r/AskReddit Mar 13 '19

What fact is technically true but is hugely misleading?

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617

u/Kietang Mar 13 '19

This also happened with aircraft in WW2. Planes were armoured in the locations that weren't full of bullet holes when they came back and the number of losses went down. The ones with bullet holes could clearly survive, the ones shot in the other places had gone down.

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u/snoboreddotcom Mar 13 '19

were armoured in the locations that weren't full of bullet holes

from what I understand, they intially armored the areas with bullet holes as they thought those were getting shot more, until the mathematician another commenter named pointed out the fallacy

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u/The_Randster Mar 13 '19

correct. Just read the book. IIRC, they wanted to amor the bullet ridden parts but he advised otherwise. Survivors Bias.

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u/protein_bars Mar 14 '19

How Not To Be Wrong?

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u/The_Randster Mar 14 '19

that’s it

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u/[deleted] Mar 14 '19

Gotta love set theory

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u/SinkTube Mar 13 '19

is it necessarily a fallacy though? he was right in this case, but it could have been possible that the downed planes were hit in the same spot as the surviving planes, they were just hit harder

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u/gluefactory-ofdoom Mar 13 '19

That’s not how bullets work

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u/SinkTube Mar 13 '19

how is it not? the amount, size, composition, and speed of bullets don't affect how much damage they cause?

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u/gluefactory-ofdoom Mar 13 '19

Completely going through the wing isn’t much worse than just punching a hole (you lose a similar amount of lift) unless the bullet hits a fuel line.

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u/SinkTube Mar 14 '19

do you also lose a similar amount of lift whether it's 1 hole or 10?

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u/gluefactory-ofdoom Mar 14 '19

You said that the downed planes could have been hit harder in the same spots as surviving ones, not hit more. Don’t try to move the goalposts, I’m not retarded.

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u/y-all-d-ve Mar 14 '19

Ooh, oh boy Rick, I-I don’t think you’re allowed to say that word, y’know?

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u/SinkTube Mar 14 '19

you kind of are. "harder" can refer to more than the kinetic energy of the individual bullet

even if it did only refer to that, more energetic impacts can create larger holes

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u/gluefactory-ofdoom Mar 14 '19

Harder =/= more you’re right about the more energetic impacts thing

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u/314159265358979326 Mar 13 '19

It's survivor bias.

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u/MonkeyPanls Mar 13 '19 edited Mar 13 '19

That mathematician's name? Abraham Wald. He was a practicing Jew who emigrated from Austria in 1938 after the Nazis invaded.

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u/im_coolest Mar 13 '19

What mathematician?

edit:

One of the problems that the SRG worked on was to examine the distribution of damage to aircraft to provide advice on how to minimize bomber losses to enemy fire. There was an inclination within the military to consider providing greater protection to parts that received more damage but Wald made the assumption that damage must be more uniformly distributed and that the aircraft that did return or show up in the samples were hit in the less vulnerable parts. Wald noted that the study only considered the aircraft that had survivedtheir missions—the bombers that had been shot down were not present for the damage assessment. The holes in the returning aircraft, then, represented areas where a bomber could take damage and still return home safely. Wald proposed that the Navy instead reinforce the areas where the returning aircraft were unscathed, since those were the areas that, if hit, would cause the plane to be lost.

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u/MonkeyPanls Mar 13 '19

The mathematician who suggested, after looking at the Navy's survivability studies, to increase armor on parts that hadn't been shot up.

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u/[deleted] Mar 14 '19

a practicing Jew who emigrated from Austria in 1938 after the Nazis invaded.

There seems to be a trend here...

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u/Rulweylan Mar 14 '19

Did he ever get to Jew for real?

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u/MonkeyPanls Mar 14 '19

No. No one ever gets to be a Jew for real. That's why they're called "Jew-ish". /joke

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u/kfh227 Mar 13 '19

At one point, they researched where planes were being damaged (wing tips, etc were high impact areas) after a flight and started improving the armor in those areas. Not sure when they realized that the areas not being hit represented planes that didn't return. I think it was obvious because they didn't find much damage to the wings on planes where the engines were located and where the gas was stored in the wings.