The longer you appease on Facebook , the nearer the chance of you witness a " we did n’t have seatbelt / prophylactic features / basic concerns for our survival ask whenIwas a kid and we still pull round " office arrest to 100 percent .
If you have n’t bump them , retrieve of the person who tells you " my gran smoke every day of her life and she made it to 95 " or " I used to pound 35 cans of Budweiser before every commute and not once did I die " from Uncle Billy . These are all exercise of " survivor bias " , which rifle like this : these activities look less grave than they are because you are one of the survivors . There ’s a ground you do n’t get wind from masses with similar story , such as " I used to lumber 35 rump of Budweiser before drive and died instantly , daytime one " from Uncle Billy ( God rest his soulfulness ) , and it ’s because Uncle Billy is idle .
allow ’s move aside from the uncheerful examples , and take a flavor at a couple that graze up on the cyberspace from time to time : The helmet and the plane . warfare are a great place to line up subsister , hence why these account both take place during a warfare .
The WWI Helmet
This one , though likely apocryphal , travel like this : In WWI , generals start to become alarmed when hospital started to see a large number of headland injuries to soldier in hospitals . have the inflow , they thought that the problem might be that the freshly introduced helmet – the Brodie helmet , specifically – might be causing head injuries . In fact , the understanding why they were seeing so many head injuries is that the helmet were let far more soldiers to survive .
The Planes
During World War II , the Americans desire to reduce the casualty rate of their tune squadron . Many planes come back riddled with bullet hole in three main field : the fuselage , the outer wing , and the tail . They come up up with the result to reward the hell out of the areas that had been replete with enemy fire . Which seems logical enough .
However , the reason why this is such a dandy example of subsister bias is that theonlydata they had to go on was from the survivor . Before they could start to reinforce the region , Abraham Wald , a Magyar - Judaic mathematical statistician took a look at the data and realized the fault in their logical thinking .
In essence , the bullet holes in the fuselage , outer wings , and tails on the planes that survived showed this : if planes could be shot full of smoke in those three orbit and make it back , that meant that being shot there was n’t very dangerous to the planes . If you assume ( and you have to make assumptions as you arenot control all the evidence , as it ’s lying somewhere in a state of war zona ) that bullet gob are distributed jolly evenly over planes when you look at all the planes that go out to fight , that means that the ones thatdidn’tmake it back likely had smoke holes in other area . His answer was to calculate for the survivor bias , and suggest that they should reward all the arena thatdidn’thave smoke maw , in lodge to increase survival .
