**nhaliday : characterization**
64

Software Testing Anti-patterns | Hacker News

october 2019 by nhaliday

I haven't read this but both the article and commentary/discussion look interesting from a glance

hmm: https://news.ycombinator.com/item?id=16896390

In small companies where there is no time to "waste" on tests, my view is that 80% of the problems can be caught with 20% of the work by writing integration tests that cover large areas of the application. Writing unit tests would be ideal, but time-consuming. For a web project, that would involve testing all pages for HTTP 200 (< 1 hour bash script that will catch most major bugs), automatically testing most interfaces to see if filling data and clicking "save" works. Of course, for very important/dangerous/complex algorithms in the code, unit tests are useful, but generally, that represents a very low fraction of a web application's code.

hn
commentary
techtariat
discussion
programming
engineering
methodology
best-practices
checklists
thinking
correctness
api
interface-compatibility
jargon
list
metabuch
objektbuch
workflow
documentation
debugging
span-cover
checking
metrics
abstraction
within-without
characterization
error
move-fast-(and-break-things)
minimum-viable
efficiency
multi
poast
pareto
coarse-fine
hmm: https://news.ycombinator.com/item?id=16896390

In small companies where there is no time to "waste" on tests, my view is that 80% of the problems can be caught with 20% of the work by writing integration tests that cover large areas of the application. Writing unit tests would be ideal, but time-consuming. For a web project, that would involve testing all pages for HTTP 200 (< 1 hour bash script that will catch most major bugs), automatically testing most interfaces to see if filling data and clicking "save" works. Of course, for very important/dangerous/complex algorithms in the code, unit tests are useful, but generally, that represents a very low fraction of a web application's code.

october 2019 by nhaliday

OCaml For the Masses | November 2011 | Communications of the ACM

july 2019 by nhaliday

Straight out of the box, OCaml is pretty good at catching bugs, but it can do even more if you design your types carefully. Consider as an example the following types for representing the state of a network connection as illustrated in Figure 4.

that one excellent example of using algebraic data types

techtariat
rhetoric
programming
pls
engineering
pragmatic
carmack
quotes
aphorism
functional
ocaml-sml
types
formal-methods
correctness
finance
tip-of-tongue
examples
characterization
invariance
networking
org:nat
cs
that one excellent example of using algebraic data types

july 2019 by nhaliday

Alon Amit's answer to Why is there no formal definition for a set in math? How can we make any statement about sets (and therefore all of math) if we don’t even know what it is? - Quora

july 2019 by nhaliday

In the realm of mathematics, an object is what it does (I keep quoting Tim Gowers with this phrase, and I will likely do so many more times). The only thing that matters about points, lines, real numbers, sets, functions, groups and tempered distributions is the properties and features and rules they obey. What they “are” is of no concern.

I've seen this idea in a lot of different places

q-n-a
qra
math
lens
abstraction
essence-existence
analytical-holistic
forms-instances
big-picture
aphorism
axioms
definition
characterization
zooming
I've seen this idea in a lot of different places

july 2019 by nhaliday

Rational Sines of Rational Multiples of p

july 2019 by nhaliday

For which rational multiples of p is the sine rational? We have the three trivial cases

[0, pi/2, pi/6]

and we wish to show that these are essentially the only distinct rational sines of rational multiples of p.

The assertion about rational sines of rational multiples of p follows from two fundamental lemmas. The first is

Lemma 1: For any rational number q the value of sin(qp) is a root of a monic polynomial with integer coefficients.

[Pf uses some ideas unfamiliar to me: similarity parameter of Moebius (linear fraction) transformations, and finding a polynomial for a desired root by constructing a Moebius transformation with a finite period.]

...

Lemma 2: Any root of a monic polynomial f(x) with integer coefficients must either be an integer or irrational.

[Gauss's Lemma, cf Dummit-Foote.]

...

nibble
tidbits
org:junk
analysis
trivia
math
algebra
polynomials
fields
characterization
direction
math.CA
math.CV
ground-up
[0, pi/2, pi/6]

and we wish to show that these are essentially the only distinct rational sines of rational multiples of p.

