Choosing choices: Agenda selection with uncertain issues

This paper studies selection rules i.e. the procedures committees use to choose whether to place an issue on their agenda. The main ingredient of the model is that committee members are uncertain about their final preferences at the selection stage: they only know the probability that they will eventually prefer the proposal to the status quo at the decision stage. This probability is private information. We find that a more stringent selection rule makes the voters more conservative. Hence individual behavior reinforces the effect of the rule instead of balancing it. For a voter, conditional on being pivotal, the probability that the proposal is adopted depends on which option she eventually favors. The probability that the proposal is adopted if she eventually prefers the proposal increases at a higher rate with the selection rule than if she eventually prefers the status quo. In order to compensate for that, the voters become more selective. The decision rule has the opposite effect. We describe optimal rules when there is a fixed cost of organizing the final election.selection rules ; strategic voting ; asymmetric information ; agenda setting ; large deviations ; petitions ; citizens' initiative

Complicating to Persuade?

This paper addresses a common criticism of certification processes: that they simultaneously generate excessive complexity, insuficient scrutiny and high rates of undue validation. We build a model of persuasion in which low and high types pool on their choice of complexity. A natural criterion based on forward induction selects the high-type optimal pooling equilibrium.When the receiver prefers rejection ex ante, the sender simplifies her report. When the receiver prefers validation ex ante, however, more complexity makes the receiver less selective, and we provide sufficient conditions that lead to complexity inflation in equilibrium

Test Design Under Falsification

We study the optimal design of tests with manipulable inputs. Tests take a unidimensional state of the world as input and output, an informative signal to guide a receiver's approve or reject decision. The receiver wishes to only approve states that comply with her baseline standard. An agent with a preference for approval can covertly falsify the state of the world at a cost. We characterize receiver-optimal tests and show they rely on productive falsification by compliant states. They work by setting a more stringent operational standard, and granting noncompliant states a positive approval probability to deter them from falsifying to the standard. We also study how falsification-detection technologies improve optimal tests. They allow the designer to build an implicit cost of falsification into the test, in the form of signal devaluations. Exploiting this channel requires enriching the signal space

Score-based mechanisms

We propose a mechanism design framework that incorporates both soft information, which can be freely manipulated, and semi-hard information, which entails a cost for falsification. The framework captures various contexts such as school choice, public housing, organ transplant and manipulations of classification algorithms. We first provide a canonical class of mechanisms for these settings. The key idea is to treat the submission of hard information as an observable and payoff-relevant action and the contractible part of the mechanism as a mapping from submitted scores to a distribution over decisions (a score-based decision rule). Each type report triggers a distribution over score submission requests and a distribution over decision rules. We provide conditions under which score-based mechanisms are without loss of generality. In other words, situations under which the agent does not make any type reports and decides without a mediator what score to submit in a score-based decision rule. We proceed to characterize optimal approval mechanisms in the presence of manipulable hard information. In several leading settings optimal mechanisms are score-based (and thus do not rely on soft information) and involve costly screening. The solution methodology we employ is suitable both for concave cost functions and quadratic costs and is applicable to a wide range of contexts in economics and in computer science

Synthetic studies of heparan derivatives: Glycosyl couplings and post-glycosylative modifications

Heparan sulfate (HS) and closely related heparin are comprised of alternating units of D-glucosamine and either D-glucuronic acid (D-GluA) or L-iduronic acid (L-IdoA), and support variable degrees of sulfation which can interact with a large number of proteins with diverse biological functions. HS oligosaccharides can be constructed from readily accessible D-GlcN and D-GlcA derivatives, but the inclusion of L-IdoA is less straightforward. To address this, our laboratory has developed alternative synthetic strategies for HS-like oligosaccharides to incorporate either D-GlcA or L-IdoA in a synthetically efficient manner by nucleophilic ring opening of 4-epoxypyranosides, which can be made from readily available D-hexoses in few steps. These are derived from 4-deoxypentenosides (4-DPs), unsaturated pyranosides that can be linked with other sugars, enabling us to investigate synthetic strategies involving post-glycosylative modifications. Terminal 4-DPs have been generated at a late stage from β-1,4-linked disaccharides, and also by stereoselective coupling of 4-DP thioglycoside donors with various acceptors. The 4’-enol ether can be modified by stereoselective epoxidation and ring opening by a dithiocarbamate auxiliary, which can be activated by copper(I) salts for carbon nucleophile addition with terminal L-ido configuration. We also explored stereoselective glycosylation of a novel glucosamine donor with a N-diphenylphosphinamido group

Competing with Equivocal Information

This paper studies strategic disclosure by multiple senders competing for prizes awarded by a single receiver. They decide whether to disclose a piece of information that is both verifiable and equivocal (it can influence the receiver both ways). The standard unraveling argument breaks down: if the commonly known probability that her information is favorable is high, a single sender never discloses. Competition restores full disclosure only if some of the senders are sufficiently unlikely to have favorable information. When the senders are uncertain about each other’s strength, however, all symmetric equilibria approach full disclosure as competition increases