Mathematics desk
< January 13	<< Dec \| January \| Feb >>	Current desk >

Welcome to the Wikipedia Mathematics Reference Desk Archives
The page you are currently viewing is a transcluded archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.

January 14

prove that for any event in algebra exists an event in the generated sigma

Let c be an algebra, and g the generated sigma algebra of c. prove that for any delta>0 and for any event E in g, exists an event F in c so p(E\F union F\E)<delta. — Preceding unsigned comment added by 77.126.136.204 (talk) 09:50, 14 January 2020 (UTC)[reply]

Maybe you should clarify what is your function p and what assumption you have (a measure on g? a probability measure?) pm a 10:52, 14 January 2020 (UTC)[reply]

Also,

Please do your own homework.

Welcome to Wikipedia. Your question appears to be a homework question. I apologize if this is a misinterpretation, but it is our aim here not to do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn nearly as much as doing it yourself. Please attempt to solve the problem or answer the question yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know. –Deacon Vorbis (carbon • videos) 13:39, 14 January 2020 (UTC)[reply]

Gotta say, I can't make any sense of the question. What do you mean by "let c be an algebra"? Just a family of subsets of some sample space? What if the sample space has just one point X? If p is a probability measure then the only possible events are the empty set (probability 0) or {X} (probability 1), so the statement you want to prove is false. There has to be more to the question. 2601:648:8202:96B0:0:0:0:DF95 (talk) 21:13, 15 January 2020 (UTC)[reply]

In fact "let c be an algebra" is very clear: it means: "let c be an algebra". However, an algebra is not just a family of subsets. pm a 23:17, 15 January 2020 (UTC)[reply]

Oh ok, I see some clarification at field of sets. I was not familiar with the terminology. Thanks. 2601:648:8202:96B0:0:0:0:DF95 (talk) 07:08, 16 January 2020 (UTC)[reply]