The assertion about rational sines of rational multiples of p follows from two fundamental lemmas. The first is

Lemma 1: For any rational number q the value of sin(qp) is a root of a monic polynomial with integer coefficients.

[Pf uses some ideas unfamiliar to me: similarity parameter of Moebius (linear fraction) transformations, and finding a polynomial for a desired root by constructing a Moebius transformation with a finite period.]

...

Lemma 2: Any root of a monic polynomial f(x) with integer coefficients must either be an integer or irrational.

[Gauss's Lemma, cf Dummit-Foote.]

...

july 2019 by nhaliday

Panel: Systems Programming in 2014 and Beyond | Lang.NEXT 2014 | Channel 9

july 2019 by nhaliday

- Bjarne Stroustrup, Niko Matsakis, Andrei Alexandrescu, Rob Pike

- 2014 so pretty outdated but rare to find a discussion with people like this together

- pretty sure Jonathan Blow asked a couple questions

- Rob Pike compliments Rust at one point. Also kinda softly rags on dynamic typing at one point ("unit testing is what they have instead of static types").

related:

What is Systems Programming, Really?: http://willcrichton.net/notes/systems-programming/

https://news.ycombinator.com/item?id=17948265

https://news.ycombinator.com/item?id=21731878

video
presentation
debate
programming
pls
c(pp)
systems
os
rust
d-lang
golang
computer-memory
legacy
devtools
formal-methods
concurrency
compilers
syntax
parsimony
google
intricacy
thinking
cost-benefit
degrees-of-freedom
facebook
performance
people
rsc
cracker-prog
critique
types
checking
api
flux-stasis
engineering
time
wire-guided
worse-is-better/the-right-thing
static-dynamic
latency-throughput
techtariat
multi
plt
hn
commentary
metal-to-virtual
functional
abstraction
contrarianism
jargon
definition
characterization
reflection
- 2014 so pretty outdated but rare to find a discussion with people like this together

- pretty sure Jonathan Blow asked a couple questions

- Rob Pike compliments Rust at one point. Also kinda softly rags on dynamic typing at one point ("unit testing is what they have instead of static types").

related:

What is Systems Programming, Really?: http://willcrichton.net/notes/systems-programming/

https://news.ycombinator.com/item?id=17948265

https://news.ycombinator.com/item?id=21731878

july 2019 by nhaliday

Less is exponentially more

june 2019 by nhaliday

https://news.ycombinator.com/item?id=16548684

https://news.ycombinator.com/item?id=6417319

https://news.ycombinator.com/item?id=4158865

https://aras-p.info/blog/2018/12/28/Modern-C-Lamentations/

https://thephd.github.io/perspective-standardization-in-2018

https://sean-parent.stlab.cc/2018/12/30/cpp-ruminations.html

http://ericniebler.com/2018/12/05/standard-ranges/

techtariat
rsc
worse-is-better/the-right-thing
blowhards
diogenes
reflection
rhetoric
c(pp)
systems
programming
pls
plt
types
thinking
engineering
nitty-gritty
stories
stock-flow
network-structure
arrows
composition-decomposition
comparison
jvm
golang
degrees-of-freedom
roots
performance
hn
commentary
multi
ideology
intricacy
parsimony
minimalism
tradeoffs
impetus
design
google
python
cracker-prog
aphorism
science
critique
classification
characterization
examples
subculture
culture
grokkability
incentives
interests
latency-throughput
grokkability-clarity
https://news.ycombinator.com/item?id=6417319

https://news.ycombinator.com/item?id=4158865

https://aras-p.info/blog/2018/12/28/Modern-C-Lamentations/

https://thephd.github.io/perspective-standardization-in-2018

https://sean-parent.stlab.cc/2018/12/30/cpp-ruminations.html

http://ericniebler.com/2018/12/05/standard-ranges/

june 2019 by nhaliday

A Taxonomy of Technical Debt | Hacker News

techtariat hn commentary reflection programming engineering nitty-gritty aversion debt analogy cost-benefit time-preference discipline characterization analysis composition-decomposition things classification tech tradeoffs investing long-short-run games thinking metrics spreading metabuch time impact prioritizing models local-global stories examples legacy code-dive system-design big-picture quality project-management

