Black Education: Myths and Tragedies

This article explores elements of apologetics in conventional economics. It argues that much of the latter is apologetics in the form of the ideology or utopia of laissez-faire, and many of its representatives are apologists of the latter. The article first examines instances of unconditional laissez-faire apologetics and extreme apologists. Then it presents cases of qualified laissez-faire apologetics and moderate apologists. Lastly, it identifies some examples of laissez-faire non- and anti-apologetics and critics expressing discontent with apologetic economics. The article aims to contribute to a fuller understanding of the relationship between economics and social science overall and ideology, politics, and related non-scientific elements.     

The Hartwick Rule: Myths and Facts

We shed light on the Hartwick rule for capital accumulation and resource depletion by providing semantic clarifications and investigating the implications and relevance of this rule. We extend earlier results by establishing that the Hartwick rule does not indicate sustainability and does not require substitutability between man-made and naturalcapital. We use a new class of simple counterexamples (i) to obtain the novel finding that a negative value of net investments need not entail that utility is unsustainable, and (ii) to point out deficiencies in the literature.     

Volatility and VaR forecasting in the Madrid Stock Exchange

This paper provides an empirical study to assess the forecasting performance of a wide range of models for predicting volatility and VaR in the Madrid Stock Exchange. The models performance was measured by using different loss functions and criteria. The results show that FIAPARCH processes capture and forecast more accurately the dynamics of IBEX-35 returns volatility. It is also observed that assuming a heavy-tailed distribution does not improve models ability for predicting volatility. However, when the aim is forecasting VaR, we find evidence of that the Student’s t FIAPARCH outperforms the models it nests the lower the target quantile.      

最小平均VaR套期保值比率计算模型及实证研究

针对传统的套期保值模型只考虑最小化套期保值组合在到期日的价格风险,而且没有充分利用资产历史价格样本数据所提供的收益率信息的特点,本文提出了考虑套期保值期内不同期限价格风险的最小平均VaR套期保值比率计算模型。基于我国外汇市场及股票市场数据,本文对最小平均VaR套期保值模型进行了实证分析,并与常用的最小方差及最小VaR套期保值模型进行了对比,得出了最小平均VaR模型在套期保值过程中的效果要优于其他两种模型,能更有效地降低投资者提前终止套期保值可能面临额外风险的结论。     

Quick-service expenditure in Ireland: parametric vs. semiparametric analysis

The aim of this study is to identify the economic and socio-economic factors influencing Irish households' expenditure on quick-service meals, a particularly dynamic component of the foodservice industry, and to determine the extent to which these factors have changed over the course of the 1990s. Maximum likelihood estimation and semiparametric alternatives are considered with the conclusion that in this instance semiparametric techniques do not offer a viable alternative to maximum likelihood estimation of tobit models, even in the presence of heteroscedasticity and non-normality. The results revel that household income, place of residence, commuters and household size have significant and positive influences on quick-service expenditure. Older families, single households and married couples, together with homeowners, display reduced expenditure. The opportunity cost of time is positively related to quick-service expenditure, consistent with theory, while health knowledge has a negative impact on quick-service consumption.     

金融市场风险之测定工具——VaR法的原理及应用

市场风险是金融市场风险中最重要的一种风险,将其定量化分析,是当前银行、财务公司、公司管理人员、投资人及金融监管当局对评估和管理个别资产或资产组合的市场亟待解决的问题,VaR法是国外普遍采用的市场风险测定技术。     

我国期货价格风险管理研究——基于VaR方法与GARCH-t模型的视角

本文利用我国商品期货及金融期货2010年9月份合约数据采用VaR方法对其收益率序列的波动性进行了检验。研究结果发现:首先,应用GARCH-t模型的方法对期货商品的价格风险进行管理具有显著的有效性和适用性,特别是在95%的置信水平下对收益率波动性的拟合效果最佳,同时该方法对期货商品正收益率的拟合效果比负收益率更好。其次,我国股指期货正式推出后,收益率波动性较模拟交易时期显著变小,表明改进后的交易制度及政府监管等措施可能限制了市场上的过度投机行为。最后,农副产品期货的风险暴露程度比股指、金属和能源化工等期货品种要小。     

基于GARCH模型的证券投资基金VaR计算与实证研究

基于统计技术的度量金融市场风险值(Value at Risk,VaR)已成为测量市场风险的新标准和新方法。鉴此,如何高效、准确地进行VaR的计算将是问题所在。基于GARCH模型,讨论了对数收益率时间序列在正态、学生t和广义误差(GED)三种不同分布下的VaR计算方法,对样本基金的市场风险进行估计,并通过返回检验来检验模型的准确性。研究结果表明,基于GED分布的GARCH模型计算的VaR值最能真实地反映基金风险。     

