41 ms·

How the US Air Force Ditched the Average and Saved Lives

tomohawk 4y ago
This also comes into play with the current discussion of EVs. People will say, "you don't need that 500 miles of range." Or, "just plug the EV in at night - you don't have to wait at the charger." That probably works well for average use cases, but not for the outliers. The great thing about ICE vehicles is you generally don't have to worry about non-average use cases. To reach parity, EVs will need to be chargable in 5 minutes from empty to achieve 500 miles of range, at 5 degrees F, with 5 year old batteries. If you live in California, that may seem like an extreme use case, but it's pretty normal around here.
- gonzo41 4y ago
  If the EV market could agree on a battery size and configuration, then maybe doing a full swap of a battery could be done like an f1 Pitstop. Similar to those electric scooters in Asia, Just imagine if you rolled over a pitstop and had the battery quicky taken out from below the car and then a new battery placed back in. That sort of system could change the economics of building an ev as you could move to a model where users don't really own the battery they rent it for a while until they need a swap. Or electric cargo bicycles. Because every bike on the road is one less massive car.
  - cguess 4y ago
    Battery degradation would limit expectations. "Oh shit, I got one of those old batteries that will only get me 150 miles when I was hoping for 200 to get to my mother-in-law's for Thanksgiving" isn't going to work.
    - lillecarl 4y ago
      Could be solved by measuring how much charge it takes and bills you for that + some min charge for the change service would be the price, a bit more complex but I reckon the swap service could be made simple enough that it's low cost.
    - ljosifov 4y ago
      Then you are going to drive 150 miles and spend extra 3 mins to change the battery again - no? Not a big deal, and certainly not a deal breaker. Nah - the pit-stop type battery replacement is the obvious solution to most EV charging problems, but we humans can not execute it. It requires level of coordination and cooperation between companies that we are not easily capable of right now.
      - bluGill 4y ago
        Battery replacement works only if you make compromises. EVs are currently designed to put batteries where they fit, a standard battery means much less batteries and thus much less range. Second cars come in different sizes, a swappable battery needs to fit in the smallest car, leaving larger cars with a much to small battery. Sure it can work, but overall I have to call it a bad compromise.
  - PaulRobinson 4y ago
    You’re making the mistake of average use cases. Your first idea requires new, expensive infrastructure that will need maintenance due to mechanical parts. Given charging points are regularly broken at the moment, I don’t have high hopes. But even if we overcame that: it’s impractical in almost every major city in the World, because you’d have to drastically alter existing spaces, such as filling stations. This might work in your context, and many others. It might even work for the “average” use case. But for 75% of the developed World (where the EV market is the fastest growing), I’m not convinced. And the electric cargo bike argument - or bikes in general - work great for the “average” journey, but not many people actually take that journey. My most frequent drive is 200+ miles in normally wet or cold weather. My next most frequent is 15+ miles in baking hot Summer sunshine in a heavily congested city where I need aircon. Neither would be pleasant on a bike - electric or not. And I think that’s the point of this discussion: engineering for averages is a terrible idea, and most EVs don’t work for most journey profiles for most of the World’s drivers today, compared to ICE
  - spoonjim 4y ago
    I don’t think this will ever happen. You will need to inventory $30,000 parts to sell them for $30,005 (if $5 is the cost of the charge). And the cars will have to have tons of design compromises.
  - giaour 4y ago
    There was an Israeli startup that tried this out ~10 years ago: https://jalopnik.com/battery-swapping-israeli-startup-better-place-is-dead-510139169 https://jalopnik.com/battery-swapping-israeli-startup-better... One problem was that they had chosen one model of car to simplify battery inventory, but the car was not a good fit for their initial markets.
  - nradov 4y ago
    Nio is doing battery swapping successfully with their EVs in China. https://www.nio.com/blog/current-state-ev-battery-swapping https://www.nio.com/blog/current-state-ev-battery-swapping
  - Hellbanevil 4y ago
- CogitoCogito 4y ago
  EVs don't need to entirely displace ICEs. Many zealots think so, but it isn't even necessary from an environmental perspective. But I think the main complication comes to ownership. Are you going to own an EV and an ICE? Or are you doing to own and EV and rent an ICE when needed? Or the other way around? And even if you rent it can become complicated. Last weekend I rented a car and it needed to be an EV since I booked it late and that's all that was late. I personally would rather not have dealt with the extra complexity of charging it compared to just putting gas in the tank. But really I thin the issue is that if we move to EVs it kind of forces some sort of vehicle specialization where it previously didn't feel as necessary. That opens a big can of worms when it comes to changes in lifestyle for many people.
  - bluGill 4y ago
    I'm surprised you can rent an EV. Few hotels have a place to charge them, so there goes the idea of plugging them in overnight, which is the main advantage of EVs
    - zoover2020 4y ago
      In the US maybe. Lot's of countries which offer charge capabilities for EVs everywhere, even at hotels (The Netherlands, Norway etc.).
      - hef19898 4y ago
        I've even seen fast chargers at petrol stations in Tunsia this year, all the way down in the South not to far from the Lybian border.
    - chrisseaton 4y ago
      You can go to a normal super-charger while you have breakfast or whatever.
  - AnIdiotOnTheNet 4y ago
    You know what else is going to open a big can of worms when it comes to changes in lifestyle for many people? Climate change.
- ajconway 4y ago
  Alternatively, the charging infrastructure needs to evolve. Even considering the currently available technology, imagine having 150kW chargers in place of every gas station that we have right now. Install ~20 chargers in the most busy locations, and the average time spent at the station will no be much higher than getting gas.
- formerly_proven 4y ago
  Frankly I do not want to share streets with people who drive 800 km, refuel and drive even more after that in one go.
  - qikInNdOutReply 4y ago
    [flagged]
  - jmillikin 4y ago
    There's a joke that goes something like "To an American 200 years is a long time, to a European 200km is a long distance". Driving from San Diego to Sacramento is about 800km; in good weather and light traffic you could cover that in 7 or 8 hours. Get up early, drive that first leg, stop for lunch, then keep going (e.g. towards Portland or Seattle). Of course, an American would usually stop for gas before hitting empty because we're used to the idea of "No food or fuel next 2 hours".
    - jfk13 4y ago
      A couple of decades ago, when I was young(er) and (more) foolish, I several times did the drive between Columbia, SC and Dallas, TX in a single day. It was just a touch over a thousand miles. Idiocy.
      - k__ 4y ago
        My grandfather drove us to holiday from Germany to Spain every year. Took 2-3 days. He slept a few hours in the car at night.
      - h2odragon 4y ago
        I once did a whirlwind trip from TN to NM, UT, CO, and back to TN. 5,000+ miles in 5 days. Average speed over 40MPH with some sleep and some meetings included. Idiocy, indeed.
