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101.
In the current paper, we present an integrated genetic programming (GP) environment called java GP modelling. The java GP modelling environment is an implementation of the steady-state GP algorithm. This algorithm evolves tree-based structures that represent models of inputs and outputs. The motivation of this paper is to compare the GP algorithm with neural network (NN) architectures when applied to the task of forecasting and trading the ASE 20 Greek Index (using autoregressive terms as inputs). This is done by benchmarking the forecasting performance of the GP algorithm and six different autoregressive moving average model (ARMA) NN combination designs representing a Hybrid, Mixed Higher Order Neural Network (HONN), a Hybrid, Mixed Recurrent Neural Network (RNN), a Hybrid, Mixed classic Multilayer Perceptron with some traditional techniques, either statistical such as a an ARMA or technical such as a moving average convergence/divergence model, and a naïve trading strategy. More specifically, the trading performance of all models is investigated in a forecast and trading simulation on ASE 20 time-series closing prices over the period 2001–2008, using the last one and a half years for out-of-sample testing. We use the ASE 20 daily series as many financial institutions are ready to trade at this level, and it is therefore possible to leave orders with a bank for business to be transacted on that basis. As it turns out, the GP model does remarkably well and outperforms all other models in a simple trading simulation exercise. This is also the case when more sophisticated trading strategies using confirmation filters and leverage are applied, as the GP model still produces better results and outperforms all other NN and traditional statistical models in terms of annualized return.  相似文献   
102.
We explore whether the recent laboratory findings that suggest the origin of endowment matters in simple bargaining games are actually due to contextual shifts of relative effort and deservingness. Results support previous findings of endowment origin yielding more self-interested behavior.  相似文献   
103.
We provide new results for two-stage games in which firms make capacity investments when demand is uncertain, then, when demand is realized, compete in prices. We consider games with demand rationing schemes ranging from efficient to proportional rationing. In all cases, there is a subgame perfect equilibrium outcome coinciding with the outcome of the Cournot game with demand uncertainty if and only if (i) the fluctuation in absolute market size is small relative to the cost of capacity, or (ii) uncertainty is such that with high probability the market demand is very large and with the remaining probability the market demand is extremely small. Otherwise, equilibria involve mixed strategies. Further, we show under efficient rationing that condition (i) is sufficient for the unique equilibrium outcome to be an equilibrium outcome of the Cournot game with demand uncertainty.  相似文献   
104.
Previous studies have proposed that a compensatory model predicts the level of foreign direct investment (FDI) in a country; FDI levels are a result of ‘trade‐offs’ between the positive effect of market attractiveness and the negative influence of corruption. In contrast, we hypothesize and find that the compensatory relationship only holds for market‐seeking investment; for resource‐seeking FDI the model appears to be noncompensatory. Greater market attractiveness mitigates the negative impact of corruption on market‐seeking investment, but the ability of market attractiveness to mitigate the negative impact of corruption on resource‐seeking FDI quickly disappears as corruption levels increase. Implications and future research directions are discussed. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
105.
Abstract .  This paper provides a detailed empirical analysis of Canadian city housing prices. We examine the long-run relationship between city house prices in Canada from 1985 to 2005 as well as idiosyncratic relations between city prices and city-specific variables. The results suggest that city house prices are only weakly correlated in the long run and that there is a disconnect between house prices and interest rates. City-specific variables such as union wage levels and the issuance of building permits tend to be positively related to existing city house prices. Surprisingly, there is mixed evidence with respect to standard measures of economic activity such as per capita GDP and interest rates.  相似文献   
106.
This paper utilizes quantile-regression techniques in order to estimate the effects of demographics and maternal behavior during pregnancy at various quantiles of the birthweight distribution. Due to the high costs and long-term effects (both medical and economic) associated with low-birthweight babies, there is a great deal of interest in quantifying these effects, particularly at the lower end of the birthweight distribution. Using large samples of 1992 and 1996 births in the United States, the quantile-regression estimates indicate that several factors (including race, education, and prenatal care) have a significantly higher impact at lower quantiles and lower impact at higher quantiles. These effects at lower quantiles are underestimated by least-squares regression estimates. The inequality in birthweights implied by these results is quite significant, and there is little indication that the inequality has changed much in recent years.  相似文献   
107.
This paper compares estimates of value derived from conventional discounted cash flow and price earnings valuation methods to the market price. For a sample of 45 firms newly listed on the New Zealand Stock Exchange our results suggest that the best discounted cash flow method and the best price earnings comparable have similar accuracy. The median absolute pricing error is around 20% and the models explain around 70% of the cross-sectional variation in market price scaled by book value. The results serve to corroborate the findings of Kaplan and Ruback (1995).  相似文献   
108.
Using principal component analyses, this paper constructs two internationalization indices for the renminbi (RMB) and 32 other major currencies. We find that the RMB's currency internationalization degree index (CIDI) is still low, and far behind the 4 most important international currencies. In 2009, it was ranked 18th among all important international currencies. However, in terms of the currency internationalization prospect index (CIPI), the RMB has remained the world's fifth highest since 2006. Although it is still far behind the US dollar and the euro, surpassing the ranking of the yen and the pound is possible in the near future. The dramatic difference in the ranking between the CIDI and the CIPI is a result of China's tight capital account control, the usage continuity of international currency due to network externalities, and the narrow foreign exchange and imperfect financial markets. Hence, to a large degree, the RMB's potential as an international currency depends on China's capital account liberalization.  相似文献   
109.
In this paper, we develop a paleoeconomic model of the co-evolution of economic specialization and encephalization—the common physiological measure of intelligence as reflected by brain mass relative to total body mass. Our economic analysis links ecological and social intelligence theories of increased encephalization in early hominins through a model in which both economic and ecological feedbacks jointly determined the evolutionary incentives. We focus on degrees of specialization affected by coordination costs with and without market exchange. Our results suggest encephalization would be a process characterized by diminishing returns to behavioral advances. In terms of the long-running debate in economics over whether specialization increases or decreases intelligence, our results suggest from an evolutionary perspective the answer depends on economic/social institutions and how these influence ecological interactions.  相似文献   
110.
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