Alex Frankel Publications

Signaling is wasteful. But how wasteful? We study the fraction of surplus dissipated in a separating equilibrium. For isoelastic environments, this waste ratio has a simple formula: β/(β + σ), where β is the benefit elasticity (reward to higher perception) and σ is the elasticity of higher types’ relative cost advantage. The ratio is constant across types and is independent of other parameters, including convexity of cost in the signal. We show that the directional effects of β and σ on waste extend to non-isoelastic environments.

Signaling is wasteful. But how wasteful? We study the fraction of surplus dissipated in a separating equilibrium. For isoelastic environments, this waste ratio has a simple formula: β/(β + σ), where β is the benefit elasticity (reward to higher perception) and σ is the elasticity of higher types’ relative cost advantage. The ratio is constant across types and independent of other parameters, including convexity of cost in the signal. A constant waste ratio characterizes the isoelastic class. In winner-take-all signaling tournaments with N candidates, exactly (N − 1)/N of the surplus dissipates—the same as in Tullock contests.

Many US colleges now use test-optional admissions. A frequent claim is that by not seeing standardized test scores, a college can admit a student body it prefers, say, with more diversity. But how can observing less information improve decisions? This paper proposes that test-optional policies are a response to social pressure on admission decisions. We model a college that bears disutility when it makes admission decisions that "society" dislikes. Going test optional allows the college to reduce its "disagreement cost." We analyze how missing scores are imputed and the consequences for the college, students, and society.

US colleges often justify test-optional admissions policies as promoting diversity by reducing their reliance on standardized test scores. But a college that mandates test scores can decide how to use those scores. Wouldn't more information allow a college to make decisions it prefers? Indeed, this paper identifies a broad set of assumptions under which test-mandatory policies are always weakly better for colleges. We then discuss how alternative assumptions might rationalize test-optional policies.

We study a model of signaling in which agents are heterogeneous on two dimensions. An agent’s natural action is the action taken in the absence of signaling concerns. Her gaming ability parameterizes the cost of increasing the action. Equilibrium behavior muddles information across dimensions. As incentives to take higher actions increase—due to higher stakes or more manipulable signaling technology—more information is revealed about gaming ability, and less about natural actions. We explore a new externality: showing agents’ actions to additional observers can worsen information for existing observers. Applications to credit scoring, school testing, and web searching are discussed.