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1.
《Ecological Economics》2001,36(3):427-441
In recent years, different types of bio-economic models have been developed to support the analysis of the potential impact of agrarian policies on changes in land use, sustainable resource management and farmers' welfare. Most bio-economic models rely on series of discrete input–output coefficients for current and improved cropping and livestock activities, whereas mathematical programming procedures are usually applied to analyse optimum allocative choice. Adequate procedures for the smooth integration of biophysical information into economic decision models are, however, not readily available. This article provides a new and comprehensive framework for the incorporation of technical input–output coefficients derived from agroecological simulation approaches into bio-economic farm household models. Therefore, continuous production functions are estimated for the production side of the farm household model, making use of meta-modelling principles. It is shown that meta-modelling offers considerable scope for improving the specification and behaviour of bio-economic farm household models. This procedure is applied in a farm household model developed for the analysis of farmers’ response to agrarian policies in Southern Mali. Results are presented for the behaviour of a typical household, focusing attention on the trade-offs between farm income and soil nutrient balances under free market conditions and with constraints on labour, capital and animal traction markets. The stability and robustness of the model is analysed through a simulation of the impact of higher input costs for land use and fertiliser applications.  相似文献   

2.
This paper proposes a new approach to measure the impact of a sector's price shock on price indices. It works based on table adjustments to trace the effects of any initial price shock through an iteration process. It has the same accuracy and all the capabilities of the popular Standard Leontief Price (SLP) model. A distinct advantage of the new approach compared with the SLP model, however, is its ability to measure the impact of the initial price shock on all value-added components if and when it is required. This capability enables researchers to use interindustry price analysis to tackle problems of a more real-world nature. Other advantages of this approach are its simple computational implementation, especially relevant for larger size interindustry tables, the unified way to deal with all kind of different price issues, and the yielding of an adjusted interindustry table reflecting all endogenous price adjustments in response to the initial price shock.  相似文献   

3.
Using a bio-economic model of zebra mussels (Dreissena polymorpha), we examine the expected economic value of prevention, control and eradication alternatives for the freshwater mussel in Lake Okeechobee (Florida, USA). We include two emerging technologies for zebra mussel (ZM) control: (1) a natural pesticide called Zequanox, and (2) hot wash stations at boat ramps. We employ water management district data, user data collected via a phone survey, and mitigation expenditures from infested locations elsewhere to estimate the potential damage from the introduction of zebra mussels in Florida. Methods used include static cost transfer estimation, econometric cost estimation, and stochastic-dynamic simulation. We use our bio-economic model to compare costs and risks with and without the emerging technologies. We also consider the impact of technology adoption rates by anglers, management policy efficacy, and opportunity costs associated with ZM control. Results indicate that, without investment in prevention, there is a very high probability that Florida waterways will be infested with zebra mussels by year 2025, and expected environmental damages and management costs are high. Slow response due to poor detection methods or insufficient control efforts will lead to a moderate probability of a significant infestation. Rapid reaction and enhanced prevention efforts are expected to greatly reduce the probability of ZM infesting Lake Okeechobee by 2025, and to generate much higher expected net benefits.  相似文献   

4.
This paper sets out to assess the workability of the regulation currently in force in the European anchovy fishery of the VIII division. Particular attention is paid to the importance of the institutional regime in the allocation of natural resources. The study uses a bio-economic approach and takes into account the fact that, not only the European Union and the individual countries involved, but also some of the resource users or appropriators intervene in its management. In order to compare the effectiveness of the rules which, at the various levels, have been set up to restrict exploitation of the resource, the anchovy fishery is simulated in two extreme situations: open access and sole ownership. The results obtained by effective management will then be contrasted with those obtained from the maximum and zero profit objectives related with the two above-mentioned scenarios. Thus, if the real data come close to those derived from the sole ownership model it will have to be acknowledged that the rules at present in force are optimal. If, on the other hand, the situation more closely approach the results obtained from the open access model, we will endeavour in our conclusions to provide suggestions for economic policy measures that might improve the situation in the fishery.  相似文献   

