```
proc glm;
class drug disease;=drug disease drug*disease;
model y run;
```

# linear-models

**Getting Started**

To demonstrate the various types of sums of squares, we’ll create a data frame called `df_disease`

taken from the SAS documentation.

### The Model

For this example, we’re testing for a significant difference in `stem_length`

using ANOVA.

### Sums of Squares Tables

SAS has four types of sums of squares calculations. To get these calculations, the sum of squares option needs to be added (`/ ss1 ss2 ss3 ss4`

) to the model statement.

```
proc glm;
class drug disease;=drug disease drug*disease / ss1 ss2 ss3 ss4;
model y run;
```