june 2019 by nhaliday

techtariat hn commentary reflection programming engineering nitty-gritty aversion debt analogy cost-benefit time-preference discipline characterization analysis composition-decomposition things classification tech tradeoffs investing long-short-run games thinking metrics spreading metabuch time impact prioritizing models local-global stories examples legacy code-dive system-design big-picture quality project-management

june 2019 by nhaliday

ON THE GEOMETRY OF NASH EQUILIBRIA AND CORRELATED EQUILIBRIA

may 2019 by nhaliday

Abstract: It is well known that the set of correlated equilibrium distributions of an n-player noncooperative game is a convex polytope that includes all the Nash equilibrium distributions. We demonstrate an elementary yet surprising result: the Nash equilibria all lie on the boundary of the polytope.

pdf
nibble
papers
ORFE
game-theory
optimization
geometry
dimensionality
linear-algebra
equilibrium
structure
differential
correlation
iidness
acm
linear-programming
spatial
characterization
levers
may 2019 by nhaliday

Criticism of C++ - Wikipedia

april 2019 by nhaliday

C++ Frequently Questioned Answers: https://yosefk.com/c++fqa/

C++11 FQA anyone?: http://yosefk.com/blog/c11-fqa-anyone.html

What are some of the bad design decisions in the C++ language?: https://www.quora.com/What-are-some-of-the-bad-design-decisions-in-the-C-language

- Brian Bi

wiki
reference
list
debate
critique
programming
pls
c(pp)
systems
compilers
comparison
analysis
memory-management
performance
gotchas
nitty-gritty
yak-shaving
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q-n-a
faq
objektbuch
rant
types
oop
error
philosophy
qra
multi
expert-experience
oly
tradeoffs
homo-hetero
flux-stasis
legacy
syntax
correctness
design
intricacy
impetus
incentives
roots
nonlinearity
degrees-of-freedom
jvm
cost-benefit
characterization
error-handling
C++11 FQA anyone?: http://yosefk.com/blog/c11-fqa-anyone.html

What are some of the bad design decisions in the C++ language?: https://www.quora.com/What-are-some-of-the-bad-design-decisions-in-the-C-language

- Brian Bi

april 2019 by nhaliday

Antinomia Imediata – experiments in a reaction from the left

march 2018 by nhaliday

https://antinomiaimediata.wordpress.com/lrx/

So, what is the Left Reaction? First of all, it’s reaction: opposition to the modern rationalist establishment, the Cathedral. It opposes the universalist Jacobin program of global government, favoring a fractured geopolitics organized through long-evolved complex systems. It’s profoundly anti-socialist and anti-communist, favoring market economy and individualism. It abhors tribalism and seeks a realistic plan for dismantling it (primarily informed by HBD and HBE). It looks at modernity as a degenerative ratchet, whose only way out is intensification (hence clinging to crypto-marxist market-driven acceleration).

How come can any of this still be in the *Left*? It defends equality of power, i.e. freedom. This radical understanding of liberty is deeply rooted in leftist tradition and has been consistently abhored by the Right. LRx is not democrat, is not socialist, is not progressist and is not even liberal (in its current, American use). But it defends equality of power. It’s utopia is individual sovereignty. It’s method is paleo-agorism. The anti-hierarchy of hunter-gatherer nomads is its understanding of the only realistic objective of equality.

...

In more cosmic terms, it seeks only to fulfill the Revolution’s side in the left-right intelligence pump: mutation or creation of paths. Proudhon’s antinomy is essentially about this: the collective force of the socius, evinced in moral standards and social organization vs the creative force of the individuals, that constantly revolutionize and disrupt the social body. The interplay of these forces create reality (it’s a metaphysics indeed): the Absolute (socius) builds so that the (individualistic) Revolution can destroy so that the Absolute may adapt, and then repeat. The good old formula of ‘solve et coagula’.

Ultimately, if the Neoreaction promises eternal hell, the LRx sneers “but Satan is with us”.

https://antinomiaimediata.wordpress.com/2016/12/16/a-statement-of-principles/

Liberty is to be understood as the ability and right of all sentient beings to dispose of their persons and the fruits of their labor, and nothing else, as they see fit. This stems from their self-awareness and their ability to control and choose the content of their actions.

