We characterize when a convex risk measure associated to a law-invariant acceptance set in L$^∞$ can be extended to L$^p$, 1≤p<∞, preserving finiteness and continuity. This problem is strongly connected to the statistical robustness of the corresponding risk measures. Special attention is paid to concrete examples including risk measures based on expected utility, max-correlation risk measures, and distortion risk measures.
This study provides experimental evidence, using a large sample of 2894 individuals recruited via business media websites, about the impact of demographic attributes within entrepreneurial teams on funding decisions by external capital providers. In previous work the role of diversity with regard to personal characteristics within entrepreneurial teams, such as education, gender and nationality was not clear. Specifically, we focus on task-oriented (e.g., education, experience) and relations-oriented (e.g., age, nationality) dimensions of diversity. The participants of our experiment had to decide on providing early-stage funding to a team of start-up managers whereas the diversity of these teams varied across treatment groups. We find that task-oriented diversity is positively and significantly related to the willingness of respondents to provide capital. Interestingly, the same applies for relations-oriented diversity. This suggests social capital of an entrepreneurial team matters to a greater extent to funding decisions of external investors than the behavioral integration of the team's human capital. Entrepreneurial teams must therefore carefully balance the social costs of non-task-related diversity and the access to financial resources.
Puts and calls on S&P500 futures are bought and sold for various purposes including speculation, hedging and portfolio insurance. We investigate the rate of return from buying or selling these options from the start of options trading in 1985 until 2010. These rates of return are variable and depend upon the trading horizons, the level of the VIX volatility index, whether the options are in or out or near the money and whether the market is rallying or in a crash mode. We specifically study the 2007-9 stock market crash period and various bullish market periods. Our results show that while selling out-of-the-money options is generally profitable, it sometimes generates steep losses. Hence, speculators trying to take advantage of mispriced options are wise to utilize accurate prediction models, devise variable types of hedged strategies and be well capitalized to weather market storms and have strategies in place to deal with
them.
In Arrow’s seminal analysis of optimal risk bearing in which he introduced contingent claim securities, he assumed preferences were representable by a state independent Expected Utility function. Although the classic contingent claim setting assumes agents choose over contingent consumption vectors conditioned on a fixed set of probabilities, later work on information economics suggested that allowing probabilities to change across contingent claim spaces could be an interesting extension. However the set of axioms that are necessary and sufficient for the existence of an Expected Utility representation for the classic contingent claim space with a fixed set of probabilities does not ensure that this form utility extends across multiple contingent claim spaces. In this paper, we derive a set of axioms on preferences which are necessary and sufficient for the existence of an Expected Utility representation when probabilities change. We also consider the incremental axioms which are necessary and sufficient for Expected Utility preferences to extend to the classic lottery setting of von Neumann and Morgenstern, where agents choose not only over consumption vectors but also over probabilities vectors.
We propose a method to compute equilibria in dynamic models with several continuous state variables and occasionally binding constraints. These constraints induce non-differentiabilities in policy functions. We develop an interpolation technique that addresses this problem directly: It locates the non-differentiabilities and adds interpolation nodes there. To handle this flexible grid, it uses Delaunay interpolation, a simplicial interpolation technique. Hence, we call this method Adaptive Simplicial Interpolation (ASI). We embed ASI into a time iteration algorithm to compute recursive equilibria in an infinite horizon endowment economy where heterogeneous agents trade in a bond and a stock subject to various trading constraints. We show that this method computes equilibria accurately and outperforms other grid schemes by far.
Credit Default Swaps (CDS) spreads should reflect default risk of the underlying corporate debt. Actually, it has been recognized that CDS spread time series did not anticipate but only followed the increasing risk of default before the financial crisis. In principle, the network of correlations among CDS spread time series could at least display some form of structural change to be used as an early warning of systemic risk. Here we study a set of 176 CDS time series of financial institutions from 2002 to 2011. Networks are constructed in various ways, some of which display structural change at the onset of the credit crisis of 2008, but never before. By taking these networks as a proxy of interdependencies among financial institutions, we run stress-test based on Group DebtRank. Systemic risk before 2008 increases only when incorporating a macroeconomic indicator reflecting the potential losses of financial assets associated with house prices in the US. This approach indicates a promising way to detect systemic instabilities.
This paper seeks to inform about a feature of monetary policy that is largely overlooked, yet occupies a central role in modern monetary and financial systems, namely central bank collateral frameworks. Their importance can be understood by the observation that the money at the core of these systems, central bank money, is injected into the economy on terms, not defined in a market, but by the collateral frameworks and interest rate policies of central banks. Using the collateral framework of the Eurosystem as a basis of illustration and case study, the paper brings to light the functioning, reach, and impact of collateral frameworks. A theme that emerges is that collateral frameworks may have distortive effects on financial markets and the wider economy. They can, for example, bias the private provision of real liquidity and thereby also the allocation of resources in the economy as well as contribute to financial instability. Evidence is presented that the collateral framework in the euro area promotes risky and illiquid collateral and, more generally, impairs market forces and discipline. The paper also emphasizes the important role of ratings and government guarantees in the Eurosystem’s collateral framework.
We show that collateral plays an important role in the design of debt contracts, the provision of credit, and the incentives of lenders to monitor borrowers. Using a unique data set from a large bank containing timely assessments of collateral values, we find that the bank responded to a legal reform that exogenously reduced collateral values by increasing interest rates, tightening credit limits, and reducing the intensity of its monitoring of borrowers and collateral, spurring borrower delinquency on outstanding claims. We thus explain why banks are senior lenders and quantify the value of claimant priority.
