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May 23, 2017 at 12:37 history edited CommunityBot
replaced http://stackoverflow.com/ with https://stackoverflow.com/
May 4, 2010 at 15:13 answer added Yvan Velenik timeline score: 3
Apr 15, 2010 at 13:04 vote accept Jason S
Mar 29, 2010 at 15:29 answer added Andrea Carbone timeline score: 3
Mar 16, 2010 at 14:05 comment added Jason S Looks like the OP did in fact mean c |m-n| ^ (-alpha) for m != n. Oh well, this is still an interesting question to me. :-)
Mar 15, 2010 at 21:02 answer added Did timeline score: 6
Mar 15, 2010 at 19:15 comment added Jason S Yes, that was pointed out to me... but I am suspicious + wondering if the OP meant alpha ^ |m-n|. Using the c |m-n| ^ (-alpha) formula, correlation is undefined for m=n.
Mar 15, 2010 at 18:09 comment added Douglas Zare By the way, the SO problem is not $\alpha^{|m-n|}$, but $c|m-n|^{-\alpha}$.
Mar 15, 2010 at 17:33 answer added Douglas Zare timeline score: 11
Mar 15, 2010 at 15:56 comment added Jason S ...and I had kind of the same hunch (make a continuous-value process, then use a threshold to produce a binary-value output) but don't quite know how to go about characterizing the output process w/r/t correlation, other than an empirical calculation on the computer.
Mar 15, 2010 at 15:20 comment added Jason S thx for the suggestion... I'm posting this on behalf of someone else (see the link in the 1st sentence) so I do not know the stringency of their requirements. The problem seemed simple enough to state that I felt I could translate into a "proper" problem statement for mathoverflow.
Mar 15, 2010 at 14:59 comment added Alekk you could try to take a process $x(t)$ like an Ornstein-Uhlenbeck, that has a correlation structure that decreases exponentially, and then define $B_n = 1_{x(n) > \alpha}$ where $\alpha$ is a well-chosen threshold - I have not done the computations, but I have the feeling that the correlation between these Bernoulli random variables also decreases exponentially. Do you really need the correlation to be equal to $\alpha^{|m-n|}$ ? Would an exponentially decreasing correlation be enough for your particular purpose ?
Mar 15, 2010 at 14:20 history asked Jason S CC BY-SA 2.5