# Creating multiline labels in xy-pics, xy-matrix or similar

I would like to make a diagram that shows the order in which i used some models. I normally make diagrams with xy-matrix, but some of the model names would look clumsy if kept on a single line, so I'd like to be able to make them run over separate lines and look something like:

model 1

Model 2

Model 2

simplified

Model 3

I realise that this may be beyond the bounds of what xy-matrix can do, in which case could anyone advise me a quick way of making this kind of diagram with another package?

\documentclass{article}
$\xymatrix@R-2ex{ \txt{Model 1} \ar[d] \\ \txt{Model 2} \ar[d] \\ \txt{Model 2\\simplified} \ar[d] \\ \txt{Model 3} }$