what does "Lowest coded group" mean in reference to categorical variables in multiple logistic regression

Hi everyone,

I have been reading up on the use of categorical variables in multiple logistic regression and have come across phrases like this one a couple of times stating that for categorical variables the coefficients give log odds for each categories effect on the variable of interest relative to the reference category and that in r the default is that the "reference group is the lowest coded group" , but I am having a hard time figuring out what is meant by the lowest coded group? Thanks so much for any insight.

Is it just as simple as that each level in the factor data is assigned a number and that reference number is the code that is being referred to? Thanks

The lowest coded group is the first one in the list of levels in the factor. It is stored with the value 1. The default ordering is alphabetical.

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