Change dummy/effects coded omitted parameter value

[JK2020]

Hi there,

On page 112 of the Ngene Manual (version 1.2.0), there is a quote "Example syntax is presented below for the color example, where the first color level has been assigned a prior parameter value of -0.15, the second 0.45 and the final omitted level, a value of zero."

The syntax described is:

U(alt1) = color.dummy[-0.15|0.45] * color

Is it possible to recode the 'final omitted level' to be 1 instead of 0?


The reason I want to do this is that I am using priors from health economics DCEs that are scaled from 0 (worst possible state) to 1 (best possible state).

This is a made up example but let's say I have a pain attribute with 3 levels that represent severe pain, moderate pain, no pain:

Pain.d[0.76 | 0.87]*Pain[0,1,2]

It then assumes that my level 2 (no pain) is 0, which is quite far from the truth (it's probably close to 1).

[Michiel Bliemer]

You cannot change dummy coding, which always has a reference level with zero utility, but you can change the attribute level that is the reference and you can change the order of the levels.

So instead of Pain[0,1,2] you could write Pain[2,1,0], where 0 is now the reference level with zero utility. The last level is always the reference level in Ngene, but you change choose the order of 0, 1, and 2.

Michiel

[JK2020]

Thank you! I think that should work