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I've got back reviews for a paper I've submitted, with the following problem.

I have two logistic regression models, say y ~ A, and y ~ A + B, where B is a factor with several levels. I have performed a likelihood ratio test between them, and it is highly significant. My goal is to show that B has some independent information about the response and thus improves model fit "signficantly" (loaded term) above and beyond A, and I think the LRT shows this very strongly.

The reviewer is not happy with this, they suggest using a different approach of comparing the "change of significance of B between two models": y ~ B vs y ~ A + B, which to me sounds like the Wald test for B in the A + B model, even though the reviewer doesn't realise it.

Given that B has multiple levels and thus multiple Wald tests, it seems to me the LRT is more useful and more powerful (also no multiple testing issue).

Am I right? Are there any nice (not too abstract) references I can use to back these claims?

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Wald vs likelihood ratio is secondary to the fact that comparing $y\sim B$ to $y\sim A+B$ is a test of $A$, not a test of $B$. I hope this is a typo in the referee report.

Agresti’s Foundations of Linear and Generalized Linear Models gives some reasons to prefer likelihood ratio testing to Wald testing in logistic regression, though the difference usually is not considerable. However, the reviewer is all kinds of wrong to have you testing $A$ to say how good of a predictor $B$ is. That is roughly equivalent to running ANCOVA by testing the slope instead of the factor—complete nonsense.

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  • $\begingroup$ I somehow overlooked that issue while focusing on the title. Even if it were a typo, the phrase "change of significance of B between two models" wouldn't make sense as $B$ would only be present in one of the two models. $\endgroup$
    – statmerkur
    Commented Jan 4, 2023 at 14:09
  • $\begingroup$ @statmerkur Yikes, then it seems the reviewer really wants you to test $A$. Consider pushing back on this and requesting an explanation for why the reviewer wants you to test the wrong variable. We have Academia Stack Exchange as a resource to ask how to phrase this in your response. $\endgroup$
    – Dave
    Commented Jan 4, 2023 at 14:11
  • $\begingroup$ I'm not the OP! As you are the one that noticed that issue first, I would encourage you to ask the OP for clarification first, if you like. I've deleted my answer for now. $\endgroup$
    – statmerkur
    Commented Jan 4, 2023 at 15:58

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