# Comparison between contrasts in emmeans

Let's say I have these estimated marginal means:

> emm <- emmeans(Model5, ~ Measurement * Condition)
> emm
Measurement Condition emmean     SE   df lower.CL upper.CL
B           L           7.98 0.0474 1788     7.89     8.07
1           L           7.97 0.0474 1788     7.88     8.06
2           L           8.04 0.0474 1788     7.95     8.14
B           N           7.96 0.0474 1788     7.87     8.05
1           N           8.00 0.0474 1788     7.91     8.10
2           N           7.93 0.0474 1788     7.84     8.03


I want to check for significance, insider condition N: B vs 1 compared to B vs 2.

How can I do that?

I only found a way to do straightforward contrasts:

contrast(emm, list(
"N_B vs N_1 " = c(0, 0, 0, -1, 1, 0, 0, 0, 0, 0, 0, 0)
))


but not to do a comparison between two contrasts.

## 1 Answer

And in general, there is an index to all the vignettes in the emmeans package, and you can often find answers to questions like this.

But a quick answer to thgis question is

contrast(emm, interaction = "consec")


which constructs all interaction contrasts involving consecutive levels of each factor.