add higgs example

demo/kaggle-higgs/higgs-pred.R

@@ -0,0 +1,23 @@
+# include xgboost library, must set chdir=TRURE
+source("../../wrapper/xgboost.R", chdir=TRUE)
+
+modelfile <- "higgs.model"
+outfile <- "higgs.pred.csv"
+dtest <- read.csv("data/test.csv", header=TRUE)
+data <- as.matrix(dtest[2:31])
+idx <- dtest[[1]]
+
+xgmat <- xgb.DMatrix(data, missing = -999.0)
+bst <- xgb.Booster(params=list("nthread"=16), modelfile=modelfile)
+ypred <- xgb.predict(bst, xgmat)
+
+rorder <- rank(ypred, ties.method="first")
+
+threshold <- 0.15
+# to be completed
+ntop <- length(rorder) - as.integer(threshold*length(rorder))
+plabel <- ifelse(rorder > ntop, "s", "b")
+outdata <- list("EventId" = idx,
+                "RankOrder" = rorder,
+                "Class" = plabel)
+write.csv(outdata, file = outfile, quote=FALSE, row.names=FALSE)