    - ghaff 4y ago
      7 or 8 hours is a pretty long day driving for one person. But people do switch off and, even in New England where distances tend to be shorter, a 5 hour drive up to somewhere like Maine is hardly exceptional.
- Andys 4y ago
  I thought this until I looked at the histogram of private car trip lengths. The vast majority of trips are very short. Its unlikely they're all being done on the same day.
  - tomohawk 4y ago
    Next time you have to bug out because there's a hurricane coming, and it's after your commute, so you haven't had time to charge the car, are you going to be regretting your choice? It's 95F out, humid, and your car AC is going full bore as you creep along in traffic to get out of the area. Yes, that is not an average situation, but there's a lot of peace of mind not having to think about it at all. By the time I get down to 250 miles in my ICE, I can fill up in 5 minutes, but still have a very comfortable margin for anything that may happen. And, worst case, if I run out of gas (never happened in my lifetime)? I can get a gallon of fuel and drive away. How does that work with an EV?
    - k__ 4y ago
      Sounds like a very US specific problem to me.
      - seansmccullough 4y ago
        A reasonable US-specific problem. EV limitations like this are are why millions of people aren't currently interested in buying EVs. Compared to ICE, and EV car is more expensive, and essentially has the "road trip" feature removed.
- namdnay 4y ago
  I think the main mistake as concerns EVS (and many other environmental questions) is the belief that tomorrow will have exactly the same comforts as yesterday. If having to wait 45mn every 400km is the biggest price you’re paying for the carbon transition, you’re very lucky
cm2187 4y ago
The other massive misuse of average I keep hearing is people referring to the life expectancy at the XVIII century. Yeah it was 40 something but not because it was very rare for people to reach 60, but because the average is dragged down by the high infant mortality rate. Once you reached 20, your life expectancy was a bit lower than today, but it was common for people to reach 60. And in general people are really bad at thinking in term of distributions. If you discuss averages or percentiles, people identify to that metric like if it applied to every individual of that distribution. That makes the debate on D&I particularly unproductive.
- mdp2021 4y ago
  It is helpful to say that at first quintile they died at around 10 years of age and at last quintile they died at around 70 (with a median at 33). The average may remain 40, but you get a better idea of the distribution.
- elephant_burger 4y ago
  To your point, the global “average” life expectancy since the 1700s to today visualized https://ourworldindata.org/grapher/life-expectancy?tab=chart&time=1770..2019&country=Africa+Asia+Europe+OWID_WRL+Americas+Oceania https://ourworldindata.org/grapher/life-expectancy?tab=chart...
  - bigDinosaur 4y ago
    How to mislead with data 101!
    - jwlit 4y ago
      Indeed, though see the article linked at the bottom of that one, which goes into more of the nuance and has distribution curves etc: https://ourworldindata.org/life-expectancy-how-is-it-calculated-and-how-should-it-be-interpreted https://ourworldindata.org/life-expectancy-how-is-it-calcula...
- jarenmf 4y ago
kqr 4y ago
The other common misuse of averages I keep hearing confusing "the average X" with "the X of the average Y". (Known formally as Jensen's inequality.) So for example, the average time to review a code change is not the same as the time it takes to review a code change of average size. The average user experience of a website is not given by the user experience of the average response time. And so on. People tend to compute the average of an easier variable and then forget that the derived value of interest is often nonlinear in the easier variable.
- hackernewds 4y ago
  very interesting. what is the suggested correct way then?
  - kqr 4y ago
    Draw a random sample of easy variables from the underlying distribution, compute the variable of interest on all of those, then average.
- blt 4y ago
  Nit: Jensen's inequality only applies when the "derived value of interest" is a convex function of the "easier variable".
Foomf 4y ago
I absolutely love this article, and I like to re-read it every once in a while. It talks about the same thing: https://www.thestar.com/news/insight/2016/01/16/when-us-air-force-discovered-the-flaw-of-averages.html https://www.thestar.com/news/insight/2016/01/16/when-us-air-...
- elephant_burger 4y ago
  Thank you for sharing. This is the first chapter from Todd Rose's excellent book The End of Average. In the book, he also touches on the fascinating topic of context. For example there is no such thing as a person's average level of aggression - IF I am around my parents I tend to get aggressive, but IF I am around friends and strangers I am calm. https://www.penguin.com.au/books/the-end-of-average-9780141980034 https://www.penguin.com.au/books/the-end-of-average-97801419...
  - giardini 4y ago
    FWIW the face of the statue of the "the typical woman 'Norma'" at https://www.thestar.com/news/insight/2016/01/16/when-us-air-force-discovered-the-flaw-of-averages.html https://www.thestar.com/news/insight/2016/01/16/when-us-air-... resembles Dana Scully of The X-Files. I also enjoyed Todd Rose's book, which examines the history of (mis-)interpretations and (mis-)uses of the "average": The End of Average https://www.amazon.com/End-Average-Unlocking-Potential-Embracing/dp/0062358375 https://www.amazon.com/End-Average-Unlocking-Potential-Embra...
    - leoc 4y ago
      Even Rose's article (I haven't read his book yet so I can't really say about that) tiptoes around what was going on here. It wasn't just a naive application of statistics. Rose gets through the Norma story without mentioning eugenics once, but the whole episode is so obviously part of America's pre-WWII eugenics swoon. Beyond specific beliefs about politics, race or genetics, but linked to them, there was a whole Zeitgeist, the collectivist spirit of the age that gave us Busby Berkeley musical numbers https://www.youtube.com/watch?v=ysvQ5MaUbd8 https://www.youtube.com/watch?v=ysvQ5MaUbd8 and the IBM company songbook https://www.networkworld.com/article/2333702/a-history-of-singing-the-big-blues.html https://www.networkworld.com/article/2333702/a-history-of-si... . This was a time when it was acceptable, indeed it was progressive, to be violently hostile to difference or defectiveness: see for example War Against the Weak https://waragainsttheweak.com/ https://waragainsttheweak.com/ and, maybe most especially, The Black Stork https://global.oup.com/academic/product/the-black-stork-9780195077315 https://global.oup.com/academic/product/the-black-stork-9780... . And of course it's no coincidence that the pioneers of statistics tended to be particular fans of eugenics themselves. (I am not an expert on anything.)
_the_inflator 4y ago
Also have a look at Anscombe's Quartet to get literally an overview, what averages can mean: https://en.wikipedia.org/wiki/Anscombe%27s_quartet https://en.wikipedia.org/wiki/Anscombe%27s_quartet
jimhefferon 4y ago
Another interesting, and very readable, article on the subject is What does the mean really mean? https://arxiv.org/abs/2003.01973 https://arxiv.org/abs/2003.01973
robg 4y ago
Probability and statistics should have already replaced algebra and calculus in modern education. People are just really bad at understanding variance and the impacts on what we think we know.
- BurningFrog 4y ago
  My gut feeling is that the education sector is extremely conservative and keeps teaching whatever is has always teached. This is one argument for homeschooling, I guess.
  - solardev 4y ago
