Standardize numeric variables

Source: R/standardize.R

Standardize the numeric variables in a data frame

standardize(data, mean = 0, sd = 1, include_dummy = FALSE)

Arguments

data

a data frame.
mean

mean of the transformed variables.
sd

standard deviation of the transformed variables.
include_dummy

logical. If TRUE, transform dummy coded (0,1) variables.

Value

a data frame

Details

standardize transforms all the numeric variables in a data frame to have the same mean and standard deviation. By default, this will be a mean of 0 and standard deviation of 1. Character variables and factors are left unchanged. By default, dummy coded variables are also left unchanged. Use include_dummy=TRUE to transform these variables as well.

Examples

head(cars74)

#>                auto  mpg  cyl disp  hp drat    wt  qsec       vs        am
#> 1         Mazda RX4 21.0 cyl6  160 110 3.90 2.620 16.46 V-shaped    manual
#> 2     Mazda RX4 Wag 21.0 cyl6  160 110 3.90 2.875 17.02 V-shaped    manual
#> 3        Datsun 710 22.8 cyl4  108  93 3.85 2.320 18.61 straight    manual
#> 4    Hornet 4 Drive 21.4 cyl6  258 110 3.08 3.215 19.44 straight automatic
#> 5 Hornet Sportabout 18.7 cyl8  360 175 3.15 3.440 17.02 V-shaped automatic
#> 6           Valiant 18.1 cyl6  225 105 2.76 3.460 20.22 straight automatic
#>     gear  carb
#> 1 gears4 carb4
#> 2 gears4 carb4
#> 3 gears4 carb1
#> 4 gears3 carb1
#> 5 gears3 carb2
#> 6 gears3 carb1

cars74_st <- standardize(cars74)
head(cars74_st)

#>                auto        mpg  cyl        disp         hp       drat
#> 1         Mazda RX4  0.1508848 cyl6 -0.57061982 -0.5350928  0.5675137
#> 2     Mazda RX4 Wag  0.1508848 cyl6 -0.57061982 -0.5350928  0.5675137
#> 3        Datsun 710  0.4495434 cyl4 -0.99018209 -0.7830405  0.4739996
#> 4    Hornet 4 Drive  0.2172534 cyl6  0.22009369 -0.5350928 -0.9661175
#> 5 Hornet Sportabout -0.2307345 cyl8  1.04308123  0.4129422 -0.8351978
#> 6           Valiant -0.3302874 cyl6 -0.04616698 -0.6080186 -1.5646078
#>             wt       qsec       vs        am   gear  carb
#> 1 -0.610399567 -0.7771651 V-shaped    manual gears4 carb4
#> 2 -0.349785269 -0.4637808 V-shaped    manual gears4 carb4
#> 3 -0.917004624  0.4260068 straight    manual gears4 carb1
#> 4 -0.002299538  0.8904872 straight automatic gears3 carb1
#> 5  0.227654255 -0.4637808 V-shaped automatic gears3 carb2
#> 6  0.248094592  1.3269868 straight automatic gears3 carb1