School of Economics and Management, Beihang University, Beijing, China.
Beijing Advanced Innovation Center for Big Data and Brain Computing, Beihang University, Beijing, China.
PLoS One. 2018 Jun 18;13(6):e0197935. doi: 10.1371/journal.pone.0197935. eCollection 2018.
This paper presents results of an artificial stock market and tries to make it more consistent with the statistical features of real stock data. Based on the SFI-ASM, a novel model is proposed to make agents more close to the real world. Agents are divided into four kinds in terms of different learning speeds, strategy-sizes, utility functions, and level of intelligence; and a crucial parameter has been found to ensure system stability. So, some parameters are appended to make the model which contains zero-intelligent and less-intelligent agents run steadily. Moreover, considering real stock markets change violently due to the financial crisis; the real stock markets are divided into two segments, before the financial crisis and after it. The optimal modified model before the financial crisis fails to replicate the statistical features of the real market after the financial crisis. Then, the optimal model after the financial crisis is shown. The experiments indicate that the optimal model after the financial crisis is able to replicate several of real market phenomena, including the first-order autocorrelation, kurtosis, standard deviation of yield series and first-order autocorrelation of yield square. We point out that there is a structural change in stock markets after the financial crisis, which can benefit people forecast the financial crisis.
本文介绍了一个人工股票市场的结果,并试图使其更符合真实股票数据的统计特征。基于 SFI-ASM,提出了一种新的模型,使代理人更接近真实世界。根据不同的学习速度、策略大小、效用函数和智能水平,将代理人分为四种类型,并找到了一个关键参数来确保系统稳定性。因此,添加了一些参数,以使包含零智能和低智能代理的模型能够稳定运行。此外,考虑到金融危机导致实际股票市场波动剧烈,将实际股票市场分为金融危机前和金融危机后两个阶段。金融危机前的最优修正模型未能复制金融危机后真实市场的统计特征。然后,展示了金融危机后的最优模型。实验表明,金融危机后的最优模型能够复制实际市场的几个现象,包括一阶自相关、峰度、收益率序列的标准差和收益率平方的一阶自相关。我们指出,金融危机后股票市场存在结构性变化,可以帮助人们预测金融危机。