    Anecdata (I wanted to be a teacher earlier on until I actually met a few and heard their stories): Teachers are generally pretty progressive (both in the political and innovation senses), but the legislation (like Common Core), state & district educational standards, and school boards move more slowly. And in the US, the primary schools are largely funded and overseen by local parents (municipal and state), so the school priorities and cultures partially reflect local priorities. There's often debate between what individual teachers want to teach (a product of their individual preferences and backgrounds and values) vs what the administration forces them to teach (as a reflection of the political and business realities of their particular school). There's often a personality difference between the two classes too (educators vs admin types), with the former often being (at a stereotype) starry-eyed idealists and the latter being grounded management types with an eye on the numbers of finance and politics; on top of that, there is also often a labor vs mgmt (not quite "owners") divide, with individual teachers being pretty much powerless to teachers' unions being really strong in some districts. Long story short, teachers can't unilaterally change the curricula they teach. The power struggles affect everything from math (new math, math wars, whether to test it, etc.) to social studies (CRT, Native studies, bilingualism, religious studies) to science (evolution, climate) to business needs (cursive vs typing, algorithms or letterheads), etc. Far from being a settled matter, our educational system is heavily political and its lack of progress is probably reflective of our divisiveness as a country, where two broad sides keep playing tug-of-war and veering towards the extremes, making tiny gains and losses back and forth. The kids end up caught in the crossfire. The US, for all the money we pour into education, ends up rather poorly educating its children vs other developed nations: https://en.wikipedia.org/wiki/Programme_for_International_Student_Assessment#PISA_2018_ranking_summary https://en.wikipedia.org/wiki/Programme_for_International_St...
AdrianB1 4y ago
The article is a short, low quality version of the previous several ones that were explaining in detail the history, the changes, the results. It does not belong here.
- leoc 4y ago
  Yes, compared to Todd Rose's own article telling the story https://www.thestar.com/news/insight/2016/01/16/when-us-air-force-discovered-the-flaw-of-averages.html https://www.thestar.com/news/insight/2016/01/16/when-us-air-... this feels like a bland summary. Mind you, even Rose's version waters things down quite a bit: https://news.ycombinator.com/item?id=31961179 https://news.ycombinator.com/item?id=31961179 .
qalmakka 4y ago
There was this Roman poet, Trilussa, which created a good description of why averages are bad, which is known in Italy as "Trilussa's Chicken" Roughly translated, it goes as follows: "Following the current statistics, it turns out you're expected to be able to eat one chicken per year, and, if you can't afford it, it goes into the average anyway, because there's someone else out there eating two".
- HideousKojima 4y ago
  The average human has one breast and one testicle (give or take a fraction).
- Phiwise_ 4y ago
  Rome had a conception of statistics? That's very interesting. I'd always been told that it was a relatively new science coming from french aristocracy gambling or something.
  - mdp2021 4y ago
    Carlo Salustri, artistically signing with the anagram Trilussa, died in 1950.
  - GavinMcG 4y ago
    I too read "Roman" to refer to empire. Maybe because of the Latin-sounding single name, or maybe because I'm used to identifying people by their nationality rather than their city.
  - qalmakka 4y ago
    Sorry, it's modern Roman, not ancient. Trilussa wrote in Romanesco, which is a Central Italian dialect (Tuscan and central Italian form a somewhat of a linguistical continuum, while southern Italian and northern languages are not mutually intelligible).
- huachimingo 4y ago
  It is the same as Nicanor Parra's: There are two pieces of bread. You eat two. I eat none. Average consumption: one bread per person
martincmartin 4y ago
Average is great when you really care about the total, and want the total expressed per thing. For example, if you make 100 investments, the average return is just a way of talking about the total return on all your investments, expressed per investment. For other uses, it can be very misleading.
inetsee 4y ago
My wife worked on the project to upgrade the C-5 cargo plane's cockpit. She's 5 feet 1 inch tall, so she was chosen as the test person for the 5% end of the usability range. If she couldn't reach or operate a control in the cockpit it was a problem and the control had to be redesigned.
- swader999 4y ago
  I hope she doesn't have really long arms.
  - Hellbanevil 4y ago
- sib 4y ago
  My wife is 4'10" and often has trouble finding cars in which the driver's seat can be adjusted to fit her... I'm guessing she's well below the 5th percentile (at least in the US).
ThomPete 4y ago
My favorite example of average to illustrate how you can say something factually true, but realistically untrue "Humans on average have one testicle".
cosmojg 4y ago
I find that I want the median or the mode far more often than I want the mean. I don't understand why the latter has subsumed the former. I guess it's easier to calculate?
lbriner 4y ago
Why does this article not even once mention that average could mean "mean", "median" and/or "mode"? Even the title alludes to one of the biggest problems in the domain and that is that many people don't even realise that there is more than one way to measure an average. There are plenty of examples of where the mean is not representative of the sample and where mode or median would be more realistic, particularly where some large outliers in a relatively small sample would skew the mean.
- kibwen 4y ago
  Likely the same reason that when someone says "mean", they never bother to specify whether they're referring to the arithmetic mean, the geometric mean, or the harmonic mean. :P
- happyopossum 4y ago
  Because for the purposes of the article, it just doesn’t matter. The point is to stop distilling data down to a single point, regardless of what math term you want to use.
- asperous 4y ago
  I think because the moral of the story is the same, which is the airforce switched to customizable controls to support the range instead of over focusing on a single “average”.
- pitaj 4y ago
  For normal distributions like height, all three should be roughly equal.
vivegi 4y ago
Average by itself doesn't tell much. Average and standard deviation computed over multiple samples from the population tells a lot. Learning about the various types of standard control charts is quite useful for data-based decision making and monitoring the health of a process. Control charts and Pareto chart of root causes of defects are two of the basic tools one needs to establish 'basic stability' in a process. Basic stability is a requirement before working on improving a process.
bigmattystyles 4y ago
This reveals itself with the Carlin joke about the average person being dumb and that by implication 1/2 of the population is even dumber. Carlin and people who eagerly repeat it don’t know about distributions and that intelligence is not a standard distribution. Mea culpa, I used to parrot and believe the joke…
- programmer_dude 4y ago
  The median is also an average.
  - bigmattystyles 4y ago
    Only in a standard distribution right?
    - nostromo95 4y ago
      Any symmetrical distribution will have the mean equal the median.
      - bigmattystyles 4y ago
        But that’s the definition of a standard distribution? Intelligence is not, at least I think.
        nostromo95 4y ago
        AFAIK "standard distribution" is not a defined mathematical term; usually it's shorthand for standard normal distribution. Can't comment on intelligence distributions.
