  Motivated by applications in retail, online advertising, and cultural
markets, this paper studies how to find the optimal assortment and positioning
of products subject to a capacity constraint. We prove that the optimal
assortment and positioning can be found in polynomial time for a multinomial
logit model capturing utilities, position bias, and social influence. Moreover,
in a dynamic market, we show that the policy that applies the optimal
assortment and positioning and leverages social influence outperforms in
expectation any policy not using social influence.
