
The Evolution of Trust - awartani
http://ncase.me/trust/
======
cryptica
Wow that is extremely insightful.

Now I understand why globalisation is dangerous; if people start to favor
short term relationships (both personal and business) with many different
partners (smaller number of rounds <interactions> per match <lifetime>), then
society will evolve to become full of cheaters.

~~~
sgk284
Interestingly enough, seemingly to compensate for this phenomenon, almost
every new platform that requires people to interact with each other has a
built in trust and reward system with ratings (e.g. Uber).

And for physical businesses, we have things like Yelp. We are effectively
trying to anticipate our opponents behavior through a trusted intermediary.

There was a Black Mirror episode on giving every person on the globe their own
rating. It seems that may be the actual destination that we're headed for.

~~~
cJ0th
Trust, however, is not a miracle drug.

For one thing, people can build trust with the intend to abuse it after a
longer period of time. An abuser, for example, could plan to offer 20 "good
rides" on Uber until s/he strikes. For another thing, many people have learnt
to skillfully simulate trust which may pose a problem for you. For instance,
you may believe to be in a loving relationship but all of a sudden you find
out that the other person isn't interested in you at all and just didn't want
to be alone etc.

~~~
rossdavidh
The book "Phishing for Phools" has a good chapter on "reputation mining",
which is essentially that, with the added wrinkle that you can buy a company
that has a good reputation and cut corners until the customers wise up. I'm
looking at you, InBev.

~~~
rout39574
I believe the term of art is "Extracting the value from the brand".

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sfsylvester
This is by far one of the coolest things I've seen on this site.

Informative, engaging and educational. Would be very keen to learn more
subjects through this method.

~~~
conradev
Nicky Case has a lot more where that came from :D

[http://ncase.me](http://ncase.me)

~~~
CupOfJava
Wow. I played "we become what we behold" just last week. I had no idea it was
the same author. I'm gonna check out the rest now too!

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j2kun
Of course, this all breaks down when you have a cartel :) I recall in one of
the major prisoners dilemma tournaments, the winning entry was actually a
coalition of users who would use the first few moves to establish a code for
membership in the cartel, and then one entry was the master while the others
were slaves. The slaves always cooperated and the master always defected, to
their victory.

~~~
s_kilk
Indeed, the major weakness of the linked piece is that it doesn't account for
any kind of social structure or any class behaviour. Which, in my book, makes
it fairly worthless as an analysis of actual social behaviour.

~~~
09094920394314
Not worthless. This has some clear assumptions on what holds. He looks at
individuals playing a certain game, with no outside information. What the
parent describes is two games: 1. Prisoners dilemma between each "slave" and
the "master" 2\. The actual tournament

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freeflight
This is great and really fun.

10 rounds with changed payoffs has some really interesting results. Punishing
cheating from both sides, regardless of how high, still leads to the cheaters
taking over. But if you increase the payoffs for both sides cooperating, even
if it's just by +1, you already eliminate all the cheaters very quickly and
even the copycats are gone pretty quick, leaving a population of only
cooperate.

Sure that's for the 10 round game without any of the other players, it's still
very interesting how even in that setting it seems more beneficial to reward
good behavior vs punishing bad behavior.

------
hftf
The execution of this visualization was rather disappointing.

I didn’t like the overly cute text (the description of the Simpleton algorithm
was almost incomprehensible), the low-contrast captions and colorblind-
unfriendly color scheme, and the limited navigation (there was no way to go to
the previous slide within a chapter, for example).

But more importantly: If you are going to design an entire interactive
exercise like this, graphs are a much better way to explore the effects of
varying different parameters. Trying to experiment (as instructed) with
different parameters by watching animations in the various chapters and the
"sandbox mode" included in this simulation was not only tedious, but prevented
effective comparisons. If you just run each iterated tournament (from chapter
4 and onwards) by pressing the "Start" button, there is too much going on
simultaneously at a high speed to follow along – I would recommend a sorted
table or bar chart rather than many multi-digit numbers arranged in a circle –
while stepping through is too slow to keep everything in your head.

I noticed that some of the other "explorable explanations" by the same creator
include graphs; I think omitting them from this visualization was a mistake.
[http://explorableexplanations.com/](http://explorableexplanations.com/)

------
mLuby
Very cool simulation.

Would love to see it with inter-agent communication between rounds, where
those you cooperate with tell you who cheated them.