        ackfoobar 4y ago
        "standard normal distribution" is a normal distribution with mean 0 and s.d. 1. To talk about whether intelligence follows a (one-dimensional) normal distribution we have to assign a number to it. That number is usually IQ, but by design the raw score is transformed to make IQ scores follow a normal distribution. So it is trivially true. If we want to go beyond that, what does it even mean to say, for example, "twice as smart"?
hamilyon2 4y ago
And yet, 70 years afterwards, all we have is average ratings of everything, from tv shows to restaurants. Not to mention inflation, any kind of prices dynamics and wages.
- toss1 4y ago
  Yup, and the most common usage is product ratings on Amazon, which I find a complete waste of time, even before they became corrupted by massive rating-spamming. The metric I find useful is the ratio of negative (1-2 star) reviews to positive, in the product category (some categories seem to have higher usage failure rates, or POd users or something). The average is a waste of time
  - jotm 4y ago
    It's still possible to get somewhat of an accurate understanding of what you're buying if you read some reviews. I read ~10 two star reviews, ~10 four star reviews, much more depending on price. One stars tend to be full of stuff like "product hasn't arrived", "garboage", user errors. Five stars are plagued by spam and paid reviews, and also a lack of details. Three stars seem to be split between very picky buyers (esp. hate the "I paid $3.50 for this and it's not the omega particle!") and people afraid to leave lower ratings for reasons.
    - toss1 4y ago
      Agree for sure, and some good notes there! (My comment was merely limited to scope of the averages issue.) Definitely must read a decent sampling to see if there's a common problem, or it's mostly just malcontents, delivery issues, or misunderstanding the product or instructions, or just random issues. I've found in doing this that I'm usually surprised on the good side.
- deleted 4y ago
  [deleted]
- rahimnathwani 4y ago
  "all we have is average ratings of everything, from tv shows" IIRC IMDB shows mean ratings, but Rotten Tomatoes shows the % of ratings above a certain threshold. I find the latter more useful.
deleted 4y ago
[deleted]
ngc248 4y ago
"If bill gates gets on a bus, on an average everyone in the bus is a billionaire". Read this somewhere and this made me understand why just the average on its own does not say anything.
- texaslonghorn5 4y ago
  I would agree that on average each bus rider has a billion dollars, but I can't find away to justify that each person is a billionaire on average. Maybe it is because money is continuous whereas billionaire status is binary, so averaging it out doesn't really make sense.
  - cgrealy 4y ago
    Then the opposite would be true (and equally nonsensical). If billionaire is a binary status, then Gates, Musk, and Bezos could get on a bus, and on average there are no billionaires on the bus.
t_mann 4y ago
This is a poor analogy - usage statistics tend to not follow Gaussian distributions, hence the average can be a poor measure of central tendency. Body measurements usually don't have that problem, and I suppose that the average was actually used as the 'starting point', from where pilots could customize. For other distributions, one might actually prefer to opt for a different statistic altogether.
Helithumper 4y ago
If you ever check the average, always make sure to _at least_ add in the median. I don't know if there's any special syntax for this with symbols or whatever but having the median,average,and possibly even n together is way better than just the average.
lkrubner 4y ago
To bring up an issue relevant to Google and tech, this was my main criticism James Damore, and why I thought Google had grounds to fire him. The First Amendment gives him the right to write an incel-inspired manifesto if he wants to, but the misuse of "average" for political purposes makes him look like an idiot and discredits other work he might do. In his manifesto he argued that the average male is better suited to computer programming than the average female. How is that in any way relevant at Google, which only hires people 4 or 5 or 6 standard deviations away from the norm? Average isn't relevant. Bringing up the average in situations where the average is not relevant is a common mistake, but it is also a very stupid mistake. https://www.vox.com/identities/2017/8/8/16106728/google-fired-engineer-anti-diversity-memo https://www.vox.com/identities/2017/8/8/16106728/google-fire...
- 6thaccount 4y ago
- whatshisface 4y ago
  >In his manifesto he argued that the average male is better suited to computer programming than the average female. That's not what I remember it saying. Are you sure you're remembering it right?
  - dharmaturtle 4y ago
    > Women, on average, have more: > Openness directed towards feelings and aesthetics rather than ideas. Women generally also have a stronger interest in people rather than things, relative to men (also interpreted as empathizing vs. systemizing). > These two differences in part explain why women relatively prefer jobs in social or artistic areas. More men may like coding because it requires systemizing and even within SWEs, comparatively more women work on front end, which deals with both people and aesthetics. https://gizmodo.com/exclusive-heres-the-full-10-page-anti-diversity-screed-1797564320 https://gizmodo.com/exclusive-heres-the-full-10-page-anti-di...
    - whatshisface 4y ago
acjohnson55 4y ago
There's a better piece on this, which I read several years ago. The core of the problem isn't the use of the mean, which is what most of the comments are picking up on here. The problem is the Air Force was designing for the mean of more than a dozen measurements, which weren't highly correlated. In that case, even if your distributions are Gaussian, you're going to have vanishingly few samples that are on the peak on all of them, which is what the non-adjustable cockpit design optimized for. This is related to the "curse of dimensionality" https://en.m.wikipedia.org/wiki/Curse_of_dimensionality https://en.m.wikipedia.org/wiki/Curse_of_dimensionality
H8crilA 4y ago
To think that aircraft safety (military or not) improved because the cabin dimensions were adjusted is laughable. No, it was procedures and systems such as advanced autopilots, better and better ils, gps, gpws, tcas, understanding of crew resource management, textual comms like acars, better maintenance procedures, better operational procedures (even for seemingly simple tasks like deicing) ...
mmcnl 4y ago
The thing that confuses me is that the second example shows a histogram of the user activity which appears to be not a normal distribution. But for pilot dimensions, I would expect the histogram to actually follow a normal distribution. I feel the problem (and answer) of the cockpit design is presented a bit too simplistic here.
mcswell 4y ago
Probably off-topic, but: Myers Briggs seems to be based on the idea that its four properties are each dichotomous, e.g. most people are either introverted or extroverted. I would imagine that the tendency to be Y-troverted is in fact more unimodal than bimodal--if so, most people would be somewhere in the middle on most traits. Of course if the traits are not independent, that might mean that there are not many people who are in the middle on all four traits; but if they are independent, then I would expect a substantial number of people to be somewhere around average on all four traits. How broad that "somewhere around" number would be, I have no idea.
ngcc_hk 4y ago
The problem of “average” is that you try to use one statistics to rep a population. Even for bell curves you need 3 - bell curve (normal dist.), mean and std. dev. Sum up is the problem.

