炒股的正确思考模式：先要不亏钱，然后才赚钱

编者前言：

如果你喜欢看Deal or No Deal这个电视节目，你一定会设身处地问自己：如果换了我来做这个游戏，我是继续碰运气呢，还是接受已经到手的钱。正如文中所讲的，大多数人选择的是碰运气，因为大家只关心能赚多少钱，而不考虑失误和亏损的可能，也就是只想回报、不问风险。这和买彩票的心态是一样的，虽然中头奖和被雷劈的概率差不多，每次投入的钱等于100%亏损，但人们还是经不住诱惑，原因就是只专注于“有可能”赚到的钱，而忘记了更大的可能性是亏钱。在股票投资中，我们面临着同样的问题。你为什么喜欢买低价的股票？为什么想知道目标价？为什么决定炒外汇？是不是因为满眼都是哗啦啦的钞票，希望更多更快地赚到钱？

可是你真的赚到了吗？要不要换一个思考模式，先不要考虑赚钱，想一想怎么避免失误，怎么保证不亏钱。电影《Wall Street》中的Gordon Gekko说过一句至理名言：I don't throw darts at a board. I bet on sure things. Read Sun-Tzu, The Art of War. Every battle is won before it's ever fought. 设计一个交易系统，列出所有可能失败的因素，选择成功概率最高的机会下手，争取每一次都有十足的把握。当你把所有亏钱的可能性都排除，剩下的自然就是赚钱了……

Deal or Bad Deal?
Be smart when taking risks with your own money

By Chuck Jaffe, MarketWatch.com, March 15, 2006

A friend of mine warned me that I would hate the hit NBC game show "Deal or No Deal," so I didn't bother watching until last week, when it was being aired while I was captive on two cross-country flights.

He was right; I hate the show.

The problem is that now that I have seen it, I can't stop watching because it's a live-action financial train wreck where people showcase the kind of thinking that short-circuits investment decisions. Contestants routinely make horrible, nonsensical, illogical choices that, when not made in the context of a game show, can create real financial hardships.

To see why that is, you have to understand the game and the underpinnings of financial decisions.

"Deal or No Deal," hosted by comedian Howie Mandel, involves a contestant who is given the choice of 26 cases, each held by a model and filled with a card representing an amount of money between one cent and $1 million. The amounts are placed randomly in the cases.

The contestant picks one case to be their own, then proceeds to call out numbers, so that the models can open other cases and reveal their contents.

As those cases are opened, the potential reward awaiting the contestant starts to take shape. Knock out the low-dollar values, and the odds of getting a big reward increase.

Periodically, however, the game's "banker" calls host Mandel. He is making an offer to the contestant of a certain amount of money, effectively the "expected value" of all of the remaining amounts left on the board. Contestants can accept the banker's deal, or open more cases, knowing that the very next case could wipe out their hope for capturing the big jackpot, and that the banker will respond by lowering the next offer accordingly.

Take the case of a recent participant, who was down to four possibilities, two under $250, then $50,000 and $500,000. He was offered nearly $140,000 to walk away, and he had a 75 percent chance of leaving with an amount much lower. Never mind that the offer was several times the guy's annual salary, the guy was playing with fire.

Of course, it's a game. Talk to anyone who has seen the show and they will say how they might take chances on television that wouldn't happen in real life.

But if they have a life insurance policy and are offered a life-settlement or viatical settlement -- basically allowing them to get a slug of money now to walk away from the eventual benefits of their policy -- they're facing a "Deal or No Deal" kind of situation.

Even in choosing stocks, where an investor might be deciding between a safe, steady return expected from an established dividend-paying stock and the potential rocket-like returns of the red-hot issue-du-jour, the decision is too often based on the wrong inputs.

"People don't have a good intuitive grasp of probabilities, and thus they will be swayed by things that shouldn't be swayed by," says Terence Odean, a professor at the University of California-Berkeley who examines behavioral finance. "It applies to investors just like it does people on the game show. They see the potential of a big number, and they take too much risk trying to get it, and wind up making poor choices as a result."

Anyone watching the game can see many different types of poor behaviors at work. Players will knock out a few low numbers in a row and will say -- or be told by their supporters -- that they are on a "hot streak," when in truth each pick is random and they have no way of divining the right numbers.

They overestimate their abilities, or see trends where none exist given the random nature of the game.

They have a tough time figuring the probabilities, even though the smart money -- the "banker" in the case of the game -- is doing just that.

"People cannot factor in uncertainty, so they edit it out, discount it and ignore it," says Donald McGregor of MacGregor-Bates Inc., a Eugene, Ore. firm that does research and consulting in judgment and decision-making. "So they focus on the outcomes and remove the uncertainty and deal only with what is concrete and in front of them."

"When that happens, they tend to focus on the big payoff, not the potential loss. It's why people buy lottery tickets, despite horrendous odds and don't think about what they are losing while the spend hundreds or thousands of dollars. It's why they pass up a good thing to take one more shot at $500,000 on the show, and it's why they look at initial public offerings and remember the Microsofts and Googles without remembering the many other companies that totally failed at the same time."

While most of us will never be contestants on a game show, we are constantly facing gambles and decisions. Finding the ones where the numbers work just a bit in your favor tends to be better than always playing for the big score.

It's why you should insure your house, but not your DVD player; the coverage on the appliance is expensive for the potential payout, while the house is such a big thing that it demands the coverage because it would be so difficult to replace.

"People have to understand that there is a point where their decisions go from being risky -- which is fine -- to being reckless," says Meir Statman, a professor of finance specializing in investor decision-making at Santa Clara University. "The point often depends on someone's circumstances. A person with a lot of money can take more chances; to them, a few thousand dollars difference is probably not a life-changing event.

"What people must realize is that good outcomes aren't going to happen just because they're hoping for the best. Factoring in the downside risk, coming up with a probability for success and deciding just which risks you can stomach is the best way to get through most financial decisions without having too much regret."

编者：三维预测网站