(In)Efficient Interbank Networks

We study the efficiency properties of the formation of an interbank network. Banks face a trade-off by establishing connections in the interbank market. On the one hand, banks improve the diversification of their liquidity risk and therefore can obtain a higher expected payoff. On the other hand, banks not sufficiently capitalized have risk-shifting incentives that expose them to the risk of bankruptcy. Connecting to such risky banks negatively affects expected payoff. We show that both the optimal and the decentralized networks are characterized by a core-periphery structure. The core is made of the safe banks, whereas the periphery is populated by the risky banks. Nevertheless, the two network structures coincide only if counterparty risk is sufficiently low. Otherwise, the decentralized network is underconnected as compared to the optimal one. Finally, we analyze mechanisms that can avoid the formation of inefficient interbank networks.     

Bank market power,asset liquidity and funding liquidity: International evidence

Our investigation of the association between bank market power and liquidity in 101 countries reveals that a bank's initial gains of market power lead to increases in bank liquidity, but does so at a diminishing rate. Beyond an empirically determined threshold, further increases in market power are inversely associated with bank liquidity. From a cross-sectional viewpoint, banks that lack market power hold more liquid assets and are net lenders in the interbank market. In contrast, dominant banks hold less liquid assets and are net interbank borrowers. For a given level of market power, ceteris paribus, developed nation banks hold less asset liquidity and obtain more interbank funding liquidity than their developing country peers. These results remain equally relevant during the 2007–2009 global financial crisis (GFC).     

Liquidity Coinsurance and Bank Capital

Banks can deal with their liquidity risk by holding liquid assets (self‐insurance), by participating in interbank markets (coinsurance), or by using flexible financing instruments, such as bank capital (risk sharing). We use a simple model to show that undiversifiable liquidity risk, that is, the liquidity risk that banks are unable to coinsure on interbank markets, represents an important risk factor affecting their capital structures. Banks facing higher undiversifiable liquidity risk hold more capital. We posit that, empirically, banks that are more exposed to undiversifiable liquidity risk are less active on interbank markets. Therefore, we test for the existence of a negative relationship between bank capital and interbank market activity and find support in a large sample of U.S. commercial banks.     

FX counterparty risk and trading activity in currency forward and futures markets

The Global Financial Crisis initiated a period of market turbulence and increased counterparty risk for financial institutions. Even though the Dodd–Frank Act is likely to exempt interbank foreign exchange trading from a central counterparty mandate, market participants have the option to trade currency futures on existing futures markets which standardize counterparty risks. Evidence for the period 2005–11 indicates that the market share of currency futures trading has grown relative to the pre-crisis period. This shift may be the result of a perceived increase in counterparty risk among banks, as well as changes in relative trading costs or changes in other institutional factors.     

融资流动性对商业银行资产配置行为的动态影响

使用14家上市银行2007~2013年季度数据建立面板向量自回归(PVAR)模型,运用脉冲响应函数分析融资流动性对银行资产配置行为的动态影响。研究结果表明：存款成本和银行间融资成本的上升,会激励银行增加风险资产,减少流动性储备,不利于银行防范结构性流动性风险;存款流失会削弱银行贷款扩张的动力,提升流动性偏好;同业融资依赖性的上升短期内可以改善银行资产的流动性,长期则会加大资金借短贷长的问题,为流动性危机埋下隐患。     

Modelling the emergence of the interbank networks

Interbank contagion has become a buzzword in the aftermath of the financial crisis that led to a series of shocks to the interbank market and to periods of pronounced market disruptions. However, little is known about how interbank networks are formed and about their sensitivity to changes in key bank parameters (for example, induced by common exogenous shocks or by regulatory initiatives). This paper aims to shed light on these issues by modelling endogenously the formation of interbank networks, which in turn allows for checking the sensitivity of interbank network structures and hence, their underlying contagion risk to changes in market-driven parameters as well as to changes in regulatory measures such as large exposures limits. The sequential network formation mechanism presented in the paper is based on a portfolio optimization model, whereby banks allocate their interbank exposures while balancing the return and risk of counterparty default risk and the placements are accepted taking into account funding diversification benefits. The model offers some interesting insights into how key parameters may affect interbank network structures and can be a valuable tool for analysing the impact of various regulatory policy measures relating to banks’ incentives to operate in the interbank market.     

Liquidity Crunch in the Interbank Market: Is it Credit or Liquidity Risk, or Both?

The interplay between liquidity and credit risks in the interbank market is analyzed. Banks are hit by idiosyncratic random liquidity shocks. The market may also be hit by bad news at a future date, implying the insolvency of some participants and creating a lemons problem; this may end up with a gridlock of the interbank market at that date. Anticipating such possible contingency, banks currently long of liquidity ask a liquidity premium for lending beyond a short maturity, as a compensation for the risk of being short of liquidity later and being forced to liquidate some illiquid assets. When such premium gets too high, banks currently short of liquidity prefer to borrow short term. The model is able to explain some stylized facts of the 2007–2009 liquidity crunch affecting the money market at the international level: (i) high spreads between interest rates at different maturities; (ii) “flight to overnight” in traded volumes; (iii) ineffectiveness of open market operations, leading the central banks to introduce some relevant innovations into their operational framework.     

