#### Install R

Restriktor is implemented as an R package. This means that before installing
restriktor, you should have installed a recent version (>= 3.0.0) of R. You can
download the latest version of R from the
R-project website.

#### Install Graphical User Interface (GUI)

R is a command line driven program. This means that it does not have a graphical
user interface (GUI). Luckily, there are many good GUI's to make life easier, for
example Rstudio, R Commander
and RKWard.

#### Install restriktor

Once you have installed R, the next step is to install restriktor. This can be
done by typing in R:

```
install.packages("restriktor", dependencies = TRUE)
```

To check if the installation was successful, you can load the restriktor package
and try for example:

```
## load the restriktor library
library(restriktor)
## construct constraint syntax based on the factor level names
constraints <- 'GroupActive < GroupPassive
GroupPassive < GroupControl
GroupControl < GroupNo'
## fit the unrestricted linear model, where "Age" is the response
## variable and "Group" a factor with four treatment groups.
fit.ANOVA <- lm(Age ~ -1 + Group, data = ZelazoKolb1972)
## fit the restricted model
restr.ANOVA <- restriktor(fit.ANOVA, constraints = constraints)
## summary of the restricted parameter estimates
summary(restr.ANOVA)
```

If you can see the output, everything is set up and ready.

#### Getting Started

Now that you have installed restriktor, read the restriktor tutorial
to get you started.