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Timeline for Lowest index giving half of the sum

Current License: CC BY-SA 3.0

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Mar 24, 2016 at 7:23 vote accept tsmi
Mar 15, 2016 at 3:36 answer added Anthony Quas timeline score: 1
Mar 15, 2016 at 0:27 comment added Anthony Quas right... sorry. I should have read the question more carefully. Of course knowing one, you know the other.
Mar 14, 2016 at 23:43 comment added Iosif Pinelis Anthony:I think your reasoning is good for the ascending order, but the order is descending. So, the mean should be flipped to about $n-n/\sqrt2$.
Mar 14, 2016 at 22:27 comment added Anthony Quas The variance is of order $n$: if you take the samples up to $1/\sqrt 2$, there are $n/\sqrt 2+O(\sqrt n)$ of them and their sum is $n/4+O(\sqrt n)$. The full sum is $n/2+O(\sqrt n)$. So the way to get the "scale balance point" is to start with the ones up to $1/\sqrt 2$ and then move $O(\sqrt n)$ terms of the biggest terms below $1/\sqrt 2$ or the smallest terms above $1/\sqrt 2$ to the other side to get the two sides to balance.
Mar 14, 2016 at 22:21 comment added Anthony Quas The mean should be close to $n/\sqrt 2$ (if you look at the samples from the $x_i$'s that are below $1/\sqrt 2$, there should be roughly $n/\sqrt 2$ of them and their average value should be $1/(2\sqrt 2)$, so that the sum is roughly $n/4$. On the other hand, the total of all the samples should be close to $n/2$.
Mar 14, 2016 at 22:16 comment added Anthony Quas Quite an interesting question. A somewhat related topic, in case you don't know the name already, is order statistics.
Mar 14, 2016 at 21:36 review First posts
Mar 14, 2016 at 22:30
Mar 14, 2016 at 21:35 history asked tsmi CC BY-SA 3.0