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Re:Be Kind by endymi0n on Friday October 14, 2016 @09:25AM (#12707881)
When he returned to the air field, Bob Hoover walked over to the man who had nearly caused his death and, according to the California Fullerton News-Tribune, said: “There isn’t a man alive who hasn’t made a mistake. But I’m positive you’ll never make this mistake again. That’s why I want to make sure that you’re the only one to refuel my plane tomorrow. I won’t let anyone else on the field touch it.”
Re:Be Kind by pfarnsworth on Friday October 14, 2016 @11:15AM (#12708610)
There are two schools of thought, especially in stock trading.

1) Reversion to the mean. This is what the above person believes and that this likely won't happen again.

2) Indication of a trend. The pilot is actually incompetent, and this will happen more frequently with this pilot than an average pilot.

Re:Be Kind by wyago on Friday October 14, 2016 @12:07PM (#12709009)
I know you're probably not implying regression to the mean is causational, but that was my initial reading so I want to clarify for those who may not be familiar with the concept.

Regression to the mean is simply that any given datapoint is most likely to be the mean, or close to it. This means that any exceptional data point,up or down, can be expected to be followed up by the mean.

The example of this being misinterpreted that I am familiar with is that of a flight instructor's belief on training. When a pilot performed well, they wouldnt comment. If a pilot performed poorly, they would be punished. They believed this was better because when they praised a pilot, they would usually do worse the following run, and when they punish them they do better. This isn't technically wrong, they are just ascribing causation where there is none. I think I saw this example in Signal vs. Noise, but I'm not sure.

Basically, regression to the mean isn't a reason to pick someone who did poorly, it's a reason that that person will do no worse or better than they do normally.

Re:Be Kind by cortesoft on Friday October 14, 2016 @05:53PM (#12711373)
Yeah, I always make an example with coin flips to show how this is true.... lets say heads is success and tails is failure.

Flip 100 coins. Take the ones that 'failed' (landed tails) and scold them. Flip them again. Half improved! Praise the ones that got heads the first time. Flip them again. Half got worse :(

Clearly, scolding is more effective than praising.

Re:Be Kind by bbcbasic on Friday October 14, 2016 @06:18PM (#12711539)
That's a brilliant example. I wont forget that now.
Re:Be Kind by abhi_kr on Sunday October 16, 2016 @05:06AM (#12717733)
Except, coins are not humans with emotions, and neither can they dupe probability to improve their outcome. The 50 heads(success) that you left are not going to do any better than the 50 tails you scolded. You are just changing the sample space in a biased fashion to prove your point.
Re:Be Kind by cortesoft on Sunday October 16, 2016 @10:22PM (#12722326)
I think you are totally missing my point. The whole point I am trying to make centers on the fact that the coins are all actually equal. The observed difference in performance is entirely due to chance.

While, of course, human performance is not always equal in the same way our coins are, the fact that performance (or whatever it is you are measuring) will still regress towards the mean still holds true. The coin example just gives an extremely obvious demonstration about what is happening when things regress towards the mean.

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

Re:Be Kind by shitgoose on Saturday October 15, 2016 @11:12PM (#12716680)
hilarious! thank you!
Re:Be Kind by gbog on Friday October 14, 2016 @12:55PM (#12709395)
The pilot performance example is in Thinking Fast and Slow, I think.
Re:Be Kind by vmarsy on Friday October 14, 2016 @01:23PM (#12709619)
I've read that story in "How to win friends and influence people"

https://www.google.com/#&q=%22how+to+win+friends+and+influen...

Re:Be Kind by wyago on Friday October 14, 2016 @03:53PM (#12710627)
Ah, yeah. I think that's actually where I saw it. Thanks.
Re:Be Kind by kordless on Friday October 14, 2016 @09:19PM (#12712227)
Now if only Intel would add that to their instruction set.
Re:Be Kind by tehwalrus on Friday October 14, 2016 @12:24PM (#12709137)
Isn't regression to the mean a phenomenon of random variables?

Humans aren't perfect improvement machines, but they surely beat a random variable?!

Re:Be Kind by theptip on Friday October 14, 2016 @12:32PM (#12709196)
Correct. I think reversion to the mean is a non-sequitur here.

Neither the GP's quote, nor the OP, are making the statement "I understand that this mistake was an outlier, you'll probably never make this mistake again if you remain unchanged".

The claim being made is that acknowledging the mistake and learning from it can dramatically reduce the base probability of such mistakes happening again.

