Abstract
The paper consists of two parts. In the first part of this research, we evaluate the level of informed trading of TWSE (Taiwan Stock Exchange) listed stocks by using dynamic intraday measure of the probability of informed trading (DPIN measure) published in Chang, Chang and Wang (2014). In addition, with the unique dataset of traders’ types from TWSE, we distinguish the DPIN with four groups, namely, individual, funds, foreign investor and other corporation, to discuss the level of private information in different types of traders, in stock of different industries, under different levels of trading volumes, or under different market regulations (the shrink of time spread between each deal). In the second part of the paper, we choose 10 stocks from TAI 50 to discuss the feasibility of using DPIN as criteria to practice high-frequency trading. We identify and follow the informed traders by DPIN and the unexpected return. Ignoring trading costs, our results show that most stocks have positive accumulative return. That said, our primitive trading strategies are unprofitable if trading costs are taken into account. We then add three more criteria and extend the holding period of each transaction to decrease the frequency of trading, to improve the ability to predict the changing direction of stock price, and to well-capture the local price trends. This modified trading strategies generate substantially higher profits relative to the buy-and-hold market portfolio, even when transaction costs are taken in account.