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When U.S. air force discovered the flaw of averages (2016)

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Re: When U.S. air force discovered the flaw of averages (2016)

#91

Post by smabie »

dragonwriter wrote: post #88
Worker32850 wrote: post #34

Earlier quoted context omitted.

Human dimensions are closer to a normal distribution. (Not quite normal, but let's pretend.) In that distribution then 46% of subjects should be in the middle 30% of 3 dimensions. [0] [0] With 4000 subjects they presumably have all sizes within ~3.5 stddevs represented. The middle ~1.2 stddevs should hold ~77% of the population. 0.77^3 = ~46%

> Human dimensions are closer to a normal distribution Human height is (it's the textbook example of a real, intuitive_that is, using the normal linear scale—physical measure that is a good fit for a normal distribution) plenty of other human dimensions are not.

Human height should be a negative binomial distribution, since human height can't be negative.

Re: When U.S. air force discovered the flaw of averages (2016)

#92

Post by jbay »

JoeAltmaier wrote: post #5

Been noted here on HN: the average web form excludes lots of people. Lots of folks cant fill in: First/middle/last name; unique username/password; social security number; street address; bank account. And not just folks in Micronesia or whatever. Heck my business partner hasn't got a deliverable street address - no mailbox at his house. He has a PO box. Is a nightmare getting Amazon deliveries that aren't lost, or le…

There's so many times that an ostensibly international website has rejected me because I don't have a US-formatted numerical zip code. Even when they have a country field.

Re: When U.S. air force discovered the flaw of averages (2016)

#93

Post by kristianp »

Talanes wrote: post #82
Retric wrote: post #28

Earlier quoted context omitted.

It’s two different effects. First being within a range is not the same as being at the center of the range. Someone 4% above average height should have ~50% of their dimensions larger than that. Similarly someone at 4% below average should have around 50% of their dimensions below that. At best someone in the exact middle of the range only has so much buffer to work with. Second the correlation is less significant th…

Every time I get my height measured by a new doctor, they feel the need to tell me that my legs are short for my height.

I don't recall ever having my height measured. Is that a U.S. doctor thing?

Re: When U.S. air force discovered the flaw of averages (2016)

#94

Post by joe-collins »

kristianp wrote: post #93
Talanes wrote: post #82

Earlier quoted context omitted.

Every time I get my height measured by a new doctor, they feel the need to tell me that my legs are short for my height.

I don't recall ever having my height measured. Is that a U.S. doctor thing?

Visits often start with a basic vitals check, but as an adult they've been content to simply ask my height, while measuring my weight.

Re: When U.S. air force discovered the flaw of averages (2016)

#95

Post by BeetleB »

noname120 wrote: post #31
MyHypatia wrote: post #26

Consider this set of statistics: 90% of elementary school teachers are female [1]. 90% of veterans are male [2]. Unsurprising. But, there are 2 million female veterans in the US, and only 1.7 million female elementary school teachers. That means if you talk to a random American female, it is more likely that she is a veteran than an elementary school teacher. I think a lot of disagreements on Hacker News and elsewher…

This is called Simpson's paradox[1]. [1] https://en.wikipedia.org/wiki/Simpson%27s_paradox

It's not an example of Simpson's Paradox. It's an example of the base rate fallacy.

https://en.wikipedia.org/wiki/Base_rate_fallacy

Re: When U.S. air force discovered the flaw of averages (2016)

#96

Post by BeetleB »

stcredzero wrote: post #21

I remember when this idea came around Hacker News the last time. I mentioned this over lunch, and one of my (highly respected and deservedly considered intelligent) younger coworkers called BS on it. His object was: "Why would a government build an expensive, high tech piece of equipment, then not ensure it could fit the operator?" He just couldn't imagine it. Between 2020 and WWII, there is a huge difference in avai…

> Why would a government build an expensive, high tech piece of equipment, then not ensure it could fit the operator?

Why would they send a $250M probe to Mars, and not ensure a consistent set of units is used?

I mean, putting the above two examples aside, one could list plenty of much bigger screwups by the government. Why is this person assuming a competent government?

I wish I knew the name for this fallacy, but it is essentially a restatement of "I can't think why X would behave this way, so it must be because Y." Or as I tend to call it: "Out of ignorance, comes certainty". I mean, you just admitted you didn't know! How are you drawing conclusions?

I blame Arthur Conan Doyle: https://www.goodreads.com/quotes/7471034-once-you-eliminate-...

Re: When U.S. air force discovered the flaw of averages (2016)

#98

Post by GarvielLoken »

BeetleB wrote: post #96
stcredzero wrote: post #21

I remember when this idea came around Hacker News the last time. I mentioned this over lunch, and one of my (highly respected and deservedly considered intelligent) younger coworkers called BS on it. His object was: "Why would a government build an expensive, high tech piece of equipment, then not ensure it could fit the operator?" He just couldn't imagine it. Between 2020 and WWII, there is a huge difference in avai…

> Why would a government build an expensive, high tech piece of equipment, then not ensure it could fit the operator? Why would they send a $250M probe to Mars, and not ensure a consistent set of units is used? I mean, putting the above two examples aside, one could list plenty of much bigger screwups by the government. Why is this person assuming a competent government? I wish I knew the name for this fallacy, but i…

Hanlon's razor. "Never attribute to malice that which is adequately explained by stupidity"

Re: When U.S. air force discovered the flaw of averages (2016)

#99

Post by redis_mlc »

Symmetry wrote: post #49

Huh, the conventional story is that the UN forces won the air war in Korea because of better plane ergonomics despite Migs having better theoretical performance. But this report didn't come out until the war was mostly over. The conventional story emphasizes things like bubble canopies but still.

> the UN forces won the air war in Korea because of better plane ergonomics

Well, the MiG-15 could outclimb our jets, but we got one and let Chuck Yeager test it.

After that, more equal.

Also, better visibility, comfort and I believe g-suits.

Re: When U.S. air force discovered the flaw of averages (2016)

#100

Post by noir_lord »

philwelch wrote: post #76
noir_lord wrote: post #59

Earlier quoted context omitted.

Not to mention desperation moves like the british STEN sub-machine gun which was basically what you get if you say "I need 800,000 of these and they just have to meet these criteria, eject everything else ". https://www.youtube.com/watch?v=8-PmLxkOmaM

The Sten was a beautiful accomplishment. Being cheap, simple, optimized for quick mass production, and just good enough to get the job done is a perfectly legitimate set of requirements. It’s like the IKEA LACK.

I never said it wasn't, My comment was on the requirements leading to the most stripped down possible design that still functioned.
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