Hi Everyone,

I've just finished my write-up for optimizing the languages that could eventually be used for language detection on French Wikipedia. (Spanish, Italian, and German are still to come.)

The full write-up gives details on corpus creation and clean up, performance stats, and more.

Briefly, about 15% of "low performing" queries (those with < 3 results) are easily filtered junk, and 65% of the remainder are not in an identifiable language (e.g., names, acronyms, more junk, etc.).

Based on a sample of 682 poor-performing queries on frwiki that are in some language, about 70% are in French, 10-15% are in English, about 7-12% are in Arabic, fewer than 3% are in Portuguese, German, and Spanish, and there are a handful of other languages present.

Because of the relatively low percentage of low-performing queries that are relevant, we will still need to do an A/B test before discussing deploying this to frwiki. An A/B test on enwiki in in the works at the moment.

The optimal settings for frwiki, based on these experiments, would be to use the TextCat query-based models for French, English, Arabic, Russian, Chinese, Armenian, Thai, Greek, Hebrew, Korean (fr, en, ar, ru, zh, th, el, hy, he, ko), using the default 3000-ngram models.

—Trey