# Chapter 9 R Console

When iNZight starts, two windows open: one is the main window in which we work, and a second window is an `R Console`

. R code can be directly typed into this window at the prompt `>`

. The datasets that are imported into iNZight are available at the R console. However note that the R installation that comes with iNZight is different from the one you might have installed yourself with Rstudio, so R packages you may have added will not be available.

This manual does not cover the writing of R code, however some simple calculations may be conveniently done at the R Console.

For example, if we have a confidence interval from iNZight, we can compute the margin of error by simply halving the length of the interval. If the confidence interval has been computed by iNZight as, say,

```
Lower Mean Upper
529.7 584.6 639.5
```

(this is the confidence interval for the mean school size in the `apisrs`

dataset), then we can compute the margin of error in R by typing

`> (639.5-529.7)/2`

at the prompt: i.e. `MOE=(Upper-Lower)/2`

. R responds with the answer:

`[1] 54.9`

Then the SE = MOE/1.96, and RSE=SE/Estimate are given by

```
> 54.9/1.96
[1] 28.0102
```

and

```
> 28.0102/584.6
[1] 0.04791345
```

i.e. an RSE of 4.8%.