5.
开矿导致地表植被破坏,并使植物群落结构发生改变。以零星矿井式开采的四川马边白家湾矿区为研究区域,通过群落调查,采用重要值和物种多样性指数,结合除趋势典范对应分析(DCCA)排序和多元回归进行数据分析,研究了开矿对植物多样性格局的影响。结果表明:(1)随着开矿干扰减弱,植物群落分为明显的四个群丛,依次由草本向灌木、乔木顺序演替;(2)开矿干扰与DCCA轴紧密相关,是影响植物多样性的重要环境因素,导致乔木层盖度变化且对多样性有直接影响;(3)群落间相似性与开矿干扰负相关,而物种替代速率与开矿干扰呈U型关系。  相似文献   

6.
The purpose of this paper is to estimate athletic performance profiles over time, to establish that diminishing returns is a characteristic of performance functions, to measure the rate of the marginal decline, and to measure the upper (lower) bound or limit of performance. The empirical results yield estimates of the limiting value of athletic performance and the frontier maximum (minimum) record. Since lower bounds in the running events have been shown to be sensitive to choice of the nonlinear model, logistic and an exponential model for the men's running and distance events are estimated as a cross-check on my differential equation model. The issue of the gender gap (whether women will ever catch men) in athletic performance is also explored.  相似文献   

7.
This paper estimates a structural macroeconomic model using data for Macedonia and Slovakia to characterize possible challenges Macedonia can face concerning macroeconomic stabilization during its transition process. A comparison of the estimated model parameters suggests that, in Slovakia, the output gap is less sensitive to real interest rate movements and prices experience greater inertia. The estimated monetary policy reaction functions show Macedonia and Slovakia as inflation targeters, with Macedonia as the more conservative one, despite its officially applied exchange rate targeting regime. The differences in the estimated parameters imply differing transmission mechanisms for Macedonia and Slovakia. Consequently, the variance of domestic variables in Slovakia is most influenced by monetary policy shocks, while there is no single dominating shock explaining the volatility of Macedonia's macroeconomic variables. The exchange rate shock, the monetary policy shock and the demand shock are jointly important in determining the volatility of Macedonia's variables. The model simulations indicate that Macedonia experiences lower output gap and inflation volatility than Slovakia. This comes, nevertheless, at the cost of higher interest rate and real exchange rate volatility in Macedonia, which could be an indication of more volatile financial markets with possible negative implications for financial stability.  相似文献   

8.
This paper investigates the impact of economic growth, and more specifically robust economic growth along with other macroeconomic determinants, on poverty levels using both the U.S. official measure of poverty and an estimated time series of Sen indices of poverty. The results reveal that the period of robust economic expansion that the U.S. economy experienced during the 1990s did not have a significant impact on poverty using either measure. In addition, we find that the impact of growth and other macro controls is dramatically different when a subset of the poverty population, namely non-white poverty, is investigated. The percentage of households headed by women is shown to be a significant factor in examining poverty for this subgroup.  相似文献   

9.
North-East Arctic cod is shared by Russia and Norway. Taking its multi-cohort structure into account, how would optimal management look like? How would non-cooperative exploitation limit the obtainable profits? To which extent could the strategic situation explain today’s over-harvesting? Simulation of a detailed bio-economic model reveals that the mesh size should be significantly increased, resulting not only in a doubling of economic gains, but also in a biologically healthier age-structure of the stock. The Nash equilibrium is close to the current regime. Even when effort is fixed to its optimal level, the non-cooperative choice of gear selectivity leads to a large dissipation of rents.  相似文献   

