Effect Changes in Investor Attitude.
研究了二战后美国上市公司投资者态度的变化，从长期持有转向投机和程序化交易，对理解现代股市行为有参考价值。
Abstract This article focuses on the change in the attitude of various investors in publicly owned companies. Since World War II, business entities have increased in size and complexity, both in the U.S. and around the world. Larger accounting firms with more specialization and a much expanded scope of practice have entered an era of greater competition. The most significant and far-reaching change is the development of new attitudes by the investors in the thousands of publicly owned companies. Until the 1950s, much of the stock in American companies was held by families of the founders and other long-term investors. Only a few million shares were traded each day. Since that time, much additional stock has been sold to the public and many more companies have become publicly owned in the truest sense of that term. In recent years, stocks have been involved in the futures markets through options and stock-index futures. This development, along with the use of computers, has resulted not only in more speculation but also in new activities such as program trading, portfolio insurance, and index arbitrage. Many large institutional investors no longer trade individual stocks but rather entire portfolios worth billions of dollars.