margins.multinom - Error in jacobian %*% vcov : non-conformable arguments

[gerjonhannink]

Hi Thomas,

I get an error message (Error in jacobian %*% vcov : non-conformable arguments) when running margins on a multinom-object. This issue has also been mentioned by someone else here.

Can you help me out? Many thanks!

Kind regards, Gerjon

## load package
library(nnet)
library(margins)

## code goes here
data(mtcars)
mtcars$am <- factor(mtcars$am)

fit_multinom <- multinom(cyl ~ am, mtcars)

summary(margins(fit_multinom, variables = "am"))
# Error in jacobian %*% vcov : non-conformable arguments

## session info
R version 4.0.5 (2021-03-31)
Platform: x86_64-apple-darwin17.0 (64-bit)
Running under: macOS Big Sur 10.16

Matrix products: default
LAPACK: /Library/Frameworks/R.framework/Versions/4.0/Resources/lib/libRlapack.dylib

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] margins_0.3.26 descr_1.1.5    nnet_7.3-15    rio_0.5.26    

loaded via a namespace (and not attached):
 [1] Rcpp_1.0.6        knitr_1.31        magrittr_2.0.1    MASS_7.3-53.1     hms_1.0.0        
 [6] xtable_1.8-4      rlang_0.4.10      fansi_0.4.2       tools_4.0.5       data.table_1.14.0
[11] xfun_0.22         tinytex_0.29      utf8_1.2.1        htmltools_0.5.1.1 ellipsis_0.3.1   
[16] readxl_1.3.1      yaml_2.2.1        digest_0.6.27     tibble_3.1.0      lifecycle_1.0.0  
[21] prediction_0.3.14 crayon_1.4.1      zip_2.1.1         vctrs_0.3.7       curl_4.3         
[26] evaluate_0.14     haven_2.3.1       rmarkdown_2.6     openxlsx_4.2.3    stringi_1.5.3    
[31] cellranger_1.1.0  compiler_4.0.5    pillar_1.5.1      forcats_0.5.1     foreign_0.8-81   
[36] pkgconfig_2.0.3  

[gbufton]

I am also impacted by this issue!

[jkhanson1970]

I am seeing it too. Notably, I'm using code and data that I am sure worked fine in Sept 2020, when I used it for my econometrics class.

[IdaHjermitslev]

me too

[Keniajin]

Experiencing the same error, but when I changed the vce ="bootstrap" it worked. However, the estimates of the p-values are very different from Stata margins