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## #1 Help Me ! » contour » 2010-09-20 12:58:43

qlinsey
Replies: 1

Hi, dear all,

who can tell me the contour of this function :f(x,y)=xlg(x/y)+(1-x)lg((1-x)/(1-y))..can plot out ..?

thanks a lot
linsey

## #2 Re: Help Me ! » help me about the theoretical part » 2010-09-20 00:06:26

hi, Dear all,

who are calculs specialist? who help me figure out the theoretical part...? very appreciated if can give me a hand.  I really want to understand that part .... I send email to all the authors who wrote this paper , but no one replied to me. Seems the theory is very easy ...or they don't have time ..?

thanks
linsey

## #3 Re: Help Me ! » help me about the theoretical part » 2010-09-20 00:02:34

Hi,

Yes, The guy is from Yahoo! I even sent email to him , but no response. My supervisor discussed with me for 1 hour , but still can't figure out and he asked me read more.  So how did you continue your research work or your stuff without understanding that part. Just use the very good approximation value hi= p/4 in (4.2) (sorry , p is not correct, but i couldn't type in that value 180° =3.1415926)...?

thanks
linsey

## #4 Re: Help Me ! » help me about the theoretical part » 2010-09-19 23:10:42

This paper --spatial scan statistics: approximation and performance study (authors: Deepal Agarwal, Andrew McGregor, etc.) , can be downloaded on website from google searching....

best regards
linsey

## #5 Help Me ! » help me about the theoretical part » 2010-09-19 23:08:37

qlinsey
Replies: 8

HI, dear all,

Currently I am reading the paper "spatial scan statistics: approximation and performance study " and confused with section 4.1. I read many times , but still cannot get the meaning how the formula of (4.2) come from and why hi=p /4 can give a very good approximation for the convex function? could you guide me which mathematic theoretic background I should read or...how to understand this part?   Futhermore, in fact,I cannot relate lemma 4.2 to the part of explaination using Figure 3 (a),(b).

Hope can helpe me to figure out !

thanks !
linsey