emmeans - joint effects of interaction terms

I would like to see the joint effects of an interaction term. I tried joint_tests() but it gives f ratios. However, I would prefer Incidence Rate Ratios (IRR) because the rest of my results section uses those. My model is a GLMM with Poisson distribution. Any ideas?

I also tried the following but the outcome remains the same:

EMM <- emmeans(model1, ~ A | B)
PRS <- contrast(EMM, "revpairwise", interaction = "consec")
summary(PRS)
summary(PRS, type = "response", infer = c(TRUE, TRUE))


Thank you in advance!

• Is IRR really interval rate ratios, or do you mean incidence rate ratios? I'm well familiar with Poisson models for estimating the latter, but have never heard of the former Oct 13 at 21:48
• You can use, say, contrast(emm, interaction = "consec") to obtain comparisons of comparisons at consecutive levels. See the vignette on interactions. Oct 13 at 23:58
• @RussLenth Hi, I've tried that but my outcome is the same, any advice? I quickly added your suggestion in the question to show what I did. Oct 14 at 6:06
• @AdamO Yes, you are right. Oct 14 at 6:11
• Thee are two things wrong. One, you asked for both regular contrasts and interaction contrasts. So decide which (interaction I think, but I'm never sure I understand what you want). Second, if you do want interaction contrasts, your EMM has B as a by variable, so A is out there by itself with nothing to interact with. Try contrast(EMM, interaction = "consec", by = NULL). And also think about this and do your best to understand why. Oct 14 at 20:04