A model of optimal portfolio selection under liquidity risk and price impact

We study a financial model with one risk-free and one risky asset subject to liquidity risk and price impact. In this market, an investor may transfer funds between the two assets at any discrete time. Each purchase or sale policy decision affects the rice of the risky asset and incurs some fixed transaction cost. The objective is to maximize the expected utility from terminal liquidation value over a finite horizon and subject to a solvency constraint. This is formulated as an impulse control problem under state constraints and we characterize the value function as the unique constrained viscosity solution to the associated quasi-variational Hamilton–Jacobi–Bellman inequality. We would like to thank Mihail Zervos for useful discussions.     

Optimal liquidation under stochastic liquidity

We solve explicitly a two-dimensional singular control problem of finite fuel type for an infinite time horizon. The problem stems from the optimal liquidation of an asset position in a financial market with multiplicative and transient price impact. Liquidity is stochastic in that the volume effect process, which determines the intertemporal resilience of the market in the spirit of Predoiu et al. (SIAM J. Financ. Math. 2:183–212, 2011), is taken to be stochastic, being driven by its own random noise. The optimal control is obtained as the local time of a diffusion process reflected at a non-constant free boundary. To solve the HJB variational inequality and prove optimality, we need a combination of probabilistic arguments and calculus of variations methods, involving Laplace transforms of inverse local times for diffusions reflected at elastic boundaries.     

Redistributive taxation and social insurance under adverse selection in the insurance market

This paper extends the analysis of optimal income taxation under uncertainty studied by Cremer and Pestieau (International Tax and Public Finance, 3, 281–295, 1996). We introduce asymmetric information in the insurance market whereby private insurance companies cannot identify the risk probability of the agents, and we examine its effect on public policy. We consider the separating equilibrium of Rothschild and Stiglitz (Quarterly Journal of Economics, 90, 629–649, 1976) and Riley (Econometrica, 47, 331–359, 1979) where the low risk agent is only partially insured. The presence of the distortion in the insurance market changes the affinity of labor, and in some cases, we show that the scope of redistribution and the resulting social welfare are higher under asymmetric information than under full information. We also show that the increase in social insurance affects the utility and labor incentive of the low risk type by relaxing the self-selection constraint in the insurance market. The policy implications of the redistributive taxation and social insurance are analytically and numerically examined.      

Corporate liquidity and dividend policy under uncertainty

We examine optimal liquidity (retained earnings) and dividend choice incorporating debt financing with risk of default and bankruptcy costs as well as growth options under revenue uncertainty. We revisit the conditions for dividend policy irrelevancy and the broader role of retained earnings and dividends. Retained earnings have a net positive impact on firm value in the presence of growth options, high external financing costs and low default risk. High levels of retained earnings enhance debt capacity but have a negative effect on equity value due to the likelihood of losing accumulated cash balances in case of default, unless offset by high external financing costs. Opposite directional effects of retained earnings on equity and debt create a U-shaped relation with firm value. The framework is extended to analyze management-shareholder conflicts, demonstrating that managers accumulate higher than optimal cash.     

Currency hedging for multinationals under liquidity constraints

This paper examines the impact of liquidity risk on the behavior of a risk-averse multinational firm (MNF) under exchange rate uncertainty in a two-period dynamic setting. The MNF has operations domiciled in the home country and in a foreign country, each of which produces a single homogeneous good to be sold in the home and foreign markets. To hedge the exchange rate risk, the MNF has access to one-period currency futures and option contracts in each period. The MNF is liquidity constrained in that it is obliged to terminate its risk management program in the second period whenever the net loss due to its first-period hedge position exceeds a predetermined threshold level. We show that the MNF optimally sells less (more) and produces more (less) in the foreign (home) country in response to the imposition of the liquidity constraint. We show further that the liquidity constrained MNF optimally uses the currency option contracts in the first period for hedging purposes in general, and opts for a long option position if its utility function is quadratic in particular.     

Investment timing and optimal capital structure under liquidity risk

Deterioration in debt market liquidity reduces debt values and affects firms' decisions. Considering such risk, we develop an investment timing model and obtain analytic solutions. We carry out a comprehensive analysis in optimal financing, default, and investment strategies, and stockholder–bondholder conflicts. Our model explains stylized facts and replicates empirical findings in credit spreads. We obtain six new insights for decision makers. We propose a ‘new trade-off theory’ for optimal capital structure, a new tax effect, and new explanations of ‘debt conservatism puzzle’ and ‘zero-leverage puzzle’. Failure in recognizing liquidity risk results in substantially over-leveraging, early bankruptcy or investment, overpriced options, and undervalued coupons and credit spreads. In addition, agency costs are surprisingly small for a high liquidity risk or a low project risk. Interestingly, the risk shifting incentive and debt overhang problem decrease with liquidity risk under moderate tax rates while they increase under high tax rates.     