This also comes into play with the current discussion of EVs. People will say, "you don't need that 500 miles of range." Or, "just plug the EV in at night - you don't have to wait at the charger." That probably works well for average use cases, but not for the outliers. The great thing about ICE vehicles is you generally don't have to worry about non-average use cases. To reach parity, EVs will need to be chargable in 5 minutes from empty to achieve 500 miles of range, at 5 degrees F, with 5 year old batteries. If you live in California, that may seem like an extreme use case, but it's pretty normal around here.

gonzo41 4y ago
If the EV market could agree on a battery size and configuration, then maybe doing a full swap of a battery could be done like an f1 Pitstop. Similar to those electric scooters in Asia, Just imagine if you rolled over a pitstop and had the battery quicky taken out from below the car and then a new battery placed back in. That sort of system could change the economics of building an ev as you could move to a model where users don't really own the battery they rent it for a while until they need a swap. Or electric cargo bicycles. Because every bike on the road is one less massive car.
- cguess 4y ago
  Battery degradation would limit expectations. "Oh shit, I got one of those old batteries that will only get me 150 miles when I was hoping for 200 to get to my mother-in-law's for Thanksgiving" isn't going to work.
  - lillecarl 4y ago
    Could be solved by measuring how much charge it takes and bills you for that + some min charge for the change service would be the price, a bit more complex but I reckon the swap service could be made simple enough that it's low cost.
  - ljosifov 4y ago
    Then you are going to drive 150 miles and spend extra 3 mins to change the battery again - no? Not a big deal, and certainly not a deal breaker. Nah - the pit-stop type battery replacement is the obvious solution to most EV charging problems, but we humans can not execute it. It requires level of coordination and cooperation between companies that we are not easily capable of right now.
    - bluGill 4y ago
      Battery replacement works only if you make compromises. EVs are currently designed to put batteries where they fit, a standard battery means much less batteries and thus much less range. Second cars come in different sizes, a swappable battery needs to fit in the smallest car, leaving larger cars with a much to small battery. Sure it can work, but overall I have to call it a bad compromise.
- PaulRobinson 4y ago
  You’re making the mistake of average use cases. Your first idea requires new, expensive infrastructure that will need maintenance due to mechanical parts. Given charging points are regularly broken at the moment, I don’t have high hopes. But even if we overcame that: it’s impractical in almost every major city in the World, because you’d have to drastically alter existing spaces, such as filling stations. This might work in your context, and many others. It might even work for the “average” use case. But for 75% of the developed World (where the EV market is the fastest growing), I’m not convinced. And the electric cargo bike argument - or bikes in general - work great for the “average” journey, but not many people actually take that journey. My most frequent drive is 200+ miles in normally wet or cold weather. My next most frequent is 15+ miles in baking hot Summer sunshine in a heavily congested city where I need aircon. Neither would be pleasant on a bike - electric or not. And I think that’s the point of this discussion: engineering for averages is a terrible idea, and most EVs don’t work for most journey profiles for most of the World’s drivers today, compared to ICE
- spoonjim 4y ago
  I don’t think this will ever happen. You will need to inventory $30,000 parts to sell them for $30,005 (if $5 is the cost of the charge). And the cars will have to have tons of design compromises.
- giaour 4y ago
  There was an Israeli startup that tried this out ~10 years ago: https://jalopnik.com/battery-swapping-israeli-startup-better-place-is-dead-510139169 https://jalopnik.com/battery-swapping-israeli-startup-better... One problem was that they had chosen one model of car to simplify battery inventory, but the car was not a good fit for their initial markets.
- nradov 4y ago
  Nio is doing battery swapping successfully with their EVs in China. https://www.nio.com/blog/current-state-ev-battery-swapping https://www.nio.com/blog/current-state-ev-battery-swapping
- Hellbanevil 4y ago
CogitoCogito 4y ago
EVs don't need to entirely displace ICEs. Many zealots think so, but it isn't even necessary from an environmental perspective. But I think the main complication comes to ownership. Are you going to own an EV and an ICE? Or are you doing to own and EV and rent an ICE when needed? Or the other way around? And even if you rent it can become complicated. Last weekend I rented a car and it needed to be an EV since I booked it late and that's all that was late. I personally would rather not have dealt with the extra complexity of charging it compared to just putting gas in the tank. But really I thin the issue is that if we move to EVs it kind of forces some sort of vehicle specialization where it previously didn't feel as necessary. That opens a big can of worms when it comes to changes in lifestyle for many people.
- bluGill 4y ago
  I'm surprised you can rent an EV. Few hotels have a place to charge them, so there goes the idea of plugging them in overnight, which is the main advantage of EVs
  - zoover2020 4y ago
    In the US maybe. Lot's of countries which offer charge capabilities for EVs everywhere, even at hotels (The Netherlands, Norway etc.).
    - hef19898 4y ago
      I've even seen fast chargers at petrol stations in Tunsia this year, all the way down in the South not to far from the Lybian border.
  - chrisseaton 4y ago
    You can go to a normal super-charger while you have breakfast or whatever.
- AnIdiotOnTheNet 4y ago
  You know what else is going to open a big can of worms when it comes to changes in lifestyle for many people? Climate change.
ajconway 4y ago
Alternatively, the charging infrastructure needs to evolve. Even considering the currently available technology, imagine having 150kW chargers in place of every gas station that we have right now. Install ~20 chargers in the most busy locations, and the average time spent at the station will no be much higher than getting gas.
formerly_proven 4y ago
Frankly I do not want to share streets with people who drive 800 km, refuel and drive even more after that in one go.
- qikInNdOutReply 4y ago
  [flagged]
- jmillikin 4y ago
  There's a joke that goes something like "To an American 200 years is a long time, to a European 200km is a long distance". Driving from San Diego to Sacramento is about 800km; in good weather and light traffic you could cover that in 7 or 8 hours. Get up early, drive that first leg, stop for lunch, then keep going (e.g. towards Portland or Seattle). Of course, an American would usually stop for gas before hitting empty because we're used to the idea of "No food or fuel next 2 hours".
  - jfk13 4y ago
    A couple of decades ago, when I was young(er) and (more) foolish, I several times did the drive between Columbia, SC and Dallas, TX in a single day. It was just a touch over a thousand miles. Idiocy.
    - k__ 4y ago
      My grandfather drove us to holiday from Germany to Spain every year. Took 2-3 days. He slept a few hours in the car at night.
    - h2odragon 4y ago
      I once did a whirlwind trip from TN to NM, UT, CO, and back to TN. 5,000+ miles in 5 days. Average speed over 40MPH with some sleep and some meetings included. Idiocy, indeed.
  - ghaff 4y ago
    7 or 8 hours is a pretty long day driving for one person. But people do switch off and, even in New England where distances tend to be shorter, a 5 hour drive up to somewhere like Maine is hardly exceptional.
Andys 4y ago
I thought this until I looked at the histogram of private car trip lengths. The vast majority of trips are very short. Its unlikely they're all being done on the same day.
- tomohawk 4y ago
  Next time you have to bug out because there's a hurricane coming, and it's after your commute, so you haven't had time to charge the car, are you going to be regretting your choice? It's 95F out, humid, and your car AC is going full bore as you creep along in traffic to get out of the area. Yes, that is not an average situation, but there's a lot of peace of mind not having to think about it at all. By the time I get down to 250 miles in my ICE, I can fill up in 5 minutes, but still have a very comfortable margin for anything that may happen. And, worst case, if I run out of gas (never happened in my lifetime)? I can get a gallon of fuel and drive away. How does that work with an EV?
  - k__ 4y ago
    Sounds like a very US specific problem to me.
    - seansmccullough 4y ago
      A reasonable US-specific problem. EV limitations like this are are why millions of people aren't currently interested in buying EVs. Compared to ICE, and EV car is more expensive, and essentially has the "road trip" feature removed.
namdnay 4y ago
I think the main mistake as concerns EVS (and many other environmental questions) is the belief that tomorrow will have exactly the same comforts as yesterday. If having to wait 45mn every 400km is the biggest price you’re paying for the carbon transition, you’re very lucky

