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I would like to ask whether there exists a strictly quasiconcave function that is not quasiconcave. I would say that opposite is true. Thank you in advance for help.

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Doesnt Stricly quasiconcave imply that a function is quasiconcave? –  MITjanitor Mar 1 '13 at 18:42
Please define "quasiconcave" and "strictly quasiconcave". Definitions vary in the literature. –  user53153 Mar 2 '13 at 1:13
But, whatever definitions you choose, I would hope that every strictly quasiconcave function is quasiconcave. Maybe the question has the implication reversed ?? Are you actually looking for a qc function that is not strictly qc ? –  bubba Mar 2 '13 at 4:28
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1 Answer

I fount this statement: Strictly quasiconcave function does not have to be quasiconcave. I would also say that stricly quasiconcave implies that a function is quasiconcave. That is why I ask whether it is possible to find a function which is strictly quasiconcave but it is not quasiconcave.

Thank you.

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Are you the same user who posted the question? If so, please use the flag link to ask for your accounts to be merged. What you posted is not an answer, it should have been a comment or addition to the question. –  user53153 Mar 2 '13 at 15:52
@5pm: Unregistered users cannot flag, and I'm not sure if the account merging powers of the moderators are still working (those should be gone pretty soon, if so). –  Asaf Karagila Mar 2 '13 at 15:58
@Asaf True. What should be done here instead? Unregistered accounts, apparently no access to the older one. –  user53153 Mar 2 '13 at 16:01
Only one thing to do, register one of the accounts and use the merge user form (whose link I don't have handy at the moment). –  Asaf Karagila Mar 2 '13 at 16:02
Here is the link for merge request: math.stackexchange.com/help/user-merge –  user53153 Mar 2 '13 at 16:04
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