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Ranjini
01-12-2012, 06:44 AM
E= sqrt(<x^2><y^2>-(<x*y>)^2).
In this equation what exactly <x*y>^2 represents? pls help

Dragan
01-12-2012, 08:58 AM
E= sqrt(<x^2><y^2>-(<x*y>)^2).
In this equation what exactly <x*y>^2 represents? pls help

What you have written is not the equation for the product-moment coefficient of correlation. And, why do you use the
notation "< >"?

BGM
01-12-2012, 09:58 AM
The notation < > usually mean inner product of a Hilbert space, which can be defined as the covariance between two random variables. However it has two arguments :P

Dragan
01-12-2012, 10:51 AM
A think a more commonly used notation (for the product moment correlation) is :

\cos \left ( \theta \right )=\frac{X\cdot Y}{\left \| X \right \|\left \| Y \right \|}

where the numerator is the dot product.