Managing longevity risk under adverse selection: the influence of policyholder age and contract duration

In recent years, the rising life expectancy in almost all industrialized countries has led to an increasing demand by life insurers for possibilities to hedge longevity risk. Two of the most prominent alternative risk management instruments in this regard are the transfer of longevity risk to the capital market, e.g. through the purchase of mortality contingent bonds, and natural hedging, i.e. hedging longevity risk through portfolio composition. In this paper, we study the effectiveness of these risk management instruments under adverse selection, which here refers to the difference between annuitant mortality and the mortality of the population as a whole. Special emphasis is thereby placed on analyzing the impact of policyholders’ age at contract inception and contract duration on the effectiveness of risk management.     

Reinsurance contract design with adverse selection

ABSTRACT

In light of the richness of their structures in connection with practical implementation, we follow the seminal works in economics to use the principal–agent (multidimensional screening) models to study a monopolistic reinsurance market with adverse selection; instead of adopting the classical expected utility paradigm, the novelty of our present work is to model the risk assessment of each insurer (agent) by his value-at-risk at his own chosen risk tolerance level consistent with Solvency II. Under information asymmetry, the reinsurer (principal) aims to maximize his average profit by designing an optimal policy provision (menu) of ‘shirt-fit’ reinsurance contracts for every insurer from one of the two groups with hidden characteristics. Our results show that a quota-share component, on the top of simple stop-loss, is very crucial for mitigating asymmetric information from the insurers to the reinsurer.     

流动性过剩与农信社流动性不足

2007年以来,为缓解流动性过剩,控制货币信贷过快增长,央行频繁运用公开市场操作和上调存款准备金率等手段,加大货币回收力度.这虽然抑制了银行体系的流动性过剩,但对于作为弱势金融群体的农村信用社来说,紧缩货币政策实施所产生的累积效应对一些经济欠发达山区农信社的流动性管理带来了不利的影响,隐含的支付性风险不容忽视.     

保险市场逆向选择与顺向选择共存研究

保险市场存在着逆向选择。经典逆向选择模型认为,风险高的人会购买更多的保险,但大多数实证研究表明保险市场还存在顺向选择。本文认为,逆向选择和顺向选择虽然对立,但共存于保险市场,在此基础上构建保险市场均衡模型,并进行了仿真研究。     

Hedging and liquidity

This article develops a model for evaluating alternative hedgingstrategies for financially constrained firms. A key advantageof the model is the ability to capture the intertemporal effectsof hedging on the firm's financial situation. We characterizethe optimal hedge. A wide range of alternative hedging strategiescan be specified and the model allows us to determine in eachcase if the hedging strategy raises or lowers firms value andby how much. We show that hedging firm value, hedging cash flowfrom operations and hedging sales revenue are not optimal. Thearticle highlights the fact that every hedging strategy comespackaged with a borrowing strategy which requires careful consideration.     

Aggregate liquidity shortages, idiosyncratic liquidity smoothing and banking regulation

This paper develops a model of banking fragility driven by aggregate liquidity shortages. Inefficiencies arise from a failure of the interbank market to smooth the available liquidity in such a shortage. We find that a standard lender of last resort policy is ineffective in restoring efficiency as it leads to offsetting changes in the banks’ supply of liquidity. In contrast, subsidizing the purchase of assets from troubled banks increases welfare by improving the banks’ liquidity holdings. The first best, however, is achieved by redistributing existing liquidity from healthy to troubled banks in a crisis.     

Capital reallocation and liquidity

This paper shows that the amount of capital reallocation between firms is procyclical. In contrast, the benefits to capital reallocation appear countercyclical. We measure the amount of reallocation using data on flows of capital across firms and the benefits to capital reallocation using several measures of the cross-sectional dispersion of the productivity of capital. We then study a calibrated model economy where capital reallocation is costly and impute the cost of reallocation. We find that the cost of reallocation needs to be substantially countercyclical to be consistent with the observed joint cyclical properties of reallocation and productivity dispersion.     

Government intervention and adverse selection costs in foreign exchange markets

An important group of traders in the foreign exchange marketis governments who often adhere to a foreign exchange rate policyof occasional interventions with otherwise floating rates. Inthis article we provide a theoretical model and empirical evidencethat government foreign exchange interventions create significantadverse selection problems for dealers. In particular, our modelshows that the adverse selection component of the foreign exchangespread is positively related to the variance of unexpected interventionand that expected intervention has no impact on the spread.After controlling for inventory and order processing costs,we find that bid-ask spreads increase with U.S. dollar and Germandeutsche mark foreign exchange rate intervention during theperiod 1976-1994. Furthermore, when the intervention is decomposedinto expected and unexpected components, we find a statisticallyand economically significant increase in spreads with the varianceof unexpected intervention, while expected intervention hasno significant impact on spreads.     