cm2187 4y ago

The other massive misuse of average I keep hearing is people referring to the life expectancy at the XVIII century. Yeah it was 40 something but not because it was very rare for people to reach 60, but because the average is dragged down by the high infant mortality rate. Once you reached 20, your life expectancy was a bit lower than today, but it was common for people to reach 60. And in general people are really bad at thinking in term of distributions. If you discuss averages or percentiles, people identify to that metric like if it applied to every individual of that distribution. That makes the debate on D&I particularly unproductive.

mdp2021 4y ago
It is helpful to say that at first quintile they died at around 10 years of age and at last quintile they died at around 70 (with a median at 33). The average may remain 40, but you get a better idea of the distribution.
elephant_burger 4y ago
To your point, the global “average” life expectancy since the 1700s to today visualized https://ourworldindata.org/grapher/life-expectancy?tab=chart&time=1770..2019&country=Africa+Asia+Europe+OWID_WRL+Americas+Oceania https://ourworldindata.org/grapher/life-expectancy?tab=chart...
- bigDinosaur 4y ago
  How to mislead with data 101!
  - jwlit 4y ago
    Indeed, though see the article linked at the bottom of that one, which goes into more of the nuance and has distribution curves etc: https://ourworldindata.org/life-expectancy-how-is-it-calculated-and-how-should-it-be-interpreted https://ourworldindata.org/life-expectancy-how-is-it-calcula...
jarenmf 4y ago

kqr 4y ago

The other common misuse of averages I keep hearing confusing "the average X" with "the X of the average Y". (Known formally as Jensen's inequality.) So for example, the average time to review a code change is not the same as the time it takes to review a code change of average size. The average user experience of a website is not given by the user experience of the average response time. And so on. People tend to compute the average of an easier variable and then forget that the derived value of interest is often nonlinear in the easier variable.

hackernewds 4y ago
very interesting. what is the suggested correct way then?
- kqr 4y ago
  Draw a random sample of easy variables from the underlying distribution, compute the variable of interest on all of those, then average.
blt 4y ago
Nit: Jensen's inequality only applies when the "derived value of interest" is a convex function of the "easier variable".

Foomf 4y ago

I absolutely love this article, and I like to re-read it every once in a while. It talks about the same thing: https://www.thestar.com/news/insight/2016/01/16/when-us-air-force-discovered-the-flaw-of-averages.html https://www.thestar.com/news/insight/2016/01/16/when-us-air-...

elephant_burger 4y ago
Thank you for sharing. This is the first chapter from Todd Rose's excellent book The End of Average. In the book, he also touches on the fascinating topic of context. For example there is no such thing as a person's average level of aggression - IF I am around my parents I tend to get aggressive, but IF I am around friends and strangers I am calm. https://www.penguin.com.au/books/the-end-of-average-9780141980034 https://www.penguin.com.au/books/the-end-of-average-97801419...
- giardini 4y ago
  FWIW the face of the statue of the "the typical woman 'Norma'" at https://www.thestar.com/news/insight/2016/01/16/when-us-air-force-discovered-the-flaw-of-averages.html https://www.thestar.com/news/insight/2016/01/16/when-us-air-... resembles Dana Scully of The X-Files. I also enjoyed Todd Rose's book, which examines the history of (mis-)interpretations and (mis-)uses of the "average": The End of Average https://www.amazon.com/End-Average-Unlocking-Potential-Embracing/dp/0062358375 https://www.amazon.com/End-Average-Unlocking-Potential-Embra...
  - leoc 4y ago
    Even Rose's article (I haven't read his book yet so I can't really say about that) tiptoes around what was going on here. It wasn't just a naive application of statistics. Rose gets through the Norma story without mentioning eugenics once, but the whole episode is so obviously part of America's pre-WWII eugenics swoon. Beyond specific beliefs about politics, race or genetics, but linked to them, there was a whole Zeitgeist, the collectivist spirit of the age that gave us Busby Berkeley musical numbers https://www.youtube.com/watch?v=ysvQ5MaUbd8 https://www.youtube.com/watch?v=ysvQ5MaUbd8 and the IBM company songbook https://www.networkworld.com/article/2333702/a-history-of-singing-the-big-blues.html https://www.networkworld.com/article/2333702/a-history-of-si... . This was a time when it was acceptable, indeed it was progressive, to be violently hostile to difference or defectiveness: see for example War Against the Weak https://waragainsttheweak.com/ https://waragainsttheweak.com/ and, maybe most especially, The Black Stork https://global.oup.com/academic/product/the-black-stork-9780195077315 https://global.oup.com/academic/product/the-black-stork-9780... . And of course it's no coincidence that the pioneers of statistics tended to be particular fans of eugenics themselves. (I am not an expert on anything.)

_the_inflator 4y ago

Also have a look at Anscombe's Quartet to get literally an overview, what averages can mean: https://en.wikipedia.org/wiki/Anscombe%27s_quartet https://en.wikipedia.org/wiki/Anscombe%27s_quartet

jimhefferon 4y ago

Another interesting, and very readable, article on the subject is What does the mean really mean? https://arxiv.org/abs/2003.01973 https://arxiv.org/abs/2003.01973

robg 4y ago

Probability and statistics should have already replaced algebra and calculus in modern education. People are just really bad at understanding variance and the impacts on what we think we know.

