# Talk:Notation in probability and statistics

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This article should probably have another name ... notation in probability theory ? notation of probability theory ? probability notation ? I don't know.

Anyway, it's just a stub for now, I'm hoping this kind of page can help making the probability articles more understandable. It needs help :) because alone, I'm not sure enough about the right glossary. I studied those things, but long ago and in a different language. Flammifer 30 June 2005 10:49 (UTC)

Hmm, there should also be a Glossary of probability and statistics, instead of / in complement of this page.—Preceding unsigned comment added by Flammifer (talkcontribs)

There is now, thank largely to you! I've just expanded this page to include statistics (and added some more probability too) and renamed (moved) it to "Notation in probability and statistics". Also created redirects from "Statistical notation" and "Notation in statistics". Now to make some more links to here.. --Qwfp (talk) 15:59, 7 February 2008 (UTC)

My textbook ( Artificial intelligence: a modern approach ) uses propositional notation rather than set notation, instead of writing P( union of events A & B ), they write P( A ^ B ); read: probability of boolean variables A and B being true, I think the set notation applies to continuous variables rather than discrete. I haven't gotten that far 65.13.73.143 (talk) 10:52, 3 March 2009 (UTC)

Also we could talk about vectors / joint distributions, conditioning, etc.. but maybe that's better for the Bayes' section 65.13.73.143 (talk) 10:53, 3 March 2009 (UTC)

## Convention for P

The two articles listing notation conventions, namely Table_of_mathematical_symbols and Notation in probability and statistics, seem to disagree about the notation for "Probability": the former mentions a "blackboard" P for display and non-italic P or Pr as alternatives (but not an italic P), while the latter gives only an italic P. This question is prompted by a recent edit by someone which switched from Pr to P in Probability mass function. It would be good for these statements of conventions to be brought into line. Of course there may be some hidden distinction being made in these notations that I haven't spotted. For info, I have placed this message also on the stats-roject talk page Wikipedia_talk:WikiProject_Statistics, but please place discussion here if necessary. Melcombe (talk) 10:17, 11 February 2010 (UTC)

IMHO, if the discussion of a problem starts with defining the probability space, then the symbol for probability should be the probability measure symbol used in the triple. Usually it's P or sometimes ℙ. However when there is no need to define the probability space explicitly, the standard TeX notation is \Pr which renders as upright “Pr”. Non-italic font is consistent with other symbols such as E, Var, Cov.  … stpasha »  22:14, 13 February 2010 (UTC)

Sometimes one wants to use P to refer to a particular probability measure; hence one uses Pr in other contexts. Michael Hardy (talk) 22:23, 13 February 2010 (UTC)