R: ChisqIndependence

hanaml.ChisqIndependence {hana.ml.r}

R Documentation

ChisqIndependence

Description

Perform the chi-squared test of independence to tell whether two variables are independent from each other.

Usage

hanaml.ChisqIndependence(conn.context, data, key = NULL,
                                    observed.data = NULL, correction = NULL)

Arguments

`conn.context`	codeConnectionContext Connection to SAP HANA System
`data`	`DataFrame` Dataset used for training the model.
`key`	`character, optional` Name of the ID column in data that specifies the dependent variable.
`observed.data`	`character, optional` Names of the observed data columns. If not given, it defaults to all non-ID columns.
`correction`	`logical, optional` If TRUE, and the degrees of freedom is 1, apply Yates's correction for continuity. The effect of the correction is to adjust each observed value by 0.5 towards the corresponding expected value. Defaults to FALSE.

Value

The expected count table: DataFrame
structured as follows:
- ID column, with same name and type as data's ID column.
- Expected count columns, named by prepending Expected_ to each observed.data column name, type DOUBLE. There will be as many columns here as there are observed.data columns.
Statistical outputs : DataFrame
including the calculated chi-squared value, degrees of freedom and p-value, structured as follows:
- STAT_NAME, type NVARCHAR(100), name of statistics.
- STAT_VALUE, type DOUBLE, value of statistics.

Examples

## Not run: 
   Input DataFrame for Preprocessing:
> data$collect()
        ID  X1    X2  X3    X4
 0    male  25  23.0  11  14.0
 1  female  41  20.0  18   6.0

   Create chisquare instance:
 > chisquareindependence <- hanaml.ChisqIndependence(conn, data)
   Expected output:
 > chisquareindependence[[1]]$Collect()
       ID  EXPECTED_X1  EXPECTED_X2  EXPECTED_X3  EXPECTED_X4
0    male    30.493671    19.867089    13.398734     9.240506
1  female    35.506329    23.132911    15.601266    10.759494

## End(Not run)

[Package hana.ml.r version 1.0.8 Index]