数值地形图的生成及其水文地貌特征评价

数值地形图(DEM)是利用地理信息系统(GIS)进行流域水文模拟的基础, 其精度直接影响模拟结果在没有现成的数值地形图时, 应用人员往往利用传统的地形图来生成它. 本文分别采用Arc/Info地理信息系统软件提供的哈奇逊法和不规则三角网五次插值法, 对一个实验流域的高程取样点进行插值, 生成了4种不同的数值地形图, 从凹洼分布、流域界定、河网提取、地面坡度和地形指数、以及地面径流汇成等方面, 对它们的水文地貌精度进行了比较. 结果表明, 两种方法都能生成由高程点群所反映的地形, 然而由于哈奇逊法能够结合流域的河网结构及其具有物理基础的水文地貌加强法来处理凹洼问题, 因此大大地提高了其所生成的流域数值地形图水文地貌特征精度.     

A Comparison of Cost of Equity Estimates of Local and Global CAPMs

Cost of equity estimates are compared for three pricing models: the traditional local CAPM, the single (market) factor global CAPM, and the two‐factor global CAPM, with both market and currency index factors. For 2989 US stocks, the average difference in the cost of equity estimates is about 48 basis points between the local CAPM and the single‐factor global CAPM, and is about 61 basis points between the two global models. For 70 developed‐market ADRs, the corresponding average differences are 76 and 47 basis points, respectively. For 48 emerging‐market ADRs, the corresponding average differences are 57 and 70 basis points.     

GOVERNMENT POLICIES AND AGRICULTURAL SUPPLY RESPONSE: PADDY IN SRI LANKA

An aggregate analysis of supply response in the paddy (rice) sector of Sri Lanka during 1952-87 is conducted to identify the impact of pricing policy, irrigation programmes, institutional credit and concessional sales on area, yield and overall supply. The focus of the estimation procedure is the selection of an appropriate functional form for regressions and on the price variable that best represents the price to which producers respond in making area and yield decisions. In the case of both area and yield, the econometric criteria favour the acceptance of log-linear equations with the ratio of the guaranteed price of paddy to fertiliser price. On the basis of overall supply elasticity estimates, it is concluded that while pricing policy, irrigation programmes and institutional credit provide incentives to the expansion of paddy production, concessional sales of rice act as a disincentive.     

Polynomial approximations in cross-sectional models

The time-series distributed lag techniques of econometrics can be usefully applied to cross-sectional, spatial and cross-section time-series situations. The application is perfectly natural in cross-section, time-series models when regression coefficients evolve systematically as the cross-section grouping variable changes. The evolution of such coefficients lends itself to polynomial approximation or more general smoothing restrictions. These ideas are not new, Gersovitz and McKinnon (1978) and Trivedi and Lee (1981) providing two of the earliest applications of cross-equation smoothing techniques. However, their applications were in the context of coefficient variation due to seasonal changes and this may account for the non-diffusion of these techniques. The approach here is illustrated in the context of age-specific household formation equations based on census data, using Almon polynomials when the regression coefficients vary systematically by age group. A second application is provided, using spatial data, explaining the incidence of crime, by region; using polynomial and geometric smoothing to model distance declining regional effects.     

Operating efficiency of Canadian banks

This article assesses Canadian banks' ability to realize scale economies and cost complementarities in joint production. The Canadian banking system, with its 10 or so large banks and 50 smaller ones, offers a good database for a study of efficiency, especially since previous work suggests that the system's concentration has had little impact on system competitiveness. This article estimates a system of cost and cost share equations using Zellner's iterative seemingly unrelated regression technique, then evaluates scale economies and cost complementarities from the estimated cost functions' first and second partial derivatives. The article compares a model that classifies deposits as inputs with another that classifies them as outputs. The empirical findings indicate that deposits are better modelled as outputs than inputs; that Canadian banks organize to exhaust available sources of scale economies and economies in joint production; and that conclusions regarding scale economies and cost complementarities differ importantly according to whether deposits are modelled as inputs or as outputs.     

HEDGING INTEREST RATE RISK UNDER TERM STRUCTURE EFFECTS: AN APPLICATION TO FINANCIAL INSTITUTIONS

In this paper we investigate the use of the structured full rank model for hedging the balance sheet of a financial institution. Simulation results suggest that the optimal hedge is insensitive to changes in parameter estimates. In addition, we hedge a portfolio of Treasury bills using both the full information covariance matrix and the structured covariance matrix. We then contrast these results with those obtained from a duration-based model. Empirical results suggest that the structured full rank model is generally more effective in hedging applications than either the full information model or duration-based model.     

Selected individual differences and collegians' ethical beliefs

This paper develops twenty hypotheses concerning the relationships among selected individual differences variables (locus of control, delay of gratification, gender, and race) and five different ethical beliefs. The results of a study of collegians provide support for seventeen out of twenty research hypotheses. As predicted, locus of control, delay of gratification, and race are related to ethical beliefs. Also as predicted, gender is not related to ethical beliefs. Michael K. McCuddy, Professor of Human Resource Management at Valparaiso University, has conducted research on a variety of organizational topics. His work has been published in the Academy of Management Journal, Journal of Applied Psychology, Journal of Organizational Behavior Management, The Health Care Supervisor, and Management Accounting. His current interests involve academic ethics and subsequent career behavior, organizational morality and organizational success, and ethics in the management accounting profession. Barbara L. Peery, Adjunct Professor of Management at Virginia Commonwealth University, teaches courses in Entrepreneurship and Human Resources Management. Her scholarly work has been published in the Journal of Small Business Management and the Journal of Private Enterprise. Her current research interests focus on the antecedents and consequences of academic ethics. She has co-directed or coordinated several consulting projects for agencies in the Commonwealth of Virginia, and has taught in Russia.