No Trade, Informed Trading, and Accuracy of Information.

We present a model in which there is uncertainty about realization of a risky asset value for an informed trader. Then, we show that the informed trader does not trade in equi- librium if the inside information the informed trader has is not sufficiently accurate. We use the framework presented by Glosten and Milgrom (1985) and extend the assumption that the informed trader knows the terminal value of the risky asset. Finally, we obtain the conditions under which the informed trader would not trade in equilibrium.

Price, Trade Size, and Information Revelation in Multi-Period Securities Markets

We study price formation in securities markets, using the sequential trade framework of Glosten and Milgrom. This paper makes one basic methodological advance over previous research on sequential securities trading: we allow for multiple trade sizes for traders to choose from in a multi-period market. We examine how trade size multiplicity affects the intertemporal dynamics of trading strategies, bid-ask spreads, and information revelation. We also show that price impact, as a function of trade size, is increasing and exhibits (discrete) concavity.

A Unifying Impossibility Theorem

This paper considers social choice correspondences assigning a choice set to each non-empty subset of social alternatives. We impose three requirements on these correspondences: unanimity, independence of preferences over infeasible alternatives and choice consistency with respect to choices out of all possible alternatives. With more than three social alternatives and the universal preference domain, any social choice correspondence that satisfies our requirements is serially dictatorial. A number of known impossibility theorems — including Arrow’s Impossibility Theorem, the Muller-Satterthwaite Theorem and the impossibility theorem under strategic candidacy — follow as corollaries. Our new proof highlights the common logical underpinnings behind these theorems.

A Hierarchical Agency Model of Deposit Insurance

This paper develops a hierarchical agency model of deposit insurance. The main purpose is to undertake a game theoretic analysis of the consequences of deposit insurance schemes and their effects on monitoring incentives for banks. Using this simple framework, we analyze both risk- independent and risk-dependent premium schemes along with reserve requirement constraints. The results provide policymakers with not only a better understanding of the effects of deposit insurance on welfare and the problem of moral hazard, but also the policy implications implied in the design of de- posit insurance schemes. Our finding is consistent with the empirical research on depositor discipline.

No Trade, Informed Trading, and Accuracy of Information

We present a model in which there is uncertainty about realization of a risky asset value for an informed trader. We introduce two states such that in the "narrow" state the informed trader has better information than in the "wide" state. Then, we show that the informed trader in the wide state does not trade in equilibrium if the information that the informed trader with better information has is sufficiently accurate and the probability of the narrow state is sufficiently high. We use the framework presented by Glosten and Milgrom (1985) and extend the assumption that the informed trader knows the terminal value of the risky asset. Finally, we obtain the conditions under which the informed trader would not trade in equilibrium.Market microstructure; Glosten-Milgrom; Price formation; Asymmetric information; Bid-ask spreads.

Temperature dependence of inter-dot electron-spin transfer among laterally coupled excited states in high-density InGaAs quantum dots

The temperature dependence of interdot spin-transfer dynamics at laterally coupled excited states (ESs) in high-density InGaAs quantum dots (QDs) was studied using spin- and time-resolved photoluminescence spectroscopy. At low temperatures below 100 K, temporary suppression of electron-spin polarization decay due to selective relaxation of minority spins from emissive ESs to lower-energy states in neighboring QDs was observed. In the temperature range from 20 K to 140 K, thermal activation of electron spins from lower-energy QD states to higher-energy states via interdot transfer prevents the aforementioned selective relaxation of minority spins, leading to a faster decay of electron-spin polarization during light emission. At high temperatures above 140 K, reinjection of depolarized electron spins from barriers after thermal escape from QD ESs accelerates the further decay of the electron-spin polarization, wherein the electron spins can be activated via ladderlike interdot transfer. These findings indicate that the suppression of reinjection of electron spins from barriers in a high-density QD system is crucial for maintaining high electron-spin polarization during light emission at high temperatures. Published under license by AIP Publishing