...

Equality is to be understood as the state of no imbalance of power, that is, of no subjection to another sentient being. This stems from their universal ability for empathy, and from their equal ability for reason.

...

It is important to notice that, contrary to usual statements of these two principles, my standpoint is that Liberty and Equality here are not merely compatible, meaning they could coexist in some possible universe, but rather they are two sides of the same coin, complementary and interdependent. There can be NO Liberty where there is no Equality, for the imbalance of power, the state of subjection, will render sentient beings unable to dispose of their persons and the fruits of their labor[1], and it will limit their ability to choose over their rightful jurisdiction. Likewise, there can be NO Equality without Liberty, for restraining sentient beings’ ability to choose and dispose of their persons and fruits of labor will render some more powerful than the rest, and establish a state of subjection.

https://antinomiaimediata.wordpress.com/2017/04/18/flatness/

equality is the founding principle (and ultimately indistinguishable from) freedom. of course, it’s only in one specific sense of “equality” that this sentence is true.

to try and eliminate the bullshit, let’s turn to networks again:

any nodes’ degrees of freedom is the number of nodes they are connected to in a network. freedom is maximum when the network is symmetrically connected, i. e., when all nodes are connected to each other and thus there is no topographical hierarchy (middlemen) – in other words, flatness.

in this understanding, the maximization of freedom is the maximization of entropy production, that is, of intelligence. As Land puts it:

https://antinomiaimediata.wordpress.com/category/philosophy/mutualism/

gnon
blog
stream
politics
polisci
ideology
philosophy
land
accelerationism
left-wing
right-wing
paradox
egalitarianism-hierarchy
civil-liberty
power
hmm
revolution
analytical-holistic
mutation
selection
individualism-collectivism
tribalism
us-them
modernity
multi
tradeoffs
network-structure
complex-systems
cybernetics
randy-ayndy
insight
contrarianism
metameta
metabuch
characterization
cooperate-defect
n-factor
altruism
list
coordination
graphs
visual-understanding
cartoons
intelligence
entropy-like
thermo
information-theory
order-disorder
decentralized
distribution
degrees-of-freedom
analogy
graph-theory
extrema
evolution
interdisciplinary
bio
differential
geometry
anglosphere
optimate
nascent-state
deep-materialism
new-religion
cool
mystic
the-classics
self-interest
interests
reason
volo-avolo
flux-stasis
invariance
government
markets
paying-rent
cost-benefit
peace-violence
frontier
exit-voice
nl-and-so-can-you
war
track-record
usa
history
mostly-modern
world-war
military
justice
protestant-cathol
So, what is the Left Reaction? First of all, it’s reaction: opposition to the modern rationalist establishment, the Cathedral. It opposes the universalist Jacobin program of global government, favoring a fractured geopolitics organized through long-evolved complex systems. It’s profoundly anti-socialist and anti-communist, favoring market economy and individualism. It abhors tribalism and seeks a realistic plan for dismantling it (primarily informed by HBD and HBE). It looks at modernity as a degenerative ratchet, whose only way out is intensification (hence clinging to crypto-marxist market-driven acceleration).

How come can any of this still be in the *Left*? It defends equality of power, i.e. freedom. This radical understanding of liberty is deeply rooted in leftist tradition and has been consistently abhored by the Right. LRx is not democrat, is not socialist, is not progressist and is not even liberal (in its current, American use). But it defends equality of power. It’s utopia is individual sovereignty. It’s method is paleo-agorism. The anti-hierarchy of hunter-gatherer nomads is its understanding of the only realistic objective of equality.

...

In more cosmic terms, it seeks only to fulfill the Revolution’s side in the left-right intelligence pump: mutation or creation of paths. Proudhon’s antinomy is essentially about this: the collective force of the socius, evinced in moral standards and social organization vs the creative force of the individuals, that constantly revolutionize and disrupt the social body. The interplay of these forces create reality (it’s a metaphysics indeed): the Absolute (socius) builds so that the (individualistic) Revolution can destroy so that the Absolute may adapt, and then repeat. The good old formula of ‘solve et coagula’.

