投机心理会产生投机-泡沫效应，投资者为了追求超额回报导致股票市场泡沫概

Speculative psychology will produce a speculative-bubble effect. In order to pursue excess returns, investors will increase the probability of the stock market bubble, causing the price of new stocks to rise on the first day of listing, resulting in IPO underpricing. There may be no underestimation of stock prices, but excessive pursuit of the secondary market will cause it to deviate from the real price. Since investors are attracted by the excessive returns in the issuance of new shares, they will subscribe for new shares to obtain higher returns, so there will be many applicants for new shares. Investors who cannot successfully subscribe will switch to the secondary market. When the stock is listed on the secondary market, those investors who did not subscribe at the issue price will speculatively buy the stock in the secondary market, resulting in stock issuance. The rate of return on that day was much higher than the average rate of return, and prices were pushed up, resulting in IPO underpricing.

Speculation psychology will produce speculative-bubble effect, investors in order to pursue excess returns lead to the probability of stock market bubble increase, causing the price of new shares to rise on the first day of listing, resulting in the phenomenon of IPO price suppression. Stock prices may not be undervalued, but excessive pursuit in the secondary market can cause them to deviate from real prices. As investors are attracted by the excess returns of the new issue process, they will subscribe for new shares for higher returns, so there will be a lot of buyers of new shares. Unable to bid for a successful investor will switch to the secondary market, when the stock is listed in the secondary market, those who do not subscribe at the issue price will speculatively buy the stock in the secondary market, resulting in the stock on the day of the issue yield is much higher than the average yield, the price is pushed up, resulting in an IPO price.

Speculative psychology will generate speculative bubble effect. Investors will increase the probability of bubbles in the stock market in pursuit of excess returns, causing the price rise on the first day of IPO, resulting in the phenomenon of IPO underpricing. The stock price may not be undervalued, but the excessive pursuit of the secondary market will lead to its departure from the real price. Because investors are attracted by the excess return in the IPO process, they will subscribe for new shares to obtain higher return, so there will be many new subscribers. Investors who can't purchase successfully will switch to the secondary market. When the stock is listed in the secondary market, those investors who don't subscribe at the issue price will buy the stock speculatively in the secondary market, resulting in the yield on the day of the stock issue is far higher than the average yield, and the price is pushed up, resulting in IPO underpricing.<br>