Short-term equity dynamics and endogenous market fluctuations

Capital growth and survival strategies in a market with endogenous prices

We call an investment strategy survival, if an agent who uses it maintains a non-vanishing share of market wealth over the infinite time horizon. In a discrete-time multi-agent model with endogenous asset prices determined through a short-run equilibrium of supply and demand, we show that a survival strategy can be constructed as follows: an agent should assume that only their actions determine the prices and use a growth optimal (log-optimal) strategy with respect to these prices, disregarding the actual prices. Then any survival strategy turns out to be close to this strategy asymptotically.…

基于排名依赖的进出机制的股票市场中的行波

Traveling Waves in Equity Markets with Rank-Based Entry and Exit

该研究通过带排名依赖进出机制的几何布朗运动粒子模型，结合CRSP数据校准，证明股票市场长期资本分布为行波，且换手率稳定市场，该行波可拟合经验分布并确定多元化投资组合的资本增长。

Perfect hedging under endogenous permanent market impacts

We model a nonlinear price curve quoted in a market as the utility indifference curve of a representative liquidity supplier. As the utility function we adopt a g-expectation. In contrast to the standard framework of financial engineering, a trader is no more price taker as any trade has a permanent market impact via an effect to the supplier's inventory. The P&L of a trading strategy is written as a nonlinear stochastic integral. Under this market impact model, we introduce a completeness condition under which any derivative can be perfectly replicated by a dynamic trading strategy. In the sp…

Atlas models of equity markets

Atlas-type models are constant-parameter models of uncorrelated stocks for equity markets with a stable capital distribution, in which the growth rates and variances depend on rank. The simplest such model assigns the same, constant variance to all stocks; zero rate of growth to all stocks but the smallest; and positive growth rate to the smallest, the Atlas stock. In this paper we study the basic properties of this class of models, as well as the behavior of various portfolios in their midst. Of particular interest are portfolios that do not contain the Atlas stock.

Diversity and relative arbitrage in equity markets

A financial market is called "diverse" if no single stock is ever allowed to dominate the entire market in terms of relative capitalization. In the context of the standard Ito-process model initiated by Samuelson (1965) we formulate this property (and the allied, successively weaker notions of "weak diversity" and "asymptotic weak diversity") in precise terms. We show that diversity is possible to achieve, but delicate. Several illustrative examples are provided, which demonstrate that weakly-diverse financial markets contain relative arbitrage opportunities: it is possible to outperform (or u…

在内生定价下的效用最大化

Utility maximization under endogenous pricing

本文研究了在内生定价机制下，大型投资者如何通过解决非线性后向随机偏微分方程来实现预期效用最大化，并探讨了不同条件下的解存在性和光滑性。