qwone.com/~jason/papers/sm-thesis.pdf > > On Fri, Dec 30, 2011 at 5:19 AM, Ramprakash Ramamoorthy < > [email protected]> wrote: > >> Dear all, >> >> I see that I can set an alpha(smoothing parameter) to the Naive Bayes >> classifier in apache mahout. The default value of alpha has been set to 1 >> and is an optional parameter. How does this alpha value affect the >> classification results, can I just ignore it and use the default value or >> should I change it for optimal classification? >> >> -- >> With Thanks and Regards, >> Ramprakash Ramamoorthy, >> SASTRA University >> +91 9626975420 >> -- Lance Norskog [email protected]
