Advanced spam filters

advanced spam filters
-know spamming ip?
-have you emailed reason before?
-have other people received same message?
-email header consistent
-all caps
-do inline urls point to where they say?
-are you addressed by name?

Digit recognition
-input vector = pixel values
16 x 16

over fitting prevention
-Occam’s razor k?
cross validation

supervised learning
->classification yie{0,1}
->regression yie[0,1] eR

f(x) = w1X + w0
w0 = 3, w1= -1

Linear Regression
Data f(x)=w1x + w0, f(x)=wx+w0
y = f(x)
Loss = Σj(yj-x1xg-w0)2