Cui Lijie, Lin Chuandong
School of Labor Economics, Capital University of Economics and Business, Beijing 100070, China.
Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-Sen University, Zhuhai 519082, China.
Entropy (Basel). 2020 Jul 17;22(7):778. doi: 10.3390/e22070778.
A simple and effective lattice-gas-automaton (LGA) economic model is proposed for the income distribution. It consists of four stages: random propagation, economic transaction, income tax, and charity. Two types of discrete models are introduced: two-dimensional four-neighbor model (D2N4) and D2N8. For the former, an agent either remains motionless or travels to one of its four neighboring empty sites randomly. For the latter, the agent may travel to one of its nearest four sites or the four diagonal sites. Afterwards, an economic transaction takes place randomly when two agents are located in the nearest (plus the diagonal) neighboring sites for the D2N4 (D2N8). During the exchange, the Matthew effect could be taken into account in the way that the rich own a higher probability of earning money than the poor. Moreover, two kinds of income tax models are incorporated. One is the detailed taxable income brackets and rates, and the other is a simplified tax model based on a fitting power function. Meanwhile, charity is considered with the assumption that a richer agent donates a part of his income to charity with a certain probability. Finally, the LGA economic model is validated by using two kinds of benchmarks. One is the income distributions of individual agents and two-earner families in a free market. The other is the shares of total income in the USA and UK, respectively. Besides, impacts of the Matthew effect, income tax and charity upon the redistribution of income are investigated. It is confirmed that the model has the potential to offer valuable references for formulating financial laws and regulations.
本文提出了一种简单有效的用于收入分配的格子气自动机（LGA）经济模型。该模型包括四个阶段：随机传播、经济交易、所得税和慈善。引入了两种离散模型：二维四邻模型（D2N4）和D2N8。对于前者，一个主体要么保持不动，要么随机移动到其四个相邻的空位置之一。对于后者，主体可以移动到其最近的四个位置之一或四个对角位置。然后，当两个主体位于D2N4（D2N8）的最近（加上对角）相邻位置时，随机发生经济交易。在交易过程中，可以考虑马太效应，即富人赚钱的概率高于穷人。此外，纳入了两种所得税模型。一种是详细的应税所得税率表，另一种是基于拟合幂函数的简化税收模型。同时，考虑慈善时假设较富有的主体以一定概率将其一部分收入捐赠给慈善事业。最后，通过两种基准对LGA经济模型进行了验证。一种是自由市场中个体主体和双职工家庭的收入分配。另一种是美国和英国各自的总收入份额。此外，研究了马太效应、所得税和慈善对收入再分配的影响。证实该模型有潜力为制定金融法律法规提供有价值的参考。