Ultimately, if the Neoreaction promises eternal hell, the LRx sneers “but Satan is with us”.

https://antinomiaimediata.wordpress.com/2016/12/16/a-statement-of-principles/

Liberty is to be understood as the ability and right of all sentient beings to dispose of their persons and the fruits of their labor, and nothing else, as they see fit. This stems from their self-awareness and their ability to control and choose the content of their actions.

...

Equality is to be understood as the state of no imbalance of power, that is, of no subjection to another sentient being. This stems from their universal ability for empathy, and from their equal ability for reason.

...

It is important to notice that, contrary to usual statements of these two principles, my standpoint is that Liberty and Equality here are not merely compatible, meaning they could coexist in some possible universe, but rather they are two sides of the same coin, complementary and interdependent. There can be NO Liberty where there is no Equality, for the imbalance of power, the state of subjection, will render sentient beings unable to dispose of their persons and the fruits of their labor[1], and it will limit their ability to choose over their rightful jurisdiction. Likewise, there can be NO Equality without Liberty, for restraining sentient beings’ ability to choose and dispose of their persons and fruits of labor will render some more powerful than the rest, and establish a state of subjection.

https://antinomiaimediata.wordpress.com/2017/04/18/flatness/

equality is the founding principle (and ultimately indistinguishable from) freedom. of course, it’s only in one specific sense of “equality” that this sentence is true.

to try and eliminate the bullshit, let’s turn to networks again:

any nodes’ degrees of freedom is the number of nodes they are connected to in a network. freedom is maximum when the network is symmetrically connected, i. e., when all nodes are connected to each other and thus there is no topographical hierarchy (middlemen) – in other words, flatness.

in this understanding, the maximization of freedom is the maximization of entropy production, that is, of intelligence. As Land puts it:

https://antinomiaimediata.wordpress.com/category/philosophy/mutualism/

march 2018 by nhaliday

Prisoner's dilemma - Wikipedia

march 2018 by nhaliday

caveat to result below:

An extension of the IPD is an evolutionary stochastic IPD, in which the relative abundance of particular strategies is allowed to change, with more successful strategies relatively increasing. This process may be accomplished by having less successful players imitate the more successful strategies, or by eliminating less successful players from the game, while multiplying the more successful ones. It has been shown that unfair ZD strategies are not evolutionarily stable. The key intuition is that an evolutionarily stable strategy must not only be able to invade another population (which extortionary ZD strategies can do) but must also perform well against other players of the same type (which extortionary ZD players do poorly, because they reduce each other's surplus).[14]

Theory and simulations confirm that beyond a critical population size, ZD extortion loses out in evolutionary competition against more cooperative strategies, and as a result, the average payoff in the population increases when the population is bigger. In addition, there are some cases in which extortioners may even catalyze cooperation by helping to break out of a face-off between uniform defectors and win–stay, lose–switch agents.[8]

https://alfanl.com/2018/04/12/defection/

Nature boils down to a few simple concepts.

Haters will point out that I oversimplify. The haters are wrong. I am good at saying a lot with few words. Nature indeed boils down to a few simple concepts.

In life, you can either cooperate or defect.

Used to be that defection was the dominant strategy, say in the time when the Roman empire started to crumble. Everybody complained about everybody and in the end nothing got done. Then came Jesus, who told people to be loving and cooperative, and boom: 1800 years later we get the industrial revolution.

Because of Jesus we now find ourselves in a situation where cooperation is the dominant strategy. A normie engages in a ton of cooperation: with the tax collector who wants more and more of his money, with schools who want more and more of his kid’s time, with media who wants him to repeat more and more party lines, with the Zeitgeist of the Collective Spirit of the People’s Progress Towards a New Utopia. Essentially, our normie is cooperating himself into a crumbling Western empire.

Turns out that if everyone blindly cooperates, parasites sprout up like weeds until defection once again becomes the standard.

The point of a post-Christian religion is to once again create conditions for the kind of cooperation that led to the industrial revolution. This necessitates throwing out undead Christianity: you do not blindly cooperate. You cooperate with people that cooperate with you, you defect on people that defect on you. Christianity mixed with Darwinism. God and Gnon meet.

