For "importance" it's probably best to stick with absolute values of coefficients, instead of value of the penalty parameter for which the coefficients changed to non-zero. Friedman skipped a lot of details on his rule ensemble in that talk, due to time constraint. In his implementation he was using his own algorithm, PathSeeker, for which paper and software are available on his web page. PathSeeker is a different generalization of LASSO than LAR. HTH, Andy From: zubin> > Attended JSM last week and Friedman mentioned the use of > LASSO for variable selection (he uses it for rules > ensembles). I am an econometrician and not familiar with, i > started running the examples in > R this week and you get to the plots section of the LARS package. > Plots of beta/max(beta) vs standardized coefficients. How > does one interpret them? u see plots of each variable > converging to zero at different times - its pretty cool - but > can i use this for variable importance? > > for variable selection - i have a group of correlated > variables that we need to determine importance in predicting > change of a Y variable. > > -zubin > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > >
Hello! I am using the deldir package to visualize my data, pretty neat. However, i need to fill the colors using polycol =, fill with colors like a heatmap - more of a gradient fill. The only colors i get are very blocky - how do i assign the correct colors for a gradient, even a grayscale? i tried the chart of R colors, using 200 numbers for grayscale but not getting them. The polycol = colors the cells in the tesselation with the value a specific vector for color. Code below: library(deldir) set.seed(1) #generate data y <- runif(20) x <- runif(20) z <- rep((2:4),2) #run voronoi from deldir package ddd <- deldir(x,y) ttt <- tile.list(ddd) plot.deldir(ddd,wlines="tess") #play with colors plot(ttt,polycol=z,close=TRUE)