hex.gbm

Class DTree.Split

java.lang.Object

water.Iced

hex.gbm.DTree.Split

All Implemented Interfaces:

java.lang.Cloneable, Freezable

Enclosing class:

DTree

public static class DTree.Split
extends Iced

Constructor Summary

Constructors

Constructor and Description
DTree.Split(int col, int bin, boolean equal, double se0, double se1, long n0, long n1, double p0, double p1)

Method Summary

Methods

Modifier and Type	Method and Description
static java.lang.StringBuilder	ary2str(java.lang.StringBuilder sb, int w, double[] xs)
static java.lang.StringBuilder	ary2str(java.lang.StringBuilder sb, int w, float[] xs)
static java.lang.StringBuilder	ary2str(java.lang.StringBuilder sb, int w, long[] xs)
int	bin()
int	col()
float	improvement() Returns empirical improvement in mean-squared error.
long	rowsLeft()
long	rowsRight()
double	se()
DHistogram[]	split(int way, char nbins, int min_rows, DHistogram[] hs, float splat)
java.lang.String	toString()

Methods inherited from class water.Iced

clone, frozenType, init, newInstance, read, toDocField, write, writeJSON, writeJSONFields

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

DTree.Split

public DTree.Split(int col,
           int bin,
           boolean equal,
           double se0,
           double se1,
           long n0,
           long n1,
           double p0,
           double p1)

Method Detail

se

public final double se()

col

public final int col()

bin

public final int bin()

rowsLeft

public final long rowsLeft()

rowsRight

public final long rowsRight()

improvement

public final float improvement()

Returns empirical improvement in mean-squared error.

Formula for node splitting space into two subregions R1,R2 with predictions y1, y2:

i2(R1,R2) ~ w1*w2 / (w1+w2) * (y1 - y2)^2

For more information see (35), (45) in the paper J. Friedman - Greedy Function Approximation: A Gradient boosting machine

split

public DHistogram[] split(int way,
                 char nbins,
                 int min_rows,
                 DHistogram[] hs,
                 float splat)

ary2str

public static java.lang.StringBuilder ary2str(java.lang.StringBuilder sb,
                              int w,
                              long[] xs)

ary2str

public static java.lang.StringBuilder ary2str(java.lang.StringBuilder sb,
                              int w,
                              float[] xs)

ary2str

public static java.lang.StringBuilder ary2str(java.lang.StringBuilder sb,
                              int w,
                              double[] xs)

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object