# Why has the following question been determined to be a self-study question which violates self-study policy?

I did not originally ask the question below that was closed, but would appreciate some clarity so I can better understand SE Q&A policies. The generic reason given for closure was that it was off-topic. More specifically, it was stated in comments by whuber that it was a self-study question and was in violation of self-study policies.

Memoryless property: how does $P(X > s + t \mid X > s) = P(X > t), s, t \ge 0$ imply that $F^c(s + t) = F^c(s) F^c(t), s, t \ge 0$?

I am unable to understand why this question was determined to be a self-study question. Please may someone assist me in understanding what features of this question rendered it so, resulting in its closure?

• The question is a complicated request to explain why $a/b=c$ implies $a=bc$ for real numbers $a,b,c.$ As such I recognized it was of no interest here (or even on the Math site) and, casting about for a reason to close it, felt that characterizing it as "self-study" might be the gentlest closure reason to offer. I am open to suggestions of other reasons to close it (there are many valid ones, IMHO).
– whuber Mod
May 4 at 14:24
• @whuber. Thank you for taking the time to assist in this way. I've placed my comment in the box below May 4 at 15:22

Extended comment.

I do not dispute that the content of the question amounts to a simple application of conditional probability. However, you paraphrase the question as if it were a trivial manipulation of real numbers that could be conducted by a 4 year old able to multiply and divide. And perhaps it may seem that way to you as a seasoned statistician.

I think where my concern lies is in how a question being self-study was used as a reason to close a post whose content was deemed too trivial, rather than it being obviously a homework question. The OP took the time to type out in LaTeX the referenced context of the query, rather than it being a screenshot, or other tell-tale signs that they were seeking to turn people into homework machines. They've also made a reasonable attempt to engage with your prompts, even if there has been communication failure in the sense that they were unable to successfully reconstruct the frame of reference from which you trivially see the (non)-problem.

You've said yourself that you were searching for a reason to close on the basis of the question not being sufficiently interesting. If the question is not in any material violation of Q&A policies (i.e. blatant homework) shouldn't it be for the community to decide whether the content of a question is interesting, worthwhile, or even sufficiently trivial to not merit upvotes, not warrant responses, or even to merit a downvote?

And doesn't the fact that another user DoubleOughtNot felt that it was appropriate to take the time to supply a further prompt to the OP run counter to a unilateral determination of what is and is not sufficiently interesting?

I am not trying to make an issue here, I value the work of the moderation team on this Q&A. I just feel that this particular decision (out of hundreds and thousands of spot-on moderator decisions) on the basis of what I have heard so far might not have been the right one. Unless there is something I've missed?

• I appreciate your tactful criticism. It is good to receive such thoughtful reactions: they help us learn and get better. I will point out briefly, though -- not in self-defense but only to suggest there are nuances -- that there is a richer context to this particular post. It includes a history of comparable posts by the OP as well as experience showing that how some users respond is of consequence but not dispositive concerning how to proceed (occasionally, some very highly upvoted and well-crafted posts need to be closed). Finally, the community had its chance and did not vote to reopen.
– whuber Mod
May 4 at 16:01
• @whuber. Thank you for taking the time to address my query. There is no criticism, nor is any of what I have stated meant to be read adversarially. I am just raising what I have perceived to be an issue on the basis of my relative inexperience with this site so far. When I wrote community, I meant the community at large through conventional voting, not the ~0.32% of users with more than 3000+ rep who can vote to re-open or close posts which you are referring to. And I wasn't sure whether this was voted on, or if it was closed unilaterally, so thank you for clarifying. May 4 at 19:41
• However, you have said that there are nuances, a richer context and a history of comparable posts from the OP that I assume warranted closure of this particular question. So if you don't mind my asking, what precisely is the previous pattern of behaviour that has influenced the collective decision to close this particular question? If you feel it might be inappropriate to comment in any specifics, then I would be grateful if you could supply a succinct general statement of what the issue is. May 4 at 19:42
• Lastly, I sincerely appreciate that you have taken the time to address my query, in the sense that resolving moderation queries can be seen to detract from the reason why I guess we all participate in this community - for the purposes of enhancing others' and in the process, our own, statistical understanding. May 4 at 19:56
• @microhaus, "what precisely is the previous pattern of behaviour..." be aware that there can often be more going on that moderators are obliged to keep confidential. May 5 at 11:30
• @gung-ReinstateMonica. Unless I am mistaken, I believe I have addressed that possibility when I wrote "If you feel it might be inappropriate...if you could supply a succinct general statement of what the issue is". I am happy to open a new general question soliciting a general answer if you feel that is more appropriate? May 5 at 12:39
• No, I don't think a new question is necessary. I'm just emphasizing the possibility of limits on what can be said. May 5 at 13:00