Can banks default overnight? Modelling endogenous contagion on the O/N interbank market

We propose a new model of the liquidity-driven banking system focusing on overnight interbank loans. This significant branch of the interbank market is commonly neglected in the banking system modelling and systemic risk analysis. We construct a model where banks are allowed to use both the interbank and the securities markets to manage their liquidity demand and supply as driven by prudential requirements in a volatile environment. The network of interbank loans is dynamic and simulated every day. We show how the intrasystem cash fluctuations alone, without any external shocks, may lead to systemic defaults, and what may be a symptom of the self-organized criticality of the system. We also analyze the impact of different prudential regulations and market conditions on the interbank market resilience. We confirm that the central bank’s asset purchase programmes, limiting the declines in government bond prices, can successfully stabilize banks’ liquidity demands. The model can be used to analyze the interbank market impact of macroprudential tools.     

货币政策对银行间市场流动性影响效应的实证研究及启示

银行间货币市场是央行实施货币政策的重要平台，研究货币政策对银行间市场流动性的影响对于完善商业银行日常流动性管理具有重要意义。文章在设定银行间市场流动性测度指标与梳理货币政策工具对市场流动性的影响机制的基础上，分别使用事件分析法和时间序列模型对不同政策工具的影响效应进行实证分析，得出相关分析结论，并总结其对于完善商业银行日常流动性管理的启示。     

Interbank liquidity risk transmission to large emerging markets in crisis periods

In this paper, we conduct two investigations regarding funding liquidity risk in large emerging economies: Brazil, Russia, India, China, and South Africa — BRICS. In the first, we track the relevance of monetary policy decisions originating in developed economies for interbank funding liquidity risk in BRICS economies during crisis periods by applying a time-varying parameter model in a Bayesian framework. The results indicate weak associations between interbank credit market and US monetary policy and market conditions. In contrast, the Federal Reserve's National Financial Conditions Index (NFCI) — a representative of the health of both real and financial sectors in the US — matters more. The temporal patterns of the results imply that key central banking decisions precede or coincide with low degrees of associations. In the second, we examine whether interbank credit crunch exerts an influence on market liquidity risk in BRICS economies using a Granger causality approach. The results reveal that interbank credit crunch depresses market liquidity in the corresponding domestic market and that the state of fear and credit market conditions in the US exert some influence in this regard. Overall, our findings hint at judicious market intervention and liquidity management by BRICS central banks.     

Interbank market liquidity and central bank intervention

We develop a simple model of the interbank market where banks trade a long term, safe asset. When there is a lack of opportunities for banks to hedge idiosyncratic and aggregate liquidity shocks, the interbank market is characterized by excessive price volatility. In such a situation, a central bank can implement the constrained efficient allocation by using open market operations to fix the short term interest rate. It can be constrained efficient for banks to hoard liquidity and stop trading with each other if there is sufficient uncertainty about aggregate liquidity demand compared to idiosyncratic liquidity demand.     

Optimal liquidity management and bail-out policy in the banking industry

We characterize the profit-maximizing reserves of a commercial bank, and the generated probability of a liquidity crisis, as a function of the penalty imposed by the Central Bank, the probability of depositors' liquidity needs, and the return on outside investment opportunities. We demonstrate that banks do not fully internalize the social cost associated with the bail-out policy if the liquidity needs of individuals are correlated, and that competitive interbank markets will induce banks to raise their reserves under reasonable conditions. The marginal benefits from an interbank market decrease as the correlation between the liquidity shocks of banks increases.     

Money and liquidity in financial markets

We argue that there is a connection between the interbank market for liquidity and the broader financial markets, which has its basis in demand for liquidity by banks. Tightness in the market for liquidity leads banks to engage in what we term “liquidity pull-back,” which involves selling financial assets either by banks directly or by levered investors. Empirical tests on the stock market are supportive. Tighter interbank markets are associated with relatively more volume in more liquid stocks; selling pressure, especially in more liquid stocks; and transitory negative returns. We control for market-wide uncertainty and in the process also contribute to the literature on portfolio rebalancing. Our general point is that money matters in financial markets.     

Network reactions to banking regulations

Optimal regulatory restrictions on banks have to solve a delicate balance. Tighter regulations reduce the likelihood of banks’ distress. Looser regulations foster the allocation of funds toward productive investments. With multiple banks, optimal regulation becomes even more challenging. Banks form partnerships in the interbank lending market in order to face liquidity needs and to meet investment possibilities. We show that the interbank network can suddenly collapse when regulations are pushed beyond a critical level, with a discontinuous increase in systemic risk as the cross-insurance of banks collapses.     

