"With stock market confidence already shattered, some floor traders at the New York Stock Exchange are taking drastic measures to ward off further bad luck this Friday the 13th.</br></br>They are wearing hats.</br></br>Today is ""Hat Day"" on the exchange, and word has gone out that members must cover their pates -- or be prepared to suffer the consequences.</br></br>According to Arthur Cashin, a floor broker for PaineWebber Inc., the logic couldn't be simpler: As everybody knows, it's bad luck to wear a hat indoors; but since today is Friday the 13th, the reverse should hold true. So wear a Stetson, fedora, Yankees cap or bowler. Then, stand back and watch the bull market roar.</br></br>Maybe that'll happen, maybe not. On the most recent previous Hat Day -- it came on Nov. 13, 1987 -- traders showed up sporting everything from football helmets to women's straw hats, the price tags still attached. And with the October crash fresh in their minds, a surprising number of them kept their hats on throughout the day, hoping for one good session in an otherwise unnerving season."