Analysis of group behavior bias in financial markets using artificial market

Abstract

In the past few decades, researchers have realized that human psychology can affect traders in decision-marking process and finally affect the financial market based on behavior finance theory and cognitive psychology. Group behavior bias is one of them. Group. Some studies have been done on group behavior bias from behavior finance viewpoint to tell the differences of group behavior bias. However they only qualitatively analyzed macro phenomenon without quantitatively measure the detail micro thinking process in individuals. In this paper, we proposed and validated three types of group behavior bias models including majority following, winner following and hub following models based on different nationalities. We also compared these models and figured out that the majority following bias is the easiest to form in the market, however the market impact is the least. On the other hand, hub following bias is the hardest to emerge but the market impact is the most. Besides, we introduced short selling regulation as well as multi rate regulation and find both of them can lead heavier market impact in the market with group behavior biases.