- Queen Mary University of London
Wednesday, February 3, 2021
Zoom webinar: https://univr.zoom.us/j/81832336065
We consider a model of “approval behaviour” (like Favouriting, Sharing or Wish-listing) for items presented as a list. The approver proceeds to each successive item with a continuation probability that depends on the history of predecessors,approving along the way any item that is considered “acceptable” (e.g., possess-ing a set of key properties). The procedure is the only one that satisfies Predecessor Monotonicity (the approval probability of an item is non-increasing when the sublist of predecessors lengthens) and Approval Luce Independence (the approval odds for two items when they have the same sublist of predecessors are invariant to the exact identity and listing of the predecessors). The primitives of the model are substantially identified from behaviour. If there are correlations between continuation and acceptability, then Luce Approval Independence is replaced in the characterisation by Monotone Differences (an item’s revealed quality and its position in the list are complementary in the production of approval). Finally, we explore the notion of “list design”.