Re:Be Kind by SatvikBeri on Friday October 14, 2016 @01:42PM (#12709778)
Regression to the mean applies any time a process has high variance. If I have an unusually productive week, odds are the next week will be worse, simply because the previous one was an outlier. But people often make the mistake of noticing week X+1 was much worse than week X, and attributing it to some variable that changed between X and X+1.
Re:Be Kind by josinalvo on Friday October 14, 2016 @07:16PM (#12711770)
In my model, humans have an average performance, that increases over time (unless something terrible happens) and a random component, that makes performance fluctuate around the average.

The question is: is the day-to-day random variation much bigger than the day-to-day average increase? If so, regression towards the mean makes total sense.

Re:Be Kind by omginternets on Friday October 14, 2016 @05:35PM (#12711271)
I disagree with your interpretation. I think this is a case of understanding that the pilot is now motivated to save face, and will be extra careful.

This is psychological insight, not statistical insight.

Re:Be Kind by eevilspock on Friday October 14, 2016 @03:18PM (#12710422)
Wow, you totally missed the point of the story:

3) Out of remorse, pride, being shocked out of complacency or some combination of these, the man would do his absolute best the next day, especially for the very same pilot.

Re:Be Kind by dredmorbius on Friday October 14, 2016 @12:18PM (#12709090)
There's also differences in management and industry style.

If labour is so abundant that there's little problem in replacing any given worker, people can and will be fired for trivial offences. If there's a shortage, or there's a considerable on-boarding process, less so.

The threat of a firing-at-any-moment also makes for a more tractable workforce, at least from a management perspective.

Re:Be Kind by niccaluim on Friday October 14, 2016 @03:50PM (#12710602)
3) Experience is a series of non-fatal mistakes.

Not everything is a financial metaphor.

Re:Be Kind by MrQuincle on Saturday October 15, 2016 @07:24PM (#12716092)
3) You might argue for versions of Bayesian thought as well (full Bayesian, MAP, ML).

I think more appropriate in this context is learning though. And I would suggest here multi-armed bandits (with every arm representing a pilot).

https://en.wikipedia.org/wiki/Multi-armed_bandit

There is tradeoff between exploration and exploitation that has to be made.

The goal in this case corresponds to a particular type of bandit. It is to postpone death for as long as possible by pulling the right arm. I actually didn't find this type yet (a mortal multi-armed bandit has a birth-death process of the arms themselves).

Edit: This is only about the learning process on the non-pilot side, as one of the other commentators already articulated.

Re:Be Kind by racl101 on Friday October 14, 2016 @07:04PM (#12711734)
Totally ruined that warm feeling I got from the anecdote with your damn logic.
Re:Be Kind by patio11 on Friday October 14, 2016 @01:52PM (#12709854)
There is a perhaps apocryphal story about the time when Mizuho Securities lost ~$225 million by attempting to sell 610k shares at 1 yen instead of 1 share at 610k yen. When asked whether he intended to fire the person who physically keyed in the order, the relevant department head stated that he did not intend to waste the firm's substantial investment in teaching them to act with due deliberation.
Re:Be Kind by hughes on Friday October 14, 2016 @02:16PM (#12710047)
I wish that story ended with the developer of the trading software learning a lesson about user interfaces
Re:Be Kind by barsonme on Friday October 14, 2016 @02:27PM (#12710134)
This is a good point--I remember even the online game "Runescape" had a warning that would pop up if you tried to sell an item worth X for a very low price.

It would seem to me (somebody who knows squat about stock trading) that a warning screen would be much more beneficial for stock trading software than it is for an online video game.

Re:Be Kind by Karunamon on Friday October 14, 2016 @04:45PM (#12710964)
You'd think that, but then what happens is users get used to the warnings coming up and consciously/unconsciously adjust to click by it without reading.

I'd imagine in the case of the stock trader, where quick reaction is valued, he'd have quickly entered whatever key combo is necessary to dismiss it the warning and made the same mistake.

Re:Be Kind by laughinghan on Friday October 14, 2016 @07:51PM (#12711898)
Only if the warnings come up too often. I imagine it should be quite possible to define criteria that discriminate selling shares at a price of 0.0000016 yen from normal prices, by comparing with the market price, or the range of prices ever seen by the software, for example.

Alarm fatigue is an important design consideration, but not a reason to not put warnings at all (given that this isn't amenable to an "Undo" button, which is preferable when possible).

Re:Be Kind by cortesoft on Friday October 14, 2016 @05:55PM (#12711386)
Re:Be Kind by TuringNYC on Sunday October 16, 2016 @03:55AM (#12717544)
Alarm fatigue is indeed an issue -- but if the trader is repeatedly trying to sell for way below market price that often, then perhaps there is a much bigger problem...with the trader.
Re:Be Kind by ramchip on Friday October 14, 2016 @11:18PM (#12712569)
It ended up with order sanity checks being implemented for all manual trading systems at Mizuho. Things like blocking an order if it's more than 10% away from the market mid, etc.