Lending relationships in the interbank market

We use a unique dataset to show that relationships are an important determinant of banks' ability to access interbank market liquidity. More precisely, we find that: (i) banks with a larger reserve imbalance are more likely to borrow funds from banks with whom they have a relationship, and to pay a lower interest rate than otherwise; (ii) smaller banks and banks with more non-performing loans tend to have limited access to international markets, and rely more on relationships; (iii) relationships are established between banks with less correlated liquidity shocks. These results suggest that relationships allow banks to insure liquidity risk in the presence of market frictions such as transaction and information costs. Our analysis explicitly controls for the endogeneity of bank relationships.     

Using Interest Rate Derivative Prices to Estimate LIBOR-OIS Spread Dynamics and Systemic Funding Liquidity Shock Probabilities

Following the bankruptcy of Lehman Brothers in mid-September 2008, there were severe disruptions in international money markets and banks reportedly faced severe liquidity shocks in particular US dollar funding shortages, prompting central banks around the world to adopt unprecedented policy measures to supply funds to the banks. A better understanding of the forward-looking information content about funding liquidity risk in interest rate derivative prices is therefore necessary to gauge pressures building surrounding systemic liquidity. Using the market prices of the US dollar LIBOR-overnight index swap spread, we estimate the probability of the systemic funding liquidity shock during the crisis period, which deviated from zero on 17 September 2008 to a significant level. This provided an early warning signal of the systemic liquidity shock on 29 September 2008 when the interbank market was totally paralysed.     

Liquidity Risk,Bank Networks,and the Value of Joining the Federal Reserve System

Reducing systemic liquidity risk related to seasonal loan demand was one reason for founding the Federal Reserve System. Nevertheless, less than 8% of state‐chartered banks joined the Fed in its first decade. Banks facing high liquidity risk from seasonal loan demand were more likely to join the Fed in its first decade. We also find evidence consistent with the notion that banks could obtain some indirect access to the discount window through interbank transfers. Some banks apparently joined the Fed to pass through discount window liquidity to other banks via the interbank network.  Joining the Fed increased member banks’ lending.     

银行间市场流动性与金融风险救助机制研究

文章从我国银行间市场结构特征出发,分析了近年来银行间市场利率和流动性大 幅波动的内在机理与原因。研究认为,塔形市场交易结构下,银行间市场存在流动性风险易聚 集不易分散的缺陷,且难以依靠“有形之手”得到弥补。文章结合塔形市场结构的特点建立矩 阵分析法,对40家金融机构资产负债表进行实证分析。结论印证了理论分析,即塔形市场交易 结构下风险冲击影响时间更长,且央行流动性救助效果降低,但流动性救助机制能降低风险对 中小型地方法人金融机构的冲击。因此,有必要建立流动性风险救助机制,弥补银行间市场客 观存在的缺陷,增强中小型地方法人金融机构抵御银行间市场流动性风险冲击的能力。     

Quantifying preferential trading in the e-MID interbank market

Interbank markets allow credit institutions to exchange capital for purposes of liquidity management. These markets are among the most liquid markets in the financial system. However, liquidity of interbank markets dropped during the 2007–2008 financial crisis, and such a lack of liquidity influenced the entire economic system. In this paper, we analyse transaction data from the e-MID market which is the only electronic interbank market in the Euro Area and US, over a period of 11 years (1999–2009). We adapt a method developed to detect statistically validated links in a network, in order to reveal preferential trading in a directed network. Preferential trading between banks is detected by comparing empirically observed trading relationships with a null hypothesis that assumes random trading among banks doing a heterogeneous number of transactions. Preferential trading patterns are revealed at time windows of 3-maintenance periods. We show that preferential trading is observed throughout the whole period of analysis and that the number of preferential trading links does not show any significant trend in time, in spite of a decreasing trend in the number of pairs of banks making transactions. We observe that preferential trading connections typically involve large trading volumes. During the crisis, we also observe that transactions occurring between banks with a preferential connection occur at larger interest rates than the complement set—an effect that is not observed before the crisis.     

我国银行间市场资金面影响因素的探讨——兼对当前市场流动性状况的分析与展望

梳理银行间市场资金面的影响因素,对于分析市场资金面的供求关系,央行评估货币政策执行效果,以及金融机构进行资产组合配置都有积极作用。文章从货币政策、商业银行存贷款增量、央行外汇占款、税收因素等多个角度,梳理了影响我国银行间市场资金面的八项因素,并在此基础上分析了今年5月份以来银行间市场资金面快速趋紧的成因。三季度,受CPI冲高回落、重申人民币汇改以及大型商业银行流动性状况好转等因素影响,银行间市场资金面紧张的格局将逐步改善。