More on parametric characterizations of risk aversion and prudence

Summary. This note provides an alternative proof for the equivalence of decreasing absolute prudence (DAP) in the expected utility framework and in a two-parametric approach where utility is a function of the mean and the standard deviation. In addition, we elucidate that the equivalence of DAP and the concavity of utility as a function of mean and variance, which was shown to hold for normally distributed stochastics in Lajeri and Nielsen [4], cannot be generalized. Received: November 27, 2000; revised version: November 26, 2001 Correspondence to: T. Eichner     

欧盟碳期货风险量化——基于GED-GARCH模型和VaR模型

以欧盟碳期货合约为研究对象,针对其反映的市场风险特点,采用GED-GARCH模型进行参数估计。结果显示:到期日的因素使得欧盟碳期货合约收益率序列的条件方差与历史信息之间存在联系;碳期货合约的到期日越久,其条件方差越依赖于历史信息,表明欧盟碳期货市场为弱式有效市场;欧盟碳期货合约收益率序列的波动会逐渐衰减,表明最终合约价格能够起到价格预示作用。再利用GARCH模型的参数估计结果,计算出不同置信水平下收益率序列的在险值,夯实实证研究结果。针对欧盟碳期货合约风险的量化研究表明,欧盟碳期货与碳现货的关系呈现出新兴市场的分割局面特征,进一步导致欧盟碳金融市场逐渐走向虚拟化。因此,在中国碳市场的建设中,应做到碳期货与碳现货交易相协调,做好碳金融市场上风险的量化和控制。     

Conditional volatility and correlations of weekly returns and the VaR analysis of 2008 stock market crash

Modelling of conditional volatilities and correlations across asset returns is an integral part of portfolio decision making and risk management. Over the past three decades there has been a trend towards increased asset return correlations across markets, a trend which has been accentuated during the recent financial crisis. We shall examine the nature of asset return correlations using weekly returns on futures markets and investigate the extent to which multivariate volatility models proposed in the literature can be used to formally characterize and quantify market risk. In particular, we ask how adequate these models are for modelling market risk at times of financial crisis. In doing so we consider a multivariate t version of the Gaussian dynamic conditional correlation (DCC) model proposed by Engle (2002), and show that the t-DCC model passes the usual diagnostic tests based on probability integral transforms, but fails the value at risk (VaR) based diagnostics when applied to the post 2007 period that includes the recent financial crisis.     

非公有资本与基础设施有效供给

由于基础设施供给属性上具有市场性和非市场性并存的特征,因而,它不仅仅是单纯非公有资本或单纯的政府活动就可以使其有效发展的,它通常需要二者的有机结合并相互采取多样化的所有制实现形式。鉴于我国的国情和非公有资本的现实状况,我们不能照搬国外非公有资本参与基础设施的方式或模式,但为了加快基础设施建设和提高基础设施投资、经营的效益,应当采取多种形式拓宽非公有资本进入基础设施的渠道。(一)鼓励非公有经济采取联合、联营、集资、入股等方式参与基础设施建设;(二)通过实行特许权招投标、选择项目法人的方式吸引民营资本进入;(三)盘活存量资产吸引民营资本;(四)通过资本置换方式吸引民营投资;(五)以项目捆绑组合方式吸引民营资本;(六)利用资源补偿方式吸引民营投资;(七)建立产业投资基金,聚集民间闲散资金;(八)项目资产证券化。     

Non Utility Power,Alternative Regulatory Regimes and Stranded Investment

The electric industry is experiencing increasing competition in generation encouraged by non utility generators and regulatory agencies. An electric utilitys problem of satisfying stochastic demand with either power purchased from non utility generators or with its own generators is examined. The utility is subject to either rate-of-return regulation, profit sharing or price caps. The level of profit at which sharing is triggered is shown to be endogenous to the utilitys problem. The paper demonstrates how the form of regulation affects purchases of non utility power and measures of stranded investment. Simulations highlight the tradeoff between allocative efficiency and recovery of stranded investment.     

用VaR度量与管理投资基金的市场风险

度量和管理我国证券投资基金的市场风险十分迫切.本文以上证基金指数代替具体投资基金的价格作为样本数据,分别采用δ-正态法和极值理论方法计算出了相应的风险价值VaR用以度量我国证券投资基金的市场风险,同时对投资基金市场风险的VaR度量进行了分析和有效性检验,最后,文章就VaR在投资基金的战略性资产配置、优化投资组合、控制基金投资风险、绩效评估和信息披露等方面的应用作了一些探讨.