供应链中甄别契约设计与信息共享激励

针对供应链中上下游企业的委托-代理问题,委托人可以设计出某种甄别契约以区分不同类型的代理人在不同的市场需求状况下的努力程度。在完全信息的条件下,委托人采取固定佣金方案及承担全部风险为最优选择。在信息不完全的条件下,若代理人为风险规避者则委托人只承担部分销售风险但需付出额外的风险补偿成本,若代理人为风险中性者则委托人不需付出额外的风险补偿成本。     

Risk,uncertainty and monetary policy

The VIX, the stock market option-based implied volatility, strongly co-moves with measures of the monetary policy stance. When decomposing the VIX into two components, a proxy for risk aversion and expected stock market volatility (“uncertainty”), we find that a lax monetary policy decreases both risk aversion and uncertainty, with the former effect being stronger. The result holds in a structural vector autoregressive framework, controlling for business cycle movements and using a variety of identification schemes for the vector autoregression in general and monetary policy shocks in particular. The effect of monetary policy on risk aversion is also apparent in regressions using high frequency data.     

饭店并购的财务问题及风险规避

并购是现代饭店常见的一种资本运作,能有效地实现饭店的快速扩张。并购能够提高饭店的规模经济效率,降低交易费用,使饭店多元化发展。但饭店在并购中会出现并购目标饭店价值评估、并购饭店的支付方式、并购饭店的融资等一系列的财务问题。正确认识饭店并购的价值评估风险、流动性风险、融资风险和汇率风险等财务风险并进行合理规避十分重要。     

Myopic Loss Aversion in Brazilian Open Retirement Funds

ABSTRACT

This paper analyzes the relationship between withdrawals from Brazilian open retirement funds, portfolio composition (fixed income or equity) and frequency of statement sending (monthly, quarterly, semiannually or annually). Our results indicate that equity retirement plans present a lower withdrawal index when compared to that of fixed income plans. Furthermore, the higher the statement sending frequency, the lower the withdrawals from open retirement plans. However, withdrawals from equity retirement plans tend to increase when statements are sent to investors more frequently. These phenomena can be explained by behaviorist theories, such as the concept of myopic loss aversion. In a context where loss aversion is present, the more frequently the investor evaluates his or her portfolio, or the shorter the investment horizon, the less attractive he or she will find investment in assets with a high rate of return and risk, such as equities. This behavior occurs not only regarding short-term investments, but also traditional long-term assets such as equity retirement plans.

RESUMEN. Este estudio analiza la relación existente entre las retiradas de los fondos abiertos de jubilación brasileños, la composición de la cartera (ingreso fijo o patrimonio), y la frecuencia del envío de estados financieros (mensual, trimestral, semestral o anualmente). Nuestros resultados indican que los planes de jubilación patrimonial tienen un índice de retirada menor, en comparación con los planes de ingreso fijo. Además, cuanto mayor la frecuencia de los estados financieros, menor es la retirada de los planes abiertos de jubilación. Sin embargo, las retiradas de los planes de jubilación patrimoniales tienden a aumentar cuando los estados se envían a los inversores con más frecuencia. Este fenómeno puede explicarse con las teorías comportamentales, tales como el concepto de la aversión miope a la pérdida. En un contexto donde la aversión a la pérdida es una realidad, cuanto mayor la frecuencia con que el inversor pueda evaluar su carera, o menor el horizonte de inversión, menos atractivas considerará él las inversiones en activos con un alto retorno y riesgo, tal como las acciones. Este comportamiento ocurre no sólo en las inversiones a corto plazo, sino también en los activos a largo plazo, como los planes de jubilación patrimoniales.

RESUMO. Este artigo analisa a relação entre as retiradas dos fundos abertos de aposentadoria brasileiros, a composição da carteira (renda fixa ou ações) e a freqüência da remessa de extratos (mensal, trimestral ou semestral). Nossos resultados indicam que os planos de aposentadoria que aplicam em ações apresentam um índice de retirada menor em comparação com os planos de renda fixa. Além disso, quanto maior a freqüência de remessa de extratos, menores as retiradas dos planos abertos de aposentadoria. Entretanto, as retiradas dos planos de aposentadoria que aplicam em ações tendem a aumentar quando o extrato é enviado aos investidores commais freqüência. Esses fenômenos podem ser explicados por teorias behavioristas, como o conceito de aversão míope à perda. Num contexto onde a aversão à perda esteja presente, quanto maior a freqüência com que o investidor avalia a sua carteira, ou quanto menor o horizonte do investimento, menos atraente ele achará o investimento em ativos com alto retorno e risco, como ações. Esse comportamento ocorre não apenas em investimentos a curto prazo, mas também nos ativos tradicionais de longo prazo como os planos de aposentadoria com aplicação em ações.     

