  In this paper we consider a multiple access channel (MAC) with partial
cribbing encoders. This means that each of two encoders obtains a deterministic
function of the other encoder output with or without delay. The partial
cribbing scheme is especially motivated by the additive noise Gaussian MAC
since perfect cribbing results in the degenerated case of full cooperation
between the encoders and requires an infinite entropy link. We derive a single
letter characterization of the capacity of the MAC with partial cribbing for
the cases of causal and strictly causal partial cribbing. Several numerical
examples, such as quantized cribbing, are presented. We further consider and
derive the capacity region where the cribbing depends on actions that are
functions of the previous cribbed observations. In particular, we consider a
scenario where the action is "to crib or not to crib" and show that a naive
time-sharing strategy is not optimal.