BurningFrog 4y ago
My gut feeling is that the education sector is extremely conservative and keeps teaching whatever is has always teached. This is one argument for homeschooling, I guess.
- solardev 4y ago
  Anecdata (I wanted to be a teacher earlier on until I actually met a few and heard their stories): Teachers are generally pretty progressive (both in the political and innovation senses), but the legislation (like Common Core), state & district educational standards, and school boards move more slowly. And in the US, the primary schools are largely funded and overseen by local parents (municipal and state), so the school priorities and cultures partially reflect local priorities. There's often debate between what individual teachers want to teach (a product of their individual preferences and backgrounds and values) vs what the administration forces them to teach (as a reflection of the political and business realities of their particular school). There's often a personality difference between the two classes too (educators vs admin types), with the former often being (at a stereotype) starry-eyed idealists and the latter being grounded management types with an eye on the numbers of finance and politics; on top of that, there is also often a labor vs mgmt (not quite "owners") divide, with individual teachers being pretty much powerless to teachers' unions being really strong in some districts. Long story short, teachers can't unilaterally change the curricula they teach. The power struggles affect everything from math (new math, math wars, whether to test it, etc.) to social studies (CRT, Native studies, bilingualism, religious studies) to science (evolution, climate) to business needs (cursive vs typing, algorithms or letterheads), etc. Far from being a settled matter, our educational system is heavily political and its lack of progress is probably reflective of our divisiveness as a country, where two broad sides keep playing tug-of-war and veering towards the extremes, making tiny gains and losses back and forth. The kids end up caught in the crossfire. The US, for all the money we pour into education, ends up rather poorly educating its children vs other developed nations: https://en.wikipedia.org/wiki/Programme_for_International_Student_Assessment#PISA_2018_ranking_summary https://en.wikipedia.org/wiki/Programme_for_International_St...

AdrianB1 4y ago

The article is a short, low quality version of the previous several ones that were explaining in detail the history, the changes, the results. It does not belong here.

leoc 4y ago
Yes, compared to Todd Rose's own article telling the story https://www.thestar.com/news/insight/2016/01/16/when-us-air-force-discovered-the-flaw-of-averages.html https://www.thestar.com/news/insight/2016/01/16/when-us-air-... this feels like a bland summary. Mind you, even Rose's version waters things down quite a bit: https://news.ycombinator.com/item?id=31961179 https://news.ycombinator.com/item?id=31961179 .

qalmakka 4y ago

There was this Roman poet, Trilussa, which created a good description of why averages are bad, which is known in Italy as "Trilussa's Chicken" Roughly translated, it goes as follows: "Following the current statistics, it turns out you're expected to be able to eat one chicken per year, and, if you can't afford it, it goes into the average anyway, because there's someone else out there eating two".

HideousKojima 4y ago
The average human has one breast and one testicle (give or take a fraction).
Phiwise_ 4y ago
Rome had a conception of statistics? That's very interesting. I'd always been told that it was a relatively new science coming from french aristocracy gambling or something.
- mdp2021 4y ago
  Carlo Salustri, artistically signing with the anagram Trilussa, died in 1950.
- GavinMcG 4y ago
  I too read "Roman" to refer to empire. Maybe because of the Latin-sounding single name, or maybe because I'm used to identifying people by their nationality rather than their city.
- qalmakka 4y ago
  Sorry, it's modern Roman, not ancient. Trilussa wrote in Romanesco, which is a Central Italian dialect (Tuscan and central Italian form a somewhat of a linguistical continuum, while southern Italian and northern languages are not mutually intelligible).
huachimingo 4y ago
It is the same as Nicanor Parra's: There are two pieces of bread. You eat two. I eat none. Average consumption: one bread per person

martincmartin 4y ago

Average is great when you really care about the total, and want the total expressed per thing. For example, if you make 100 investments, the average return is just a way of talking about the total return on all your investments, expressed per investment. For other uses, it can be very misleading.

inetsee 4y ago

My wife worked on the project to upgrade the C-5 cargo plane's cockpit. She's 5 feet 1 inch tall, so she was chosen as the test person for the 5% end of the usability range. If she couldn't reach or operate a control in the cockpit it was a problem and the control had to be redesigned.

swader999 4y ago
I hope she doesn't have really long arms.
- Hellbanevil 4y ago
sib 4y ago
My wife is 4'10" and often has trouble finding cars in which the driver's seat can be adjusted to fit her... I'm guessing she's well below the 5th percentile (at least in the US).

ThomPete 4y ago

My favorite example of average to illustrate how you can say something factually true, but realistically untrue "Humans on average have one testicle".

cosmojg 4y ago

I find that I want the median or the mode far more often than I want the mean. I don't understand why the latter has subsumed the former. I guess it's easier to calculate?

lbriner 4y ago

Why does this article not even once mention that average could mean "mean", "median" and/or "mode"? Even the title alludes to one of the biggest problems in the domain and that is that many people don't even realise that there is more than one way to measure an average. There are plenty of examples of where the mean is not representative of the sample and where mode or median would be more realistic, particularly where some large outliers in a relatively small sample would skew the mean.

kibwen 4y ago
Likely the same reason that when someone says "mean", they never bother to specify whether they're referring to the arithmetic mean, the geometric mean, or the harmonic mean. :P
happyopossum 4y ago
Because for the purposes of the article, it just doesn’t matter. The point is to stop distilling data down to a single point, regardless of what math term you want to use.
asperous 4y ago
I think because the moral of the story is the same, which is the airforce switched to customizable controls to support the range instead of over focusing on a single “average”.
pitaj 4y ago
For normal distributions like height, all three should be roughly equal.

vivegi 4y ago

Average by itself doesn't tell much. Average and standard deviation computed over multiple samples from the population tells a lot. Learning about the various types of standard control charts is quite useful for data-based decision making and monitoring the health of a process. Control charts and Pareto chart of root causes of defects are two of the basic tools one needs to establish 'basic stability' in a process. Basic stability is a requirement before working on improving a process.

bigmattystyles 4y ago

This reveals itself with the Carlin joke about the average person being dumb and that by implication 1/2 of the population is even dumber. Carlin and people who eagerly repeat it don’t know about distributions and that intelligence is not a standard distribution. Mea culpa, I used to parrot and believe the joke…

programmer_dude 4y ago
The median is also an average.
- bigmattystyles 4y ago
  Only in a standard distribution right?
  - nostromo95 4y ago
    Any symmetrical distribution will have the mean equal the median.
    - bigmattystyles 4y ago
      But that’s the definition of a standard distribution? Intelligence is not, at least I think.
      - nostromo95 4y ago
        AFAIK "standard distribution" is not a defined mathematical term; usually it's shorthand for standard normal distribution. Can't comment on intelligence distributions.
        ackfoobar 4y ago
        "standard normal distribution" is a normal distribution with mean 0 and s.d. 1. To talk about whether intelligence follows a (one-dimensional) normal distribution we have to assign a number to it. That number is usually IQ, but by design the raw score is transformed to make IQ scores follow a normal distribution. So it is trivially true. If we want to go beyond that, what does it even mean to say, for example, "twice as smart"?

