Multiple imputation example not working

[mhoenicka]

Hi,
I've been trying to adapt the Amelia sample code on the multiple imputations vignette (https://marginaleffects.com/vignettes/multiple_imputation.html) to my own project. As this resulted in an error message, I copypasted the provided example in the Amelia section and ran that one. Same error message:

mod_amelia <- with(dat_amelia, lm(Petal.Width ~ Sepal.Length * Sepal.Width + Species))
Error in eval(predvars, data, env) : object 'Petal.Width' not found

My environment at work is provided below. The same error occurs on an up-to-date FreeBSD system at home, I can supply the sessionInfo() output of my homebox too if needed.
Any idea how to fix this?
Markus

sessionInfo()
R version 3.6.3 (2020-02-29)
Platform: x86_64-pc-cygwin (64-bit)
Running under: CYGWIN_NT-10.0 PC6187 3.1.6(0.340/5/3) 2020-07-09 08:20 x86_64 Cygwin

Matrix products: default
LAPACK: /usr/lib/R/modules/lapack.dll

locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8

attached base packages:
[1] stats graphics grDevices utils datasets methods base

other attached packages:
[1] Amelia_1.7.6 Rcpp_1.0.4.6 marginaleffects_0.19.0

loaded via a namespace (and not attached):
[1] compiler_3.6.3 cli_3.6.1 generics_0.1.3 foreign_0.8-75
[5] data.table_1.12.8 rlang_1.1.0

[vincentarelbundock]

There is no marginaleffects code at all in the example you give. This appears to be unrelated to marginaleffects, so I'm not sure what can be discussed here, exactly. Maybe this question should be targeted to an Amelia forum?

FWIW, I copied the code from the vignette in a fresh R session and everything works as intended.

[mhoenicka]

Well, the next line would have been a call to avg_slopes() if the Amelia code hadn't failed on me - I failed to mention that I want to use avg_slopes() on imputed datasets. But you are right, of course. I tried the sample code in a fresh environment on my FreeBSD box, and sure enough it worked like a charm. I'll trace back my steps and see why it failed in my work environment.
Thx, Markus

[vincentarelbundock]

Yep yep, makes sense. Glad it now seems to be working on at least one machine!