Is there a way to extract column names of an object created from ModelMatrix() so that I can use those columns as row names for coefficients? Thanks.

[image] sbohor3: object created from ModelMatrix() This isn’t standard Julia. Is this part of some package?

Actually, I am writing a Julia function for a stat method in which I need to use ModelMatrix and would like to obtain the levels of the covariates from the ModelMatrix so I can use them to name the coefficients in the output. Thanks.

Oh, you should’ve mentioned that this is a DataFrames.jl thing. http://juliastats.github.io/DataFrames.jl/latest/man/formulas/#The-Formula,-ModelFrame-and-ModelMatrix-Types-1 Edited for clarity.

Oh sorry, yes I was referring to ModelMatrix in DataFrame.jl. I cannot obtain the column names from an object created from ModelMatrix(). Any idea? Thanks. So

You don’t have access to the names at the ModelMatrix stage. You’d need the ModelFrame for that.

Thanks. Would ModelFrame give me columns by creating dummy indicators of levels of factor variables? Thanks,

No that is what ModelMatrix does but from a mf::ModelFrame you can get the ModelMatrix with ModelMatrix(mf) and the column names with coefnames(mf).

@andreasnoack @ChrisRackauckas : Below is an example of the same problem addressed in R language. Notice how levels (1s) of factor variables are attached to the column variables am and vs. I would like to do the same in Julia so that I can access the names (columns) from design matrix. Thanks. > ta…

@andreasnoack : Thanks a lot. That’s what I wanted.

@andreasnoack : Is there any way to boost the speed of Pkg.add() or using packages? These are too slow. Thanks.

Get columns of DataFrames.jl ModelMatrix object

Specific Domains Statistics

Topic		Replies	Views
StatsModels: get levels and model matrix for each level of categorical term New to Julia question	2	414	March 15, 2021
How to remove specific collumn from ModelFrame (StatsModels.jl)? Statistics	11	494	December 24, 2023
Getting model parameter names from DataFrame General Usage turing	5	612	November 19, 2020
Julia equivalent of the R function `model.matrix` General Usage statistics	2	1061	October 31, 2020
Having trouble with StatsModels.jl `modelmatrix` to replicate R results Statistics	1	95	April 11, 2025

Get columns of DataFrames.jl ModelMatrix object

Related topics