Skip to main content
4 events
when toggle format what by license comment
Mar 24, 2016 at 18:40 history edited amoeba CC BY-SA 3.0
typos
Mar 24, 2016 at 15:10 comment added probabilityislogic @StasK - l1 would work better, but as it is log-concave would struggle with sparse non-zeros. The ones I mentioned are all log-convex. A close variant to l1 is generalised double pareto - get by taking a mixture of laplace scale parameter (similar to adaptive lasso in ML speak)
Mar 24, 2016 at 15:02 comment added StasK So one way to squish coefficients to be zeroes unless there's really something going on is lasso; in the frequentist version of it, you apply an $l_1$ norm on the sum of the coefficients, and in the Bayesian version of it, you use sharply peaked priors (Laplace $\exp(-|x|)$). So in this case, knowing that you want to have mostly zeroes and a handful of nonzeroes in your output, you modify the prior to correspond to that statement that zero is a much more likely value than any other (vs. the normal prior's statement that values near zero are about as likely as the zero itself).
Mar 24, 2016 at 14:57 history answered probabilityislogic CC BY-SA 3.0