10.
We consider competing functional groups of tree species and develop a model of network response dynamics in order to measure the impacts of perturbations on the population distribution and diversity. The analysis of the equilibrium states relies on the connection between mean field game dynamics and replicator dynamics. We simulate our theoretical results from the data inventoried in French Guiana. Our results show that different types of disturbances modify the competitive interactions by affecting the evolutions of group densities. At the high regimes of disturbance, the canopy shade-intolerant species supplant the canopy shade-tolerant species. Tropical forest managers can thus take advantage of the competitive interactions between the functional groups to stimulate the abundance of marketable timber species. We also validate the hypothesis of maximum diversity at the intermediate disturbance levels.  相似文献   

11.
The commonly used conditional autoregressive range model with Weibull distribution (henceforth WCARR) suffers from serious inlier problem. We conjecture that this problem is due to a misspecified distribution to the disturbance, and propose a conditional autoregressive range model with gamma distribution (henceforth GCARR) to model the volatility of financial assets. In this paper, we first discuss the theoretical properties of the GCARR model and then compare its empirical performance with the WCARR. Empirical studies are performed on a broad set of stock indices in different countries over different time horizons. Consistent with the conjecture, we find that the GCARR model can reduce not only the inlier problem but also the outlier problem of the WCARR model. The results indicate that our GCARR model describes the dynamics of the range-based volatility better than the WCARR model and thus serves as a better benchmark.  相似文献   

12.
In this article, we use the macroeconometric model SLOPOL10 to calculate simulations of the development of the Slovenian economy until 2030. Starting from the present favourable prospects of the European economies, the forecast is very optimistic but it can nevertheless be improved by optimal fiscal policies as calculated using the OPTCON2 algorithm. If a negative shock to world trade of a size comparable to the Great Recession occurs, it will entail a decline in GDP and a slow recovery. In this case, optimal fiscal policies should not act in an expansionary way as the effectiveness of fiscal policy with respect to output and employment is rather limited in a small open economy like Slovenia. Instead, the goal of budget consolidation will call for a more restrictive fiscal policy, at least if the shock is temporary.  相似文献   

13.
In this paper we present a model from which discretionary consumption dynamics can be analyzed as global properties emerging from the endogenous transformation of a society inhabited by boundedly rational interactive consumers. By considering local and global interactions among consumers, we show that behavioral diversity plays a central role in the evolution of consumption patterns. The analysis of the model reveals the existence of a regime characterized by the persistence of different social standards, and a time evolution of the social distribution of behavioral patterns towards a heteroclinic cycle. In some cases the evolution seems to be chaotic, generating unpredictable, erratic dynamics of the aggregate social indices (average or social propensity for discretionary consumption).   相似文献   

14.
《China Economic Journal》2013,6(3):361-381
A small-scale New-Keynesian dynamic stochastic general equilibrium model is estimated by maximum likelihood method using quarterly data of China. Model specifications and parameter equalities between various competing model variants are addressed by formal statistical hypothesis tests, while implications for business cycle fluctuations are evaluated via a variance decomposition experiment, second-moments matching, and some out-of-sample forecast exercises. It is highlighted that both forward and backward components are important for the dynamics of output, inflation and real balances. The monetary authority will take a sufficient aggressive stance, with a significant lagged response, to the current inflation pressure, while leaving less attention to changes in aggregate output. Variance decomposition reveals that large percentages of variations in real and nominal variables are explained by the highly volatile preference shock and potential output shock, respectively. When nominal and real frictions as well as additional shocks are included, our estimated model overall can successfully reproduce the stylized facts of business cycles in the actual data of China and even frequently outperform those forecasts from an unconstrained VAR.  相似文献   

15.
This paper studies financial friction arising from oligopolistic bank competition and its impacts on a small open economy's business cycles by applying imperfect competition and endogenous firm entry theory. Using Australian data, the estimated model implies a countercyclical mark up in lending rate that varies inversely with number of banks. Such bank sector has a distinct shock propagation mechanism that often amplifies business cycles, depending on the type of shock. Balance sheet effects appear different compared to competitive banks, due to strategic bank behaviour. Unlike previous estimated small open economy general equilibrium studies, the model can capture substantial international transmissions.  相似文献   

16.
This paper examines the behavior of four types of markup measures and its implications for the new Keynesian Phillips curve (NKPC). The four types of measures are a procyclical measure, a weakly procyclical measure, an acyclical measure and a countercyclical measure. Motivated by the fact that the U.S. markup has shifted up dramatically since the early 2000s, the paper also presents both empirical dynamics and a new Keynesian model featuring nonstationary markups. After inspecting empirical dynamics of key macroeconomic variables and the performance of the model, it points out that weakly procyclical or acyclical markups are more consistent with the purely forward-looking NKPC. Moreover, a major shortcoming of standard new Keynesian models is their inability to trace the actual behavior of the markup in response to a demand shock.  相似文献   

17.
We analyze the feedback mechanisms between economic downturns and financial stress for several euro area countries. Our study employs newly constructed financial condition indices that incorporate banking variables extensively. We apply a non-linear Logistic Vector Smooth Transition Autoregressive (LVSTAR) model for investigating instabilities in the link between the financial sector and economic activity. The LVSTAR model allows for non-linear dynamics and regime changes between low and high stress regimes. It can also replicate the regime-specific amplification effects shown by our theoretical model. The amplification effects, however, change over time. Specifically after the Lehman collapse, we observe the presence of strong non-linearities and amplification mechanisms for some euro area countries. Thus, these strong amplification effects appear to be related to rare but large events, and to a low-frequency financial cycle. Prior to the financial crisis outbreak we find corridor stability even if the financial sector shock takes place in a high stress regime. More important seems to be the shock propagation over time in the economy. Only with the occurrence of rare but large events we find strong endogenous feedback loops and a loss of stability as described by the high stress regime of our theoretical model. The economy leaves the corridor of stability and is prone to adverse feedback loops.  相似文献   

18.
With a thin economic component, most bio-economic models of fisheries failto assess the effects of the regulation systems on firms. In order to analysethe short term consequences of different management schemes, a simulationmodel is applied to the French driftnet albacore fleet: licence allocation withdriftnet regulation, individual quotas, and individual transferable quotaswithout any input control. Vessel technology is estimated by using the datacollected, and groups of vessels are distinguished according to criteria ofperformance. We present the adjustment within firms and between groupsunder different scenarios (limited entry with and without driftnetregulation, individual quotas and individual transferable quotas allocation),and we compare their results in terms of quasi-rent value and otherindicators such as hake harvests or dolphin by-catches.  相似文献   

19.
Existing literature on the role of intellectual property rights (IPR) protection has painted an ambiguous picture about the size of the effects of stronger IPR on the choice of the multinational firm’s mode of entry into foreign market. Some empirical studies suggest that improving IPR in recipient countries will have higher effect on licensing, while others found larger effect on foreign direct investment (FDI). The available indices of protection only measure country-wide characteristics and do not pick inter-industry variation, while the data show significant differences in losses of US multinationals by industry. In this paper, we introduce and empirically estimate a new dimension to multinational firm’s decision to enter a foreign market—a parameter that reflects the length of positive profits that the firm can earn in various industries. We dub the estimated parameter a perceived time of rent extraction. The introduction of the time parameter allows us to differentiate the effects of stronger IPR on the entry modes in different industries and reconcile the ambiguity results in the literature. Particularly, strengthening IPR has higher impact on FDI in industries with shorter rent extraction time, while licensing is affected more than FDI in industries with longer rent extraction time.  相似文献   

20.
A simple N-country specific-factor-type model with imperfectly mobile labour is developed. It is shown that the effects of country-specific productivity shocks hitting a small country have fundamentally asymmetric effects: A positive shock will be accommodated by a moderate wage increase and sizeable in-migration, whereas a negative shock will be accommodated by a significant decrease in wages and moderate out-migration. It is argued that the results of the model are consistent with the recent Irish experience. The welfare effects of small economic fluctuations are also discussed.  相似文献   

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