I'm having problem understanding how we choose the weight function. In Andrew Ng's notes, a method for calculating a local weight, a standard choice of weights is given by: What I don't understand is, what exactly is the x here? Apparently
Note that the weights depend on the particular point x at which we’re trying to evaluate x.
But I don't get it.
Take the example of housing prices predicted by number of rooms and size in square feet. So each
x^(i) is a
[roomnum, size] array. So what's in
x? I guess that also should be a
[roomnum, size] array, but what's in it? Is it even a vector? Or is it the target variable? If so, why isn't it marked with y? I don't get it, please help!
How would I choose the x-es? What would they be in an algorithm? Do I have to make guesses for each x? How can I produce a line like this?