You shouldn't fix an issue like this with UI validation alone - it needs to go between the component that creates orders and the stock exchange, so that it also protects against software bugs. For instance, a possible bug is a developer multiplying the order size by the lot size in the backend, when it has already been multiplied in the frontend, causing huge orders to be sent. Sanity checks can catch this.

Automated trading systems have traditionally been under a lot of scrutiny, and nobody in their right mind would run one without sanity checks and a kill switch. That incident taught Mizuho that manual trading can, in fact, also be quite dangerous :)

Re:Be Kind by JoshTriplett on Friday October 14, 2016 @02:05PM (#12709942)
I've seen several versions of that story, often with the quote "Why would we fire you? We just spent $X million educating you." Probably some combination of truth and exaggeration, but it makes for a memorable story regardless.
Re:Be Kind by Arjuna on Friday October 14, 2016 @02:26PM (#12710126)
I was not familiar with this story; that prompted me to research it. I found it interesting that this aviation incident had a positive outcome, in the form of safety innovations: the Hoover Nozzle and the Hoover Ring. Wikipedia states:

"A perhaps-undesired recognition is the Hoover Nozzle used on jet fuel pumps. The Hoover Nozzle is designed with a flattened bell shape. The Hoover Nozzle cannot be inserted in the filler neck of a plane with the Hoover Ring installed, thus preventing the tank from accidentally being filled with jet fuel.

This system was given this name following an accident in which Hoover was seriously injured, when both engines on his Shrike Commander failed during takeoff. Investigators found that the plane had just been fueled by line personnel who mistook the piston-engine Shrike for a similar turboprop model, filling the tanks with jet fuel instead of avgas (aviation gasoline). There was enough avgas in the fuel system to taxi to the runway and take off, but then the jet fuel was drawn into the engines, causing them to stop.

Once Hoover recovered, he widely promoted the use of the new type of nozzle with the support and funding of the National Air Transportation Association, General Aviation Manufacturers Association and various other aviation groups (the nozzle is now required by Federal regulation on jet fuel pumps)." [1]

[1] https://en.wikipedia.org/wiki/Bob_Hoover#Hoover_Nozzle_and_H...

Re:Be Kind by eppeltert on Friday October 14, 2016 @02:31PM (#12710164)
In general, this design principle is known as poka yoke:

https://en.wikipedia.org/wiki/Poka-yoke

Re:Be Kind by Schwolop on Sunday October 16, 2016 @06:58PM (#12721556)
In terms of physical connectors, I've always referred to this as polarisation. The connector is polarised so that it can only be inserted in one orientation, generally by use of a slot and key.
Re:Be Kind by hilop on Friday October 14, 2016 @08:40PM (#12712079)
And the problem it solves is Murphy's Law: https://en.wikipedia.org/wiki/Murphy%27s_law
Re:Be Kind by pmarreck on Friday October 14, 2016 @05:26PM (#12711207)
This is a great design concept to know the name of! Thanks!
Re:Be Kind by justifier on Friday October 14, 2016 @10:12AM (#12708165)
this is a great anectdote, but the reason i am replying to your comment is because of your user name

i am a huge fan of the turn of the century dancer isadora duncan and her lover who she first had a child with, the theatre set design theorist, edward gordon craig who she affectionately called endymion

a complete aside, but if you have, or anyone reading this has, yet to read duncan's autobiography 'my life' i highly recommend it to anyone and everyone

she is a brilliant writer, lived an eccentric life, and she was and her writing is imbued with a mad passion for expression and both life's hardships and joys

Re:Be Kind by ryanmarsh on Friday October 14, 2016 @10:41AM (#12708358)
Seems like something my wife would like to read. Just bought her a copy. Thanks for the tip.
Re:Be Kind by sjcsjc on Friday October 14, 2016 @12:26PM (#12709149)
Good idea. I've just done the same. Thanks both
Re:Be Kind by tominous on Friday October 14, 2016 @11:24PM (#12712579)
I can't resist chiming in with another Endymion reference: the Hyperion Cantos by Dan Simmons. Fantastic series.
Re:Be Kind by edraferi on Friday October 14, 2016 @12:04PM (#12708991)
That is some really quality nerd stuff right there. Thanks!
Re:Be Kind by danohu on Wednesday October 19, 2016 @04:42AM (#12742139)
I'm now reading My Life because of this comment. I'm greatly enjoying it so far -- thanks!
Re:Be Kind by CuriouslyC on Friday October 14, 2016 @11:44AM (#12708837)
In my experience, while someone might be extra careful not to repeat a mistake that has burned them in the past, making a serious mistake is often a sign that someone is careless, and more likely to make other, different mistakes in the future.
Re:Be Kind by brazzledazzle on Friday October 14, 2016 @12:16PM (#12709079)
This doesn't jibe with my experience. As long as the person doesn't evaluate their mistakes in a vacuum they become more careful in general because they learn that things can bite you in the ass in totally unexpected ways.

