[Gretl-users] questions about nonlinearity tests

Hi, I was checking the status quo of specification tests for (or against...) nonlinearity in gretl. In the guide a quick search didn't reveal anything. In the command reference for "modtest" I see two options labeled "--logs (nonlinearity, logs)" and "--squares (nonlinearity, squares)". But the description doesn't provide more information apart from being a LM-type test. Is there more information somewhere? Furthermore, it suggests that those tests only apply to ols estimation, but my idea was to run a check after an ARMA model. Perhaps we could try to implement something that works there? thanks sven