Dear all

I did not find the coding rules to express quadratic formula in Anova. The SO() & PQ() command allow to build such a model, but unfortunately, the resulting info is not separated along terms of the model but grouped instead. This command

Quad_SO <- aov(Data ~ SO(H1,H2,H3))

followed by : anova(Quad_SO)" gives :

```
Df Sum Sq Mean F value Pr(>F)
```

**SO(H1, H2, H3, H4, H5)** 20 9.7 0.48 125.33 2.2e-16

Even worst,

rsm_SO <- rsm(Data~ SO(H1,H2,H3))

gives an horrible terms naming which makes sensitivity bargraph unreadable...

..... **TWI(H1, H2, H3)H1:H3...... PQ(H1, H2, H3)H3^2

I have not found any relevant example on how generate quadratic model using symbolic notation or a way to expand terms from SO or PQ commands

Thanks a lot for you help...