rescale {arm} R Documentation

## Function for Standardizing by Centering and Dividing by 2 sd's

### Description

This function standardizes a variable by centering and dividing by 2 sd's with exceptions for binary variables.

### Usage

```rescale(x, binary.inputs="center")
```

### Arguments

 `x` a vector `binary.inputs` options for standardizing binary variables, default is `center`; `0/1` keeps original scale; `-0.5,0.5` rescales 0 as -0.5 and 1 as 0.5; `center` substracts the mean; and `full` substracts the mean and divids by 2 sd.

### Value

the standardized vector

### Author(s)

Andrew Gelman gelman@stat.columbia.edu; Yu-Sung Su suyusung@tsinghua.edu.cn

### References

Andrew Gelman. (2008). “Scaling regression inputs by dividing by two standard deviations”. Statistics in Medicine 27: 2865–2873. http://www.stat.columbia.edu/~gelman/research/published/standardizing7.pdf

### See Also

`standardize`

### Examples

```  # Set up the fake data
n <- 100
x <- rnorm (n, 2, 1)
x1 <- rnorm (n)
x1 <- (x1-mean(x1))/(2*sd(x1))   # standardization
x2 <- rbinom (n, 1, .5)
b0 <- 1
b1 <- 1.5
b2 <- 2
y <- rbinom (n, 1, invlogit(b0+b1*x1+b2*x2))
rescale(x, "full")
rescale(y, "center")
```

[Package arm version 1.11-2 Index]