Hydro-economic Modeling in River Basin Management: Implications and Applications for the European Water Framework Directive

Economic ideas and processes are becoming increasingly integrated with more traditional engineering and hydrologic models of water management problems. Combining economic management concepts and performance indicators with an engineering-level of understanding of a hydrologic system can provide results and insights more directly relevant for water management decisions and policies. When such models are developed and used with involvement of stakeholders, they can become a basis for shared understanding of water problems as a foundation for negotiated management and policy solutions. When implemented with optimization software, integrated hydro-economic models also can suggest promising innovative solutions for policy-makers to consider. Their applications to river basin management problems are reviewed. Economic and integrated economic-engineering-hydrologic modeling is then discussed in the context of the evolving European Water Framework Directive. Relevant items are cost recovery and water pricing, cost-effectiveness of water management measures, and public participation in decision processes.     

Preliminary Assessment of Contaminants in Soft Sediments of the Detroit River

Soft sediments from the Detroit River were analyzed for the USEPA priority pollutants to generally characterize contaminant distribution. Forty-three were detected. Highest heavy metal concentrations were found in the Trenton Channel and immediately downstream of Grosse Ile. They ranged from an area mean (N = 2) of 0.19 mg/kg mercury to 338.7 mg/kg zinc (dry weight). Polynuclear aromatic hydrocarbons ranged from 0.1 mg/kg to 38.8 mg/kg (mean, N = 2) with the highest levels near Grosse Ile. PCBs ranged from 0.015 mg/kg to 1.7 mg/kg (mean, N = 2). Organochlorine pesticides were not detected except for a trace of heptachlor in one sample. Sediment contamination in the Detroit River is widespread with higher concentrations on the U.S. side downstream of the Rouge River and in the Trenton Channel. The significance of these in-place pollutants to biota and as a source to Lake Erie is still unknown.     

Baseline assessment of metals and hydrocarbons in the sediments of Lake Mulwala, Australia

An assessment of hydrocarbon and metal/metalloids (arsenic, cadmium, copper, lead, mercury, selenium, zinc) contamination in sediments from Lake Mulwala, Australia, was undertaken. The objectives of the study were: (i) to determine the extent of contamination in the lake sediments, compared to Australian and international sediment quality guidelines, and (ii) to attempt to identify the contaminant sources to the lake. With the exception of a few samples containing elevated levels of arsenic and/or mercury, the levels of all contaminants in the sediment samples taken from the lake were below the ‘lower trigger’ of the Australian Sediment Quality Guidelines that would warrant further investigation. High molecular weight hydrocarbons (up to 700 mg kg⁻¹) were found in most sediment samples. Non‐metric statistical analysis indicated that the contaminant distribution was different in different parts of the lake, with the lowest concentrations generally found at the influent to the lake. No definitive source(s) of contamination could be identified for either metalloids or hydrocarbons.     

Real Estate Valuation Models: Lender and Equity Investor Criteria

The use of valuation models that focus on lender criteria has been growing in the appraisal field. In the rush to build lender criteria into real estate valuation models, equity investor criteria, expectations, and requirements occasionally have been ignored. The specific criteria considered in this paper are the loan-to-value ratio and the debt coverage ratio for lenders and the equity dividend rate for equity investors. Each of these three criteria may be a binding constraint on value.
Graphical analysis provides a framework within which major real estate valuation models (i.e., Ellwood, McLaughlin, Gettel, Lusht-Zerbst, and Steele) are compared. A new valuation model (i.e., the Cannaday-Colwell model) is developed which utilizes the equity dividend rate.
The three definitional models (i.e., McLaughlin, Gettel, and Steele) are found to be relevant only by mere coincidence. Each of these models simultaneously considers two of the three key criteria, completely eliminating the possibility of consideration of anything else; i.e., the models become tautological.
It is shown that the discounted cash flow based models (i.e., Ellwood, Lusht-Zerbst, and Cannaday-Colwell) each tell one-third of the story. One of these models will be relevant depending upon whether the binding constraint is the maximum loan-to-value ratio, the minimum debt coverage ratio, or the minimum equity dividend rate. The relevant model is the one that yields the lowest value estimate of the three.     

新《公司法》的新看点

2006年1月1日,新《公司法》正式实施.《公司法》作了许多修改以解决公司治理方面存在的突出问题,完善公司治理.一直为业界所诟病的内部人控制和关联交易等将会大大减少,中小股东和债权人的利益将会得到有效保护.在新〈公司法〉的指引下,中国公司治理显露出新的走向.     

Manipulating uncertainty

Uncertainty about the distributional incidence of policy reforms may, if it impinges selectively on particular subsets of voters, alter the direction of the majority vote. This possibility should be a matter of special concern when subject to potential manipulation by a purposeful agent such as a Leviathan-like bureaucracy. This paper discusses a constitutional defense against such prospect. This paper was prepared for a conference on “Constitutional Status Quo and Prospects for Change” held at George Mason University in April, 1994. I am grateful to participants in that conference and to my colleagues at Nova, especially to Mário Páscoa, for their comments and criticisms. I also benefited from comments of an anonymous referee. Responsibility for errors remains with me.     

EARNINGS EXPECTATIONS, FIRM SIZE, AND THE INFORMATIVENESS OF STOCK PRICES

The notion that prices impound a wide array of information, including market expectations, has led to earnings forecast models conditioned on prices. Yet, presumably, analysts' forecasts capture both public information and certain private information not previously impounded in prices. Accordingly, price-based models are seemingly an inefficient, and less effective, source of expecta-tions. This article investigates this hypothesis using financial analysts', price-based, and naive forecasts. Results indicate that analysts' forecasts (1) are at least as accurate as price-based and naive models, and (2) yield better expectations for market tests relating returns and earnings. These inferences are robust across different information environments. The evidence suggests that analysts either possess private information or are more effective information processors, or both.     

A rational foundation for wishful exchange rate forecasts

Professor Takatoshi Ito in a recent American Economic Review paper documents that exporters and importers have biased exchange rate forecasts and the biases are in opposite directions. At first glance, it is difficult to provide a rational foundation for such behavior. Professor Ito hypothesizes that these forecasts are the result of wishful expectations. However, if forecasts are stochastic, then minimization of a quadratic loss function results in a rational hedge applied to either $/¥ or ¥/$. The different perspectives of importers and exporters determines which form is hedged and determines the direction of the bias.