rPackages.mlogit: missing `effects()` function

Nixpkgs version

• Unstable (26.05)

Describe the bug

I am using the mlogit library in R. Everything seems fine, except the effects() function described in the documentation simply doesn't exist?! If I type mlogit:: and tab, all other functions appear, but not the effects function. (mlogit.effects doesn't appear either.) Invoking the effects function after loading the library fails, as it uses the one from stats. It is missing in both the stable and unstable versions.

Steps to reproduce

Using this flake:

{
  description = "A basic flake with a shell";
  inputs.nixpkgs.url = "github:NixOS/nixpkgs/25.11";
  inputs.systems.url = "github:nix-systems/default";
  inputs.flake-utils = {
    url = "github:numtide/flake-utils";
    inputs.systems.follows = "systems";
  };

  outputs =
    { nixpkgs, flake-utils, ... }:
    flake-utils.lib.eachDefaultSystem (
      system:
      let
        pkgs = nixpkgs.legacyPackages.${system};
      in
      {
        devShells.default = pkgs.mkShell {
          nativeBuildInputs = [ pkgs.bashInteractive ];
          buildInputs = with pkgs; [
            R
            (with rPackages; [
              mlogit
            ])
          ];
        };
      }
    );
}

Enter an R session, type mlogit:: and tab twice to see the list of available functions with the effects function missing.

Expected behaviour

The function exists.

Screenshots

No response

Relevant log output

Additional context

No response

System metadata

❯ nix-shell -p nix-info --run "nix-info -m"

• system: "x86_64-linux"
• host os: Linux 6.18.21, NixOS, 26.05 (Yarara), 26.05.20260409.4c1018d
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.31.4
• channels(root): "nixos-23.11"
• nixpkgs: /nix/store/anvdcc2arw7kqrvwnidvhw6ypkkvws68-source

Notify maintainers

---

Note for maintainers: Please tag this issue in your pull request description. (i.e. Resolves #ISSUE.)

I assert that this issue is relevant for Nixpkgs

• I assert that this is a bug and not a support request.
• I assert that this is not a duplicate of an existing issue.
• I assert that I have read the NixOS Code of Conduct and agree to abide by it.

Is this issue important to you?

Add a 👍 reaction to issues you find important.

Start by locating the nixpkgs package expression for rPackages.mlogit and compare the installed package version and exported namespace with the CRAN documentation. Reproduce the flake, then verify that mlogit::effects is available and that the package checks pass.