企业年金投资的风险及其规避

投资运营是企业年金保值增值的关键环节,而有投资必有风险。本文从规避企业年金投资风险的角度,将企业年金投资风险分为三个层次：宏观经济变动引起的风险;企业年金在市场运营中产生的风险;企业年金投资运作主体引起的风险。引起投资风险的因素不同,则控制风险的措施不同。在风险识别的基础上,以创新理论为基础,从制度创新与技术创新两方面探讨了规避年金投资风险,获取较高、稳定收益的措施。     

Attitude toward imprecise information

This paper presents an axiomatic model of decision making under uncertainty which incorporates objective but imprecise information. Information is assumed to take the form of a probability–possibility set, that is, a set P of probability measures on the state space. The decision maker is told that the true probability law lies in P and is assumed to rank pairs of the form (P,f) where f is an act mapping states into outcomes. The key representation result delivers maxmin expected utility (MEU) where the min operator ranges over a set of probability priors—just as in the MEU representation result of Gilboa and Schmeidler [Maxmin expected utility with a non-unique prior, J. Math. Econ. 18 (1989) 141–153]. However, unlike the MEU representation, the representation here also delivers a mapping, , which links the probability–possibility set, describing the available information, to the set of revealed priors. The mapping is shown to represent the decision maker's attitude to imprecise information: under our axioms, the set of representation priors is constituted as a selection from the probability–possibility set. This allows both expected utility when the selected set is a singleton and extreme pessimism when the selected set is the same as the probability–possibility set, i.e., is the identity mapping. We define a notion of comparative imprecision aversion and show it is characterized by inclusion of the sets of revealed probability distributions, irrespective of the utility functions that capture risk attitude. We also identify an explicit attitude toward imprecision that underlies usual hedging axioms. Finally, we characterize, under extra axioms, a more specific functional form, in which the set of selected probability distributions is obtained by (i) solving for the “mean value” of the probability–possibility set, and (ii) shrinking the probability–possibility set toward the mean value to a degree determined by preferences.     

Are more risk averse agents more optimistic? Insights from a rational expectations model

We analyse a model of partially revealing, rational expectations equilibrium with diverse information, endogenous beliefs formation and uncertain distribution of risk aversion. More risk averse agents are then more optimistic. Such a positive correlation is important for collective decision analysis.     

中国股票市场波动非对称性的行为金融学解释

本文采用EGARCH与TARCH模型,以2003年6月30日至2008年6月27日的上证综指和深证综指日收益率为研究样本,对中国股票市场价格波动的非对称效应进行了检验,证实了中国股票市场存在对信息反应的不平衡,即:"利空消息"对股票价格的冲击大于"利多消息"对股票价格的冲击。鉴于国内研究对这种不对称的解释仅限于宏观层面,本文基于行为金融学理论,从投资者非理性行为出发,研究得出投资者的损失厌恶与反应过度的认知偏差是导致其对"利空消息"反应过度的根本原因。     

基于零售商风险厌恶的供应链管理

考虑由一个供应商和一个零售商组成的二级供应链,在零售商风险中性和风险厌恶的条件下,分别研究了三种不同契约下零售商的最优订单问题,得到零售商风险厌恶时的最优订单量要小于零售商风险中性时的最优订单量,最后给出研究结论及管理学意义。     

Ross risk vulnerability for introductions and changes in background risk

We present two theorems that provide necessary and sufficient conditions for an expected utility maximizer to become more risk averse in the sense of Ross with respect to bearing a foreground risk after the introduction of any independent fair or unfair additive background risk. We call these decision makers Ross risk vulnerable, and show that Ross decreasing absolute risk aversion and Ross decreasing absolute prudence are jointly sufficient for Ross risk vulnerability. Restrictions on utility necessary and sufficient for Ross risk vulnerability with respect to stochastic dominance deteriorations of an existing background risk are also presented. Our analysis concludes with applications of Ross risk vulnerability.