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arXiv · 2406.19063

Convex Choice

Navin Kartik·Andreas Kleiner
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Abstract

For multidimensional Euclidean type spaces, we study convex choice: from any choice set, the set of types that make the same choice is convex. We establish that, in a suitable sense, this property characterizes the sufficiency of local incentive constraints. Convex choice is also of interest more broadly. We tie convex choice to a notion of directional single-crossing differences (DSCD). For an expected-utility agent choosing among lotteries, DSCD implies that preferences are either one-dimensional or must take the affine form that has been tractable in multidimensional mechanism design.

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Navin Kartik, Andreas Kleiner. 2024-06-27. Convex Choice. https://arxiv.org/abs/2406.19063

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