------
arca_vorago
This caught my attention:

"So, it seems the math of game theory is telling us something: that Copycat's
philosophy, "Do unto others as you would have them do unto you", may be not
just a moral truth, but also a mathematical truth."

Simpleton and copykitten for the win!

~~~
DanAndersen
I also found it interesting how the success of cheaters requires a limited
number of interactions (so their opponents don't catch on that they are
cheaters). Perhaps that's why certain occupations such as used car salesmen
have a reputation for being sleazy -- most people are not buying cars very
often and so don't get the chance to get to know an individual seller over the
course of many transactions. So while you might know that the corner-store
merchant is screwing you and end up avoiding him, the used car salesman has a
steady stream of suckers who don't know him.

~~~
dredmorbius
Used car sales has its direct antecedents in horse trading and dealing.

There was a famous-for-its-time story called _David Harum_ , (1899), made into
a film in 1915, and a radio serial in the 1950s. Its principle legacy today is
the use of the term "horse trading" to mean "underhanded dealing".

[https://en.m.wikipedia.org/wiki/David_Harum](https://en.m.wikipedia.org/wiki/David_Harum)

I'd run across it via H.L. Mencken's essay, "Bayard v. Lionheart", itself best
recalled for its concluding sentence:

 _As democracy is perfected, the office represents, more and more closely, the
inner soul of the people. We move toward a lofty ideal. On some great and
glorious day the plain folks of the land will reach their heart 's desire at
last, and the White House will be adorned by a downright moron._

... but containing oh so much more, in the foil of a critique of the 1926 U.S.
Presidential Election. Really, read it:

[http://amomai.blogspot.com/2008/10/hl-mencken-bayard-vs-
lion...](http://amomai.blogspot.com/2008/10/hl-mencken-bayard-vs-
lionheart.html)

Both used cars and horses have several characteristics in common:

* They are anti-commodities. That is, individual items for sale are highly disuniform, complex, and not readily assessed.

* They are expensive. For the ordinary consumer, they are not purchases likely to be made frequently. (A horse and a car each have fairly equivalent useful working lives: about 3-10 years, depending on use and care afforded.)

* Sellers of quality instances are much inclined to stay away from the general market. It's a case where selling to someone who is specifically aware of the qualities of what you're selling is a far better customer.

This has other cognates. Software and consulting services come to mind.

The treatment in the economic literature is somewhat disappointing. There's
Ackerloff's "The Market for Lemons", of course (won him a Nobel prize), but
it's a generally underserved area of theory.

------
Rjevski
> Despite strict orders not to chillax with the enemy, British and German
> soldiers left their trenches, crossed No Man's Land, and gathered to bury
> their dead, exchange gifts, and play games.

Is this actually true? I'd love to read more about it.

~~~
clock_tower
Absolutely true:
[https://en.wikipedia.org/wiki/Christmas_truce](https://en.wikipedia.org/wiki/Christmas_truce)

~~~
Rjevski
Thanks - that was a heart-warming read.

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bmc7505
The creator of this project has a really amazing talk about his work,
including interactive explainers, narrative games and chaos theory. Really
interesting:
[https://www.youtube.com/watch?v=Zl9m0AQInBk](https://www.youtube.com/watch?v=Zl9m0AQInBk)

------
egonschiele
This is super impressive. I have been asking myself these questions for
_years_ , it is awesome to see such a nice visualization of the answers. The
"30 minutes to play" almost made me click away but you got me hooked at the
next screen.

------
ybaumes
I've read it multiple times, I still do not understand the simpleton
strategy...

~~~
Rudism
Essentially, the simpleton is treating your previous move as either a reward
or punishment.

If you cooperated, then the simpleton thinks the thing it did last time must
have been good and does it again. If you cheated, the simpleton thinks the
thing it did last time must have been bad and does the opposite.

It follows these rules based on its last move even if that last move was
flipped from what it should have been due to the chance of mistake.

------
DanAndersen
One extension I'd like to see to this simulation is the exploration of
group/tribe dynamics, as a way of exploring questions regarding in-group
loyalty (anthropomorphized in as "ethnocentrism" or something analogous) vs
egalitarianism. It seems like much of the success of these agents can depend
on whether Agent A can determine what sort of actor Agent B is --
communication that can be conveyed beyond just the framework of actual
transactions between A and B.

Are there any existing generic frameworks out there for testing out a wider
range of agent/group-based game theory scenarios?

~~~
dwaltrip
Another important missing factor here is the modeling of empathy and altruism.
It can often simply _feel good_ to help someone else, even if you get nothing
tangible in return. This is a biological fact, as far as I'm aware.

Incredibly crude approximation: some situations that appear as [empathetic
helper +0, receiver +3] on the surface, might in reality be [empathetic helper
+1, receiver +3].

There is a ton of complexity in how this works in the real world. The
magnitude or presence of the non-tangible reward may depend heavily on a
certain aspects of one's value system. It may be heavily contextual -- only
certain situations foster the non-tangible reward. Sometimes there is a
potential tangible reward that may come much later, after some weeks, months,
or years. And so on... I think this is barely scratching the surface.

Lastly, none of the people or dynamics in the system are static.

The linked interactive tool was very cool. However, I'm increasingly skeptical
of these types of analyses as they generally are forced to ignore most of the
complexity of the real world.

EDIT: I completely forgot about technology... things like the internet which
completely change the nature of an interaction between people, or apps that
mediate or flavor in-person interactions in ways that society has never seen
before.

~~~
barrkel
Have you thought that perhaps things like emotions, both empathy and revenge
have evolved to emulate Copycat / Copykitten play styles?

That is, I don't think they're missing from the simulation. Rather, the
simulation shows why those things exist.

------
crawfordcomeaux
"Nonviolent Communication" by Marshall Rosenberg teaches a structured
framework enshrining the takeaways from this lovely bit of art.

------
trhway
From Netflix's "Sense8" :

What is the advantage of the Homo Sapiens over the Homo Sensorium (the
telepathic humans)?

Homo Sapiens is capable of lying.

------
RonanTheGrey
We like to think we are complex, free-will wielding creatures capable of doing
complex and unpredictable things.

It's striking to see how simple we really are and honestly - how easy it is to
explain how we behave. I get it - this is a simulation and it leaves out alot
of colors to human behavior. But it is the essence of our value-oriented
decision making and really quite sad that a better world is actually? quite
easy to make.

I think software has the potential to create that world. I propose the
creation of a formal group dedicated to exactly such a purpose.

------
udkl
As a co-incidence, I just read this relevant article today -
[http://www.economist.com/news/economics-
brief/21705308-fifth...](http://www.economist.com/news/economics-
brief/21705308-fifth-our-series-seminal-economic-ideas-looks-nash-equilibrium-
prison)

Edit : to say - This site was a beautiful insightful experience.

------
roflc0ptic
More reading on this: There is a paper by David Axelrod and W.D. Hamilton
called "The Evolution of Cooperation". There is also a book by Axelrod of the
same name.

[https://en.wikipedia.org/wiki/The_Evolution_of_Cooperation](https://en.wikipedia.org/wiki/The_Evolution_of_Cooperation)

------
cryptonector
This blew up on reddit:
[https://www.reddit.com/r/philosophy/comments/6q1i1e/game_the...](https://www.reddit.com/r/philosophy/comments/6q1i1e/game_theory_and_the_golden_rule/)

------
minademian
this is incredibly fascinating and insightful.

side question: who composed the music? the guitar track is excellent. :)

~~~
dentarg
there's a list of music/sound credits on the github page:
[https://github.com/ncase/trust/#play-it-here-
httpncasemetrus...](https://github.com/ncase/trust/#play-it-here-
httpncasemetrust)

------
hellbanner
27 points, how'd you do HN?

------
tpeo
The little animated chums strike me be as a bit _too_ cute.

One has to take care to not anthropomorphize models. Even models ostensibly
created to model aspects of human behavior, such game theoretic models.

Anthropomorphism might induce people either to think there's more under the
hood than there actually is, and thus lead them to a hold a wrong mental
representation of the model, or to naively assume that it's conclusions are
robust to specification changes by making the conclusions a bit _too_
familiar, even though even somewhat simple model extensions might
significantly change their behavior (e.g. going from single to repeated games,
which makes cooperatives strategies viable).

Comparing tit-for-tat strategies with the Golden rule, while mixing in
references toe the Christmas truce somehow seems to go in the opposite
direction of being cautious regarding model interpretation.

~~~
larsiusprime
> even though even somewhat simple model extensions might significantly change
> their behavior (e.g. going from single to repeated games, which makes
> cooperatives strategies viable).

He explicitly examines this in the application, did you not run through it? He
actively encourages you to modify the rules and see how it changes the
results.

~~~
tpeo
I ran through it. I didn't suggest he didn't cover it. I just used it as a
trivial example, because other readers supposedly also ran through it. Some
other commenter suggested communication between agents as an extension, I
could've used that if I knew what results from it.

