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I'm working on statistics and have seen an equation that has a section like that shown above. $Max(_{y}\epsilon_{nbh(x)}) (a(x,y, t) \cdot b(y,t))$. I am unsure what the '•' means so the whole equation is confusing me.

Both a and b are functions. ngh returns the list of x's


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More information needed. Unless it means multiplication. – GEdgar Feb 5 '13 at 15:48
The whole equation is : Max x Ɛ ngh(x) ((a(x,y,t)⋅b(y,t)). Sorry about the formatting. – user1892574 Feb 5 '13 at 15:53
If $a$ and $b$ are functions with real values, then I think this is multiplication. – GEdgar Feb 5 '13 at 16:03
If $a$ and $b$ are vectors, it's probably the scalar product. – gnometorule Feb 5 '13 at 16:05
I've corrected the formula now. a and b are both functions that return real values; so i guess GEdgar is right. Thanks a lot for the help! – user1892574 Feb 5 '13 at 16:10

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