Recent content by sunone

Hi I found this equation in a machine learning book: "we want to minimize the mean squared error:" $E= \frac{1}{2} \sum_{n=1}^N (y-t)^2$ what I do not understand is the \frac{1}{2} , if it is a mean it should be \frac{1}{N}, why are they restricting to 2? In the text there is no reference to y...

http://img138.imageshack.us/img138/7113/conewithflattip.png Help needed, I need an expression of the figure in the picture, it is like a conic but the tip is not a point but a short 1D segment (it s not a truncated conic), I accept anything ;-) skewed Conics, Sperical Harmonics approx, cubic...