[b]Hieronymous' Study of Futures Traders[/b] [quote]Traders who had made more than 10 trades over the course of the year or had losses or gains in excess of $500 were tallied.[/quote] Why is this grouped as a day trader? A day trader is going to have thousands of trades a year. Oh, this was 1969 before computers. Bad study and not relevant. [b]The Johnson Report on Day Traders[/b] Study too small. Not relevant. [b]Odean's study of stock traders[/b] [quote]According to Odean, not very much. Commissions were an important part of the reason why active traders had the worst performance, but the main bogeyman was the bid/ask spread. In fact Odean believes that traders as a group are now doing even worse than they did in the old discount brokerage days because turnover has increased even more. Odean offers the following example: The average trade in his sample was roughly $13,000 in size. Trading through a discount broker, an investor might have paid $60 or so in commissions "round-trip," or $30 for the buy and $30 for the sale. But by Odean's estimate, the typical investor also lost a full 1% to the bid-ask spread -- or $130 on this typical $13,000 purchase.[/quote] Outdated. I pay $7.95 a trade - and that includes both ends of the trade. Bid/ask spread of 1%? LOL. Bid/ask spread is pennies now. Spread on Apple right now is $0.11 - on a $395 stock. A 1% spread would be $3.95. Obviously, we are not in a world of 1% bid/ask spreads anymore on stocks that are routinely traded. Garbage study. In short, the studies referenced suck and are outdated.