  This paper formulates the protocol for prediction of packs, which a special
case of prediction under delayed feedback. Under this protocol, the learner
must make a few predictions without seeing the outcomes and then the outcomes
are revealed. We develop the theory of prediction with expert advice for packs.
By applying Vovk's Aggregating Algorithm to this problem we obtain a number of
algorithms with tight upper bounds. We carry out empirical experiments on
housing data.
