add.meta.pred {SIAMCAT} | R Documentation

## Add metadata as predictors

### Description

This function adds metadata to the feature matrix to be later used as predictors

### Usage

    add.meta.pred(siamcat, pred.names,
        std.meta = TRUE,
        feature.type='normalized',
        verbose = 1)

### Arguments

`siamcat` | object of class siamcat-class
`pred.names` | vector of names of the variables within the metadata to be added to the feature matrix as predictors
`std.meta` | boolean, should added metadata features be standardized?, defaults to `TRUE`
`feature.type` | string, on which type of features should the function work? Can be either `"original"`, `"filtered"`, or `"normalized"`. Please only change this paramter if you know what you are doing!
`verbose` | integer, control output: `0` for no output at all, `1` for only information about progress and success, `2` for normal level of information and `3` for full debug information, defaults to `1`

### Details

This functions adds one or several metadata variables to the set of features, so that they can be included for model training.

Usually, this function should be called before train.model.

Numerical meta-variables are added as z-scores to the feature matrix unless specified otherwise.

Please be aware, that non-numerical metadata variables will be converted to numerical values by using `as.numeric()` and could therefore lead to errors. Thus, it makes sense to encode non-numerical metadata variables to numerically before you start the SIAMCAT workflow.

### Value

an object of class siamcat-class with metadata added to the features

### Examples

    data(siamcat_example)

    # Add the Age of the patients as potential predictor
    siamcat_age_added <- add.meta.pred(siamcat_example, pred.names=c('Age'))

    # Add Age and BMI as potential predictors
    # Additionally, prevent standardization of the added features
    siamcat_meta_added <- add.meta.pred(siamcat_example,
        pred.names=c('Age', 'BMI'),
        std.meta=FALSE)

[Package SIAMCAT version 1.6.0 Index]