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61.
Erik Benrud 《Journal of Economics and Finance》2007,31(2):143-165
The demand for and supply of analysts’ opinions in this model yield an equilibrium that demonstrates how the information content
of the opinions reacts to changes in exogenous parameters. The model also shows how changes in the parameters make analysts’
opinions more or less dispersed; for example, a decline in investor risk aversion, a decrease in market volatility, and an
increase in information costs can lead to analysts’ opinions becoming more similar. Recognizing how exogenous factors can
affect the supply and demand of analysts’ opinions gives additional insights into questions concerning what may appear to
be herd behavior by analysts and also the relationship between forecast dispersion and information content. (JEL: G29, C71) 相似文献
62.
63.
Ohne Zusammenfassung
Dipl.-Ing. (univ.) Michael Belau ist Director und Head of Rental Management
Dipl.-Wirtschaftsing. (FH) Michael Schildger ist Vice President und Head of Finance
Dr. Verena Sturm ist Manager Corporate Real Estate Services 相似文献
64.
Gabrielle Demange 《Economic Theory》2002,20(1):1-27
Summary. This paper defines and studies optimality in a dynamic stochastic economy with finitely lived agents, and investigates the
optimality properties of an equilibrium with or without sequentially complete markets. Various Pareto optimality concepts
are considered, including interim and ex ante optimality. We show that, at an equilibrium with a productive asset (land) and sequentially complete markets, the intervention
of a government may be justified, but only to improve risk sharing between generations. If markets are incomplete, constrained
interim optimality is investigated in two-period lived OLG economies. We extend the optimality properties of an equilibrium with
land and give conditions under which introducing a pay-as-you-go system at an equilibrium would not lead to any Pareto improvement.
Received: October 5, 1998; revised version: April 3, 2001 相似文献
65.
The present paper demonstrates the applicability of population based search optimization method, namely, Differential Evolution
(DE) to a case study of Mahi Bajaj Sagar Project (MBSP), India. Ten different strategies of DE are employed to assess the
ability of DE for solving higher dimensional problems as an alternative methodology for irrigation planning. The parameters
considered in DE are population size, crossover constant and weighting factor. Linear Programming (LP) is utilized as a comparative
approach to assess the ability of DE. Comparison of results of LP and the 10 DE strategies for the given parameters indicated
that both the results are comparable even for high dimensional problems. Extensive sensitivity analysis studies, performed
for 3,600 combinations of above parameters for the 10 DE strategies suggested that DE/rand-to-best/1/bin strategy is the best
strategy giving maximum benefits taking minimum CPU time. It is concluded that DE can be utilized for efficient planning of
any irrigation system with suitable modifications. 相似文献
66.
Lake-Level Change and Water Balance Analysis at Lake Qinghai,West China during Recent Decades 总被引:7,自引:0,他引:7
Xiao-Yan Li He-Ye Xu Yong-Liang Sun Deng-Shan Zhang Zhi-Peng Yang 《Water Resources Management》2007,21(9):1505-1516
Lake Qinghai, the largest saline lake with an area of 4,260 km2 (2000) and average depth of 21 m (1985) in West China, has experienced severe decline in water level in recent decades. This
study aimed to investigate water balance of the lake and identify the causes for the decline in lake level. There was a 3.35-m
decline in water level with an average decreasing rate of 8.0 cm year−1 between 1959 and 2000. The lake water balance showed that mean annual precipitation between 1959 and 2000 over the lake was
357 ± 10 mm, evaporation was 924 ± 10 mm, surface runoff water inflow was 348 ± 21 mm, groundwater inflow was 138 mm ± 9 and
the change in lake level was −80 ± 31 mm. The variation of lake level was highly positively correlated to surface runoff and
precipitation and negatively to evaporation, the correlation coefficients were 0.89, 0.81 and −0.66, respectively. Water consumption
by human activities accounts for 1% of the evaporation loss of the lake, implying that water consumption by human activities
has little effect on lake level decline. Most dramatic decline in lake level occurred in the warm and dry years, and moderate
decline in the cold and dry years, and relatively slight decline in the warm and wet years, therefore, the trend of cold/warm
and dry climate in recent decades may be the main reasons for the decline in lake level. 相似文献
67.
68.
Dieter Joachim Ziegenhagen 《保险科学杂志》2002,91(3):259-277
At present, our society and its social security system are not prepared to cope with the challenges resulting from the continuous increase of life expectancy. The traditional concept of disease has to be modified for serving the special needs of the elderly. The optimistic compression of disease theory is an intriguing model, but lacks prove by available data. The anti-aging boom diverts the focus from the social and financial burden that will be unevitably caused by long-term care in the future. If there will not be an — up to now unforeseeable — breakthrough in research, particularly dementia will have an enormous impact on social cost which is often underestimated. 相似文献
69.
Efficient Liability Rules: Complete Characterization 总被引:5,自引:0,他引:5
Received May, 18, 2000; revised version received March, 19, 2001 相似文献
70.
Identification of critical erosion prone areas in the small agricultural watershed using USLE,GIS and remote sensing 总被引:10,自引:1,他引:9
In the present study, Karso watershed of Hazaribagh, Jharkhand State, India was divided into 200 × 200 grid cells and average
annual sediment yields were estimated for each grid cell of the watershed to identify the critical erosion prone areas of
watershed for prioritization purpose. Average annual sediment yield data on grid basis was estimated using Universal Soil
Loss Equation (USLE). In general, a major limitation in the use of hydrological models has been their inability to handle
the large amounts of input data that describe the heterogeneity of the natural system. Remote sensing (RS) technology provides
the vital spatial and temporal information on some of these parameters. A recent and emerging technology represented by Geographic
Information System (GIS) was used as the tool to generate, manipulate and spatially organize disparate data for sediment yield
modeling. Thus, the Arc Info 7.2 GIS software and RS (ERDAS IMAGINE 8.4 image processing software) provided spatial input
data to the erosion model, while the USLE was used to predict the spatial distribution of the sediment yield on grid basis.
The deviation of estimated sediment yield from the observed values in the range of 1.37 to 13.85 percent indicates accurate
estimation of sediment yield from the watershed. 相似文献