In the MBC Manual i read:

MBC also reports two-way choice likelihoods of items (how often each combination of two levels was chosen).

If my questionnaire contains 5 menu choices

A

B

C

D

E

and i'm interested in the two-way choice likelihoods of A and B, are the reported two-way probabilities:

a) The combination of only A x B

OR

b) The combination of all possible ways of A x B occur together?

(A x B) + (A x B x C) + (A x B x D) ... (A x B x C x D x E)

I assume actual and expected likelihoods (for calculating synergy effects) are based on the same calculation?

Thanks