Hi, thanks for the reply!

1) The issue with the z-tests is not related to the new version. It's due to the data length. GAMLj uses R package `emmeans` to estimate both simple effects and posthoc tests. With the mixed model, we set the degrees of freedom options to `satterhwaite` to obtain the t-test. However, when the data are very long, emmeans switches to the 'asymptotic` method, so it yields a z-test. This is wise because with a large dataset the computation of the t-test may become very slow and resources consuming. If you had run it in R with `emmeans()`, you'd get:

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`Note: D.f. calculations have been disabled because the number of observations exceeds 25000.`

To enable adjustments, add the argument 'lmerTest.limit = 37248' (or larger)

[or, globally, 'set emm_options(lmerTest.limit = 37248)' or larger];

but be warned that this may result in large computation time and memory use.

This is wise also because when you have so many df (in your case 370001), the z-test and the t-tests are perfectly the same, so there's no need to wait for a half-hour for a result that is known to be equivalent. Indeed, I forced the calculation of the t-test in your dataset and I got the t-tests exactly equals to the z-tests, with 370001 df. So, if you want to report the results in terms of t-tests, just report the z-test values, with 370001 df. If you want to see that that is correct, do the following:

Go to option panel `Factor coding` and set Valence to `dummy`. Look at the `Fixed Effects Parameter Estimates` table, the row corresponding to `Warmth1 warm-cold`. That is now the simple effect of Warmth computed for Valence=NEGATIVE, because with `dummy` scoring we score valence as 0 and 1, so the other effects are computed for valence=0.

You can see that the coefficient, the CI, and the rest are all identical to the `Simple effects` table, row Negative. You can also see that the t-test in `Parameter Estimates` is -13.3 (rounded) as it is the z-test in Simple Effects. The df are 370001, as expected.

The same goes for the post-hoc tests.

2) As regards the fact that you do not see the labels of the second column of the posthoc table, I cannot reproduce it, so it may have to do with the locale (different computer setups, fonts, and the like). I'll investigate this and fix it, thanks for mentioning it.

It should be like this

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`Post Hoc Comparisons - Valence ✻ Warmth`

Comparison

Valence Warmth Valence Warmth

Negative Cold - Negative Warm

Negative Cold - Positive Cold

Negative Cold - Positive Warm

Negative Warm - Positive Warm

Positive Cold - Negative Warm

Positive Cold - Positive Warm