随着行为金融学的不断成熟与发展，从投资者的行为出发研究股票市场泡沫的成

With the continuous maturity and development of behavioral finance, studying the causes and formation process of stock market bubbles from the behavior of investors has become a hot spot for scholars at home and abroad. Investors in the market are always affected by various factors such as their own psychological deviation and external objective environment when making decisions. The concept of investor sentiment is proposed, and they believe that investors’ behavioral decisions are not completely rational and are easily affected by external factors. The influence of factors such as group effect, self-confidence, heterogeneous beliefs, etc., causes investment subjects to have herd behavior and form group bias. This group deviation phenomenon will cause various anomalies in the market and even cause substantial fluctuations in stock prices. At the same time, under the guidance of leveraged funds, the changes in investor sentiment will be amplified to a certain extent, which in turn will accelerate the rate of stock market bubbles. Therefore, starting with investor sentiment and combining the utility of leveraged funds to study the changes of investment subjects can accurately describe the effect on the stock market, and then understand the internal mechanism of the stock market speculative bubble.

With the maturity and development of behavioral finance, it has become a hot topic for scholars at home and abroad to study the causes and formation of stock market bubbles from the behavior of investors. Investors in the market will always be influenced by their own psychological deviation, external objective environment and other factors, put forward the concept of investor sentiment, think that investors' behavior decision-making is not completely rational and thus easy to be affected by the external group effect, their own excessive self-confidence, heterogeneity beliefs and other factors, so that the investment subject exists from the public behavior, forming a group bias. This kind of mass deviation causes the market to produce various visions and even causes large fluctuations in stock prices. At the same time, under the guidance of leveraged funds, it will make the change of investor sentiment amplify to a certain extent, and then make the stock market bubble production rate accelerate. Therefore, starting with investor sentiment, combined with the utility of leveraged funds to study the changes of investment subjects can accurately depict the role of the stock market, and then understand the internal mechanism of speculative bubbles in the stock market.

With the continuous maturity and development of behavioral finance, the study of the causes and formation process of stock market bubbles has become a hot topic of scholars both at home and abroad. Investors in the market are always affected by their own psychological deviation, external objective environment and other factors when making decisions. This paper puts forward the concept of investor sentiment, and holds that investors' behavior decision-making is not completely rational, which is easily affected by the external group effect, their own overconfidence, heterogeneous beliefs and other factors, so that investors have herd behavior, The formation of group bias. This kind of group deviation phenomenon will make the market produce all kinds of anomalies, and even cause the stock price to fluctuate greatly. At the same time, under the guidance of leveraged funds, investors' mood will be enlarged to a certain extent, which will accelerate the stock market bubble. Therefore, from the perspective of investor sentiment and the effectiveness of leverage, studying the change of investors can accurately depict the role of stock market, and then understand the intrinsic mechanism of stock market speculative bubbles.