Deviations from novice luck to survivors

Deviations from novice luck to survivors

ESRI Lu Meng, China

Gamblers believe that "beginners are always lucky. Almost all gamblers think that "Although luck will gradually deteriorate later, it is always lucky to start gambling ".

 

Aside from the professional casinos, it is not worth the money that the banker has put on a long term. Even in the stock market, there are often such cases. Luck is especially good when new people enter the market.

 

Is it true that a newbie is lucky? Before discussing this issue, let's take a look at the professional term "Survivor vorship bias" in statistics. In addition, it is translated as "Survivor deviation" or "Survivor deviation ", it is a common logical fallacy ("fallacy" rather than "deviation"), which means that only the results produced by certain filtering can be seen, but the screening process is not realized, therefore, key information filtered out is ignored. There are many aliases for this item, such as "Silent data" and "dead will not talk.

 

He first came from a story during World War II.

 

During the Second World War, the US-British coalition troops carried out a strategic bombing of Germany. As the German Army's air defense firepower was unprecedented, the Allied planes suffered heavy losses. The Air Force and pilots both strongly demand enhanced protection capabilities. The simplest method is to install bulletproof armor on the plane.

 

However, during World War II, the power of the aircraft was limited. If all the armor was installed, the whole body would be overweight, resulting in difficult takeoff and slow operations. Therefore, only bulletproof armor can be partially installed.

 

The military invited Professor Abraham Wald, a well-known statistician at Columbia University, to analyze coalition planes hit by German air defense.

 

Professor Ward issued a statistical table to aircraft maintenance personnel to show the area of the plane. After a period of time, the two tables are summarized, with the largest number of bullet points on the wing, while the engine and the pilot cockpit are basically blank, with almost no bullet.

 

After seeing the statistical report, the military director immediately decided to install the armor on the wing. But Professor ward immediately put an end to the military's decision.

 

Professor Ward believes that this statistical report is the result of our maintenance personnel counting from the plane that has been flown back. That is to say, although the wing has a lot of shells, it can still return smoothly after the bullet, it just shows that the wing is not the most important part to be protected. The engine and cockpit do not have a record of bounce because, as long as the two places are bounce, the plane crashed almost. Therefore, the engine and cockpit are the most protected parts.

 

The plane that was hit by the engine and cockpit was shot down, so it did not enter the study sample. They all become "dead people who don't talk ".

 

This is the deviation of survivors in statistics. If the premise of the data you collect is wrong, then the beautiful statistical formula or method, and more data cannot make the subsequent inferences correct.

In this case, the "Newbie lucky" we have seen above is a survivor's deviation.

 

First of all, we all know that gamblers are at a disadvantage in casinos, or in stock markets, and casinos or bankers are at a dominant position. If you bet first, if you win (lucky), most of the new gamblers will think that they have suffered the fate and will continue to gamble.

 

What about the lost ones? They may be disappointed and stop gambling. Therefore, when the samples of gamblers are counted, the losers who leave the gambling table will not appear in the samples.

 

The loser may watch birds, graffiti, become a pirate, or engage in other recreational activities. Those who continue to gamble will remember that they were lucky new players. Those who give up gambling are not defined as gamblers. Therefore, in statistics, gamblers are lucky new players.

 

Professor Liu shunren of Taiwan University gave an example of "Survivor deviation" in his book "victory", which is the most vivid and clear.

 

He gave an example of money fraud (which has evolved to the E-Mail version ).

 

On June 23, January 2, you received an anonymous letter indicating that the market will rise this month. As a result, the market actually rose, but you did not agree with it, as we all know, there is a lunar January effect (over the past January S, the stock price has risen and fallen ).

 

In February 1, you received another letter saying that the market would fall. This time, I spoke to the letter again.

 

I received another letter in May March 1, in the same situation. In this way, you are very interested in the foresight of the anonymous, and then the other party invites you to invest in an overseas fund.

 

So you took out all your savings and invested it. Two months later, the money was like a steamed stuffed bun and you couldn't go back. You burst into tears on the shoulder of your neighbor. He told you that he also received two mysterious emails, but it stopped when he sent the second one. He said that the predictions for the first round are correct, but those for the second round are incorrect.

 

What is this?

 

The trick of scammers is that they find 10 thousand people in the phone book, send a bullish email to half of them, and send a bearish email to the other half.

 

A month later, five thousand people will receive the correct predictions, and then target these five thousand people.

 

After another month, the remaining two thousand five hundred people received the correct predictions, so that until the remaining five hundred people on the list, of which two hundred were cheated, the scammers only needed to spend thousands of dollars in postage, you can earn millions of dollars.

 

This is "Survivor's deviation". As long as the information is not circulated, "the dead will not speak." other people do not know how accurate this scammers are.

Deviations from novice luck to survivors