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Here I found about Geometric median. But i am still unable to calculate Geometric median of some points (x, y). Can some body please calculate Geometric median by giving an example? For an example, let say i have six points a(-3,0), b(-2,0), c(-1,0), d(0,0), e(10,0), f(50,0). So what is the Geometric median of these points? Thank you.

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Did you try out the computation algorithm described in the wikipedia article you referred to? –  Harald Hanche-Olsen Apr 15 '12 at 8:00
    
@HaraldHanche-Olsen: Here is the Definition of Geometric median. I didn't get the formula. –  Ravi Joshi Apr 15 '12 at 8:16
    
Harald is pointing out that the Computation paragraph of the Wikipedia essay seems to answer your question. What part of the discussion there are you finding difficult? –  Gerry Myerson Apr 15 '12 at 9:08
    
@GerryMyerson: Okay.... actually i was concentrating on Definition paragraph. –  Ravi Joshi Apr 15 '12 at 9:12
    
Huh? Your question is about calculating the geometric median, not about defining it. So now I'm confused - what is it you really want to know? When you decide, maybe you could edit your question so it accords with what you actually want to ask. –  Gerry Myerson Apr 15 '12 at 10:13
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1 Answer

What I do (crude but still helpful): Find median of data along X axis, find median of data along Y axis. This gives me coordination of "quite good estimatiom" of true geometric median. You can do the procedure to obtain means, however with simulations I found that using median is usually more correct.

I know this is very crude method, hope it helped you.

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