国外流动性变化对我国流动性和利率的影响分析

随着市场对于美联储提前退出量化宽松政策预期的增强,研究国外流动性变化对我国流动性和利率变化的影响具有现实意义。该文通过实证分析发现,国外流动性变化对我国流动性变化的影响较大,而国外利率变化对我国利率变化的影响不明显。针对美联储量化宽松货币政策退出产生的影响,文章提出相关应对建议。     

Securitization without adverse selection: The case of CLOs

In this paper, we investigate whether securitization was associated with risky lending in the corporate loan market by examining the performance of individual loans held by collateralized loan obligations. We employ two different data sets that identify loan holdings for a large set of CLOs and find that adverse selection problems in corporate loan securitizations are less severe than commonly believed. Using a battery of performance tests, we find that loans securitized before 2005 performed no worse than comparable unsecuritized loans originated by the same bank. Even loans originated by the bank that acts as the CLO underwriter do not show under-performance relative to the rest of the CLO portfolio. While some evidence exists of under-performance for securitized loans originated between 2005 and 2007, it is not consistent across samples, performance measures, and horizons. Overall, we argue that the securitization of corporate loans is fundamentally different from securitization of other assets classes because securitized loans are fractions of syndicated loans. Therefore, mechanisms used to align incentives in a lending syndicate are likely to reduce adverse selection in the choice of CLO collateral.     

Global liquidity trap

How should monetary policy respond to a “global liquidity trap,” where the two countries may fall into a liquidity trap simultaneously? Using a two-country New Open Economy Macroeconomics model, we first characterize optimal monetary policy, and show that the optimal rate of inflation in one country is affected by whether or not the other country is in a liquidity trap. We next examine how well the optimal monetary policy is approximated by relatively simple monetary policy rules. The interest-rate rule targeting the producer price index performs well in this respect.     

Asymmetric information,adverse selection,and the pricing of CMBS

We demonstrate that asymmetric information between sellers (loan originators) and purchasers (investors and securities issuers) of commercial mortgages gives rise to a standard lemons problem, whereby portfolio lenders use private information to liquidate lower quality loans in commercial mortgage-backed securities (CMBS) markets. Conduit lenders, who originate loans for direct sale into securitization markets, mitigate problems of asymmetric information and adverse selection in loan sales. Our theory provides an explanation for the pricing puzzle observed in CMBS markets, whereby conduit CMBS loans are priced higher than portfolio loans, despite widespread belief that conduit loans are originated at lower quality. Consistent with theoretical predictions of a lemons discount, our empirical analysis of 141 CMBS deals and 16,760 CMBS loans shows that, after controlling for observable determinants of loan pricing, conduit loans enjoyed a 34 basis points pricing advantage over portfolio loans in the CMBS market.     

Consumer risk perceptions and information in insurance markets with adverse selection

Standard models of adverse selection in insurance markets assume policyholders know their loss distributions. This study examines the nature of equilibrium and the equilibrium value of information in competitive insurance markets where consumers lack complete information regarding their loss probabilities. We show that additional private information is privately and socially valuable. When the equilibrium policies separate types, policyholders can deduce the underlying probabilities from the contracts, so it is information on risk type, rather than loss probability per se, that is valuable. We show that the equilibrium is “as if” policyholders were endowed with complete knowledge if, and only if, information is noiseless and costless. If information is noisy, the equilibrium depends on policyholders' prior beliefs and the amount of noise in the information they acquire.     

Order-to-trade ratios and market liquidity

We study the impact on market liquidity of the introduction of a penalty for high order-to-trade ratios (OTRs), implemented by the Italian Stock Exchange to curtail high-frequency quote submission. We find that the fee is associated with a collapse in the quoted depth of the stocks that make up the bulk of trading in Italian equities and with an increase in price impacts of trading across the treated stocks. Spreads do not change, however. Stocks from a pan-European control sample show no such liquidity changes. Thus, the Italian OTR fee had the effect of making Italian stocks markets more shallow and less resilient. Large stocks are more severely affected than midcaps. We also find evidence of a limited decrease in turnover. Consolidated liquidity, constructed by aggregating across all electronic trading venues for these stocks, decreases just like that on the main exchange. Thus, liquidity was not simply diverted from the main exchange, it was reduced in aggregate.