hamilyon2 4y ago

And yet, 70 years afterwards, all we have is average ratings of everything, from tv shows to restaurants. Not to mention inflation, any kind of prices dynamics and wages.

toss1 4y ago
Yup, and the most common usage is product ratings on Amazon, which I find a complete waste of time, even before they became corrupted by massive rating-spamming. The metric I find useful is the ratio of negative (1-2 star) reviews to positive, in the product category (some categories seem to have higher usage failure rates, or POd users or something). The average is a waste of time
- jotm 4y ago
  It's still possible to get somewhat of an accurate understanding of what you're buying if you read some reviews. I read ~10 two star reviews, ~10 four star reviews, much more depending on price. One stars tend to be full of stuff like "product hasn't arrived", "garboage", user errors. Five stars are plagued by spam and paid reviews, and also a lack of details. Three stars seem to be split between very picky buyers (esp. hate the "I paid $3.50 for this and it's not the omega particle!") and people afraid to leave lower ratings for reasons.
  - toss1 4y ago
    Agree for sure, and some good notes there! (My comment was merely limited to scope of the averages issue.) Definitely must read a decent sampling to see if there's a common problem, or it's mostly just malcontents, delivery issues, or misunderstanding the product or instructions, or just random issues. I've found in doing this that I'm usually surprised on the good side.
deleted 4y ago
[deleted]
rahimnathwani 4y ago
"all we have is average ratings of everything, from tv shows" IIRC IMDB shows mean ratings, but Rotten Tomatoes shows the % of ratings above a certain threshold. I find the latter more useful.

deleted 4y ago

[deleted]

ngc248 4y ago

"If bill gates gets on a bus, on an average everyone in the bus is a billionaire". Read this somewhere and this made me understand why just the average on its own does not say anything.

texaslonghorn5 4y ago
I would agree that on average each bus rider has a billion dollars, but I can't find away to justify that each person is a billionaire on average. Maybe it is because money is continuous whereas billionaire status is binary, so averaging it out doesn't really make sense.
- cgrealy 4y ago
  Then the opposite would be true (and equally nonsensical). If billionaire is a binary status, then Gates, Musk, and Bezos could get on a bus, and on average there are no billionaires on the bus.

t_mann 4y ago

This is a poor analogy - usage statistics tend to not follow Gaussian distributions, hence the average can be a poor measure of central tendency. Body measurements usually don't have that problem, and I suppose that the average was actually used as the 'starting point', from where pilots could customize. For other distributions, one might actually prefer to opt for a different statistic altogether.

Helithumper 4y ago

If you ever check the average, always make sure to _at least_ add in the median. I don't know if there's any special syntax for this with symbols or whatever but having the median,average,and possibly even n together is way better than just the average.

lkrubner 4y ago

To bring up an issue relevant to Google and tech, this was my main criticism James Damore, and why I thought Google had grounds to fire him. The First Amendment gives him the right to write an incel-inspired manifesto if he wants to, but the misuse of "average" for political purposes makes him look like an idiot and discredits other work he might do. In his manifesto he argued that the average male is better suited to computer programming than the average female. How is that in any way relevant at Google, which only hires people 4 or 5 or 6 standard deviations away from the norm? Average isn't relevant. Bringing up the average in situations where the average is not relevant is a common mistake, but it is also a very stupid mistake. https://www.vox.com/identities/2017/8/8/16106728/google-fired-engineer-anti-diversity-memo https://www.vox.com/identities/2017/8/8/16106728/google-fire...

6thaccount 4y ago
whatshisface 4y ago
>In his manifesto he argued that the average male is better suited to computer programming than the average female. That's not what I remember it saying. Are you sure you're remembering it right?
- dharmaturtle 4y ago
  > Women, on average, have more: > Openness directed towards feelings and aesthetics rather than ideas. Women generally also have a stronger interest in people rather than things, relative to men (also interpreted as empathizing vs. systemizing). > These two differences in part explain why women relatively prefer jobs in social or artistic areas. More men may like coding because it requires systemizing and even within SWEs, comparatively more women work on front end, which deals with both people and aesthetics. https://gizmodo.com/exclusive-heres-the-full-10-page-anti-diversity-screed-1797564320 https://gizmodo.com/exclusive-heres-the-full-10-page-anti-di...
  - whatshisface 4y ago

acjohnson55 4y ago

There's a better piece on this, which I read several years ago. The core of the problem isn't the use of the mean, which is what most of the comments are picking up on here. The problem is the Air Force was designing for the mean of more than a dozen measurements, which weren't highly correlated. In that case, even if your distributions are Gaussian, you're going to have vanishingly few samples that are on the peak on all of them, which is what the non-adjustable cockpit design optimized for. This is related to the "curse of dimensionality" https://en.m.wikipedia.org/wiki/Curse_of_dimensionality https://en.m.wikipedia.org/wiki/Curse_of_dimensionality

H8crilA 4y ago

To think that aircraft safety (military or not) improved because the cabin dimensions were adjusted is laughable. No, it was procedures and systems such as advanced autopilots, better and better ils, gps, gpws, tcas, understanding of crew resource management, textual comms like acars, better maintenance procedures, better operational procedures (even for seemingly simple tasks like deicing) ...

mmcnl 4y ago

The thing that confuses me is that the second example shows a histogram of the user activity which appears to be not a normal distribution. But for pilot dimensions, I would expect the histogram to actually follow a normal distribution. I feel the problem (and answer) of the cockpit design is presented a bit too simplistic here.

mcswell 4y ago

Probably off-topic, but: Myers Briggs seems to be based on the idea that its four properties are each dichotomous, e.g. most people are either introverted or extroverted. I would imagine that the tendency to be Y-troverted is in fact more unimodal than bimodal--if so, most people would be somewhere in the middle on most traits. Of course if the traits are not independent, that might mean that there are not many people who are in the middle on all four traits; but if they are independent, then I would expect a substantial number of people to be somewhere around average on all four traits. How broad that "somewhere around" number would be, I have no idea.

ngcc_hk 4y ago

The problem of “average” is that you try to use one statistics to rep a population. Even for bell curves you need 3 - bell curve (normal dist.), mean and std. dev. Sum up is the problem.