So I'd say it depends on your environment combined with the individual. Someone who is apathetic and/or lacks critical thinking skills will probably learn very little beyond avoiding that specific mistake again.

Re:Be Kind by NoPiece on Friday October 14, 2016 @12:54PM (#12709379)
*jibe (jive is a dance, jibe is agree)
Re:Be Kind by robocat on Friday October 14, 2016 @04:36PM (#12710909)
http://www.dailywritingtips.com/gibe-gybe-jibe-and-jive/

Shows the other meanings of the homophones - English huh!

Re:Be Kind by brazzledazzle on Friday October 14, 2016 @01:35PM (#12709717)
Right you are. Thanks, I was able to edit it in time.
Re:Be Kind by smacktoward on Friday October 14, 2016 @01:44PM (#12709801)
One mistake, even one very serious mistake, means nothing. People are human, even the best of them are going to make mistakes occasionally. Be as careful as you want, it doesn't matter, literally nobody is perfect.

A pattern of making mistakes can tell you somebody is careless, or sloppy, or in over their head. But a single mistake? That's just inevitable.

Re:Be Kind by bsder on Friday October 14, 2016 @05:38PM (#12711288)
> A pattern of making mistakes can tell you somebody is careless, or sloppy, or in over their head.

Or that you need to fix the process.

Re:Be Kind by groby_b on Friday October 14, 2016 @02:57PM (#12710310)
We all make serious mistakes from time to time. Yes, you too. If you haven't yet, you will - don't worry. Nobody gets an exemption from that.

When that happens, I hope the people around you are more forgiving than you are.

Re:Be Kind by toomuchtodo on Friday October 14, 2016 @12:10PM (#12709034)
> making a serious mistake is often a sign that someone is careless, and more likely to make other, different mistakes in the future.

Or under external pressures they have no control over.

Re:Be Kind by RUG3Y on Friday October 14, 2016 @03:11PM (#12710387)
Right. I've been in a situation where I attained a huge amount of responsibility and authority in a short amount of time. I was learning a dozen new tasks simultaneously and getting something like 4 hours of sleep a night (military). I made some pretty big mistakes, and I think it's fair to assume that anyone would under those circumstances.
Re:Be Kind by toomuchtodo on Friday October 14, 2016 @03:17PM (#12710416)
Agree. Some people simply have unrealistic expectations.
Re:Be Kind by plandis on Friday October 14, 2016 @04:15PM (#12710760)
Well that's not the experience I've had at all. I bet you if you ask any senior engineer they'd tell you the numerous different ways they have really messed over their careers.

I think it's especially true in tech jobs where there is a lot learned on the job. I would be deeply skeptical of any tech company that takes a fire first attitude. That just tells me they 1) treat devs as disposable and 2) they get rid of everyone that has a chance to learn from their mistakes

Re:Be Kind by hodgesrm on Friday October 14, 2016 @05:11PM (#12711109)
It's probably not unrelated that American air travel is very safe because there's a no-blame, learn-from-the-issue attitude to problems.

More generally it is very difficult to build highly reliable systems of any kind without having a very open culture where you focus on exposing problems and fixing them rather than blaming the message.

Re:Be Kind by tomelders on Friday October 14, 2016 @07:19PM (#12711784)
I'm reminded of the time Tony Blair visited Silicon Valley to figure out how to replicate it back home. He was at a round table with tech royalty (Gates, The Sun guy, Schmidt etc etc). Steve Jobs was there too.

Everyone was chipping in with their theories about why the U.S and Silicon Valley were so good at what they do when Jobs lost his patience and butted in in true Jobsian fashion.

"Listen! Take a look around this table. Everyone here has a massive failure in their past. Big, epic failures. In the US, we think thats a good thing. In the UK you think it's a bad thing. Thats it."

Or soemthing like that, you get the idea.

Anyway, i've always liked that outlook regardless of wether it's true or not.

Re:Be Kind by huangc10 on Friday October 14, 2016 @01:48PM (#12709833)
Link to the Bob Hoover story: http://www.squawkpoint.com/2014/01/criticism/
Re:Be Kind by bgilham on Friday October 14, 2016 @09:47AM (#12708016)
Nice!