This also means we re-establish spiritual hierarchy, which, like regular hierarchy, is a prerequisite for cooperation. It is this hierarchical cooperation that turns a household into a force to be reckoned with, that allows a group of men to unite as a front against their enemies, that allows a tribe to conquer the world. Remember: Scientology bullied the Cathedral’s tax department into submission.

With a functioning hierarchy, men still gossip, lie and scheme, but they will do so in whispers behind closed doors. In your face they cooperate and contribute to the group’s wellbeing because incentives are thus that contributing to group wellbeing heightens status.

Without a functioning hierarchy, men gossip, lie and scheme, but they do so in your face, and they tell you that you are positively deluded for accusing them of gossiping, lying and scheming. Seeds will not sprout in such ground.

Spiritual dominance is established in the same way any sort of dominance is established: fought for, taken. But the fight is ritualistic. You can’t force spiritual dominance if no one listens, or if you are silenced the ritual is not allowed to happen.

If one of our priests is forbidden from establishing spiritual dominance, that is a sure sign an enemy priest is in better control and has vested interest in preventing you from establishing spiritual dominance..

They defect on you, you defect on them. Let them suffer the consequences of enemy priesthood, among others characterized by the annoying tendency that very little is said with very many words.

https://contingentnotarbitrary.com/2018/04/14/rederiving-christianity/

To recap, we started with a secular definition of Logos and noted that its telos is existence. Given human nature, game theory and the power of cooperation, the highest expression of that telos is freely chosen universal love, tempered by constant vigilance against defection while maintaining compassion for the defectors and forgiving those who repent. In addition, we must know the telos in order to fulfill it.

In Christian terms, looks like we got over half of the Ten Commandments (know Logos for the First, don’t defect or tempt yourself to defect for the rest), the importance of free will, the indestructibility of evil (group cooperation vs individual defection), loving the sinner and hating the sin (with defection as the sin), forgiveness (with conditions), and love and compassion toward all, assuming only secular knowledge and that it’s good to exist.

Iterated Prisoner's Dilemma is an Ultimatum Game: http://infoproc.blogspot.com/2012/07/iterated-prisoners-dilemma-is-ultimatum.html

The history of IPD shows that bounded cognition prevented the dominant strategies from being discovered for over over 60 years, despite significant attention from game theorists, computer scientists, economists, evolutionary biologists, etc. Press and Dyson have shown that IPD is effectively an ultimatum game, which is very different from the Tit for Tat stories told by generations of people who worked on IPD (Axelrod, Dawkins, etc., etc.).

...

For evolutionary biologists: Dyson clearly thinks this result has implications for multilevel (group vs individual selection):

... Cooperation loses and defection wins. The ZD strategies confirm this conclusion and make it sharper. ... The system evolved to give cooperative tribes an advantage over non-cooperative tribes, using punishment to give cooperation an evolutionary advantage within the tribe. This double selection of tribes and individuals goes way beyond the Prisoners' Dilemma model.

implications for fractionalized Europe vis-a-vis unified China?

and more broadly does this just imply we're doomed in the long run RE: cooperation, morality, the "good society", so on...? war and group-selection is the only way to get a non-crab bucket civilization?

Iterated Prisoner’s Dilemma contains strategies that dominate any evolutionary opponent:

http://www.pnas.org/content/109/26/10409.full

http://www.pnas.org/content/109/26/10409.full.pdf

https://www.edge.org/conversation/william_h_press-freeman_dyson-on-iterated-prisoners-dilemma-contains-strategies-that

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

analogy for ultimatum game: the state gives the demos a bargain take-it-or-leave-it, and...if the demos refuses...violence?

The nature of human altruism: http://sci-hub.tw/https://www.nature.com/articles/nature02043

- Ernst Fehr & Urs Fischbacher

Some of the most fundamental questions concerning our evolutionary origins, our social relations, and the organization of society are centred around issues of altruism and selfishness. Experimental evidence indicates that human altruism is a powerful force and is unique in the animal world. However, there is much individual heterogeneity and the interaction between altruists and selfish individuals is vital to human cooperation. Depending on the environment, a minority of altruists can force a majority of selfish individuals to cooperate or, conversely, a few egoists can induce a