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31.
Election forecasting has become a fixture of election campaigns in a number of democracies. Structural modeling, the major approach to forecasting election results, relies on ‘fundamental’ economic and political variables to predict the incumbent’s vote share usually a few months in advance. Some political scientists contend that adding vote intention polls to these models—i.e., synthesizing ‘fundamental’ variables and polling information—can lead to important accuracy gains. In this paper, we look at the efficiency of different model specifications in predicting the Canadian federal elections from 1953 to 2015. We find that vote intention polls only allow modest accuracy gains late in the campaign. With this backdrop in mind, we then use different model specifications to make ex ante forecasts of the 2019 federal election. Our findings have a number of important implications for the forecasting discipline in Canada as they address the benefits of combining polls and ‘fundamental’ variables to predict election results; the efficiency of varying lag structures; and the issue of translating votes into seats.  相似文献   
32.
We compare the performance of a wide set of regression techniques and machine-learning algorithms for predicting recovery rates on non-performing loans, using a private database from a European debt collection agency. We find that rule-based algorithms such as Cubist, boosted trees, and random forests perform significantly better than other approaches. In addition to loan contract specificities, predictors that refer to the bank recovery process — prior to the portfolio’s sale to a debt collector — are also shown to enhance forecasting performance. These variables, derived from the time series of contacts to defaulted clients and client reimbursements to the bank, help all algorithms better identify debtors with different repayment ability and/or commitment, and in general those with different recovery potential.  相似文献   
33.
We analyze the impact of product diversification on performance. This topic has been discussed in the literature, and there is no consensus so far as to the significance or the direction of the impact. Performance is measured using Tobin's q for a sample of 103 large, non-financial Spanish firms (1992–1995). Diversification is measured by means of a categorical variable, as suggested by Varadarajan. The principal results indicate that the firms with intermediate levels of product diversification have the highest performance, while the firms with low and high levels of diversification show significantly lower performance, which performance is not significantly different between them.  相似文献   
34.
This study presents theoretical arguments and evidence that attempt to show the contribution of economic mechanisms typical of a business for resolving problems of environmental protection. Firstly, a brief synopsis is given of the classic solutions that environmental economics proposes for correcting environmental externalities. Next, the benefit of expanding these two mechanisms is discussed so that they include those intermediate mechanisms for which it is not possible to clearly establish if they are developed within the domain of the market or the business. The study's focus resides in the fact that the explicit expansion of the range of solutions proposed from a macroeconomic point of view establishes a connecting point between environmental economics and business economics, an area in which academic attention to environmental matters has been significantly less. The present work forms part of research project SEC2002-00835, financed by MCYT-FEDER.  相似文献   
35.
Recent research in natural sciences shows that the dynamics in boreal forests are much more complex than what many models traditionally used in forestry economics reflect. This essay analyzes some challenges of accounting for such complexity. It shows that the optimal harvesting strategy for forest owners is history dependent and for some states of the forest, more than one strategy may be optimal.This paper confirms earlier literature on shallow lakes and coral reefs and shows that this kind of phenomena seem much more common than previously thought. They are valid for a wide range of ecosystems that cover large surfaces and they do not depend on the choice of some specific function to model the non-linearity. There are also indications that theses results could be obtained even for resources with concave growth if at least one species with non-linear growth affects their dynamics.  相似文献   
36.
Summary. All agents have the same ordinal ranking over all objects, receiving no object (opting out) may be preferable to some objects, agents differ on which objects are worse than opting out, and the latter information is private. The Probabilistic Serial assignment, improves upon (in the Pareto sense) the Random Priority assignment, that randomly orders the agents and offers them successively the most valuable remaining object. We characterize Probabilistic Serial by efficiency in an ordinal sense, and envy-freeness. We characterize it also by ordinal efficiency, strategyproofness and equal treatment of equals. Received: October 5, 1999; revised version: December 20, 2000  相似文献   
37.
38.
In the mid-nineties FIFA decided to increase from two to three the number of points assigned to the winning team of a soccer match played under traditional round-robin national leagues. Since a game of soccer can be regarded as a contest, FIFA's measure provides an interesting case-study for analysing how a change in the system of rewards (from a zero to a non-zero sum rule) may affect the contestants' equilibrium behaviour. In this paper we try to assess, both theoretically and empirically, whether FIFA's new point rule has changed soccer towards a more offensive game, in which teams adopt more risky strategies. In particular, we evaluate the “na?ve hypothesis” according to which the measure would induce every team to play always more offensively, and we explore the extent to which the change in teams' behaviour may be affected by quality differentials between teams. Our most important hypothesis is that when the asymmetry between opposing teams is large enough, an increase in the reward for victory induces the weaker team to play more defensively, rather than the opposite. By looking at a subset of matches held in the Portuguese first division league, which approximate the conditions of our model, we find support for this hypothesis. First version received: July 1999/Final version received: May 2001  相似文献   
39.
Rennison (Comparing alternative output gap estimations: a Monte Carlo approach, 2003) has provided simulation-based evidence showing that the joint use of extended multivariate filters and structural vector autoregression models is optimal for estimating potential output. We use this approach to estimate the two components of potential GDP: the full-employment labour input and trend labour productivity. This decomposition is useful for identifying sources of fluctuations in potential output. It reveals, for example, that the vigorous growth rate of U.S. potential GDP recorded during the second half of the 1990s is attributable to a fall in the structural rate of unemployment and a marked upswing in trend productivity growth.  相似文献   
40.
The slow and endogenous twist of economic macro-structure makes up an important evolutionary feature of capitalist economies, and may be at the root of structural crisis. In this line, a Goodwinian growth model with increasing returns and profit-sharing that tries to picture a simple scenario of the seventies crisis is considered. It is shown that the exhaustion of the Kaldor-Verdoorn “productivity law” can entail, in a nonlinear framework, a “catastrophic” bifurcation from a “high” to a “low” growth path. Slow/fast dynamical systems then allow one to formalize a multiple time-scales dynamics where the growth path is shaped by the structural framework in which it takes place, but has also a long -un feedback. Structural change and crisis appear as long term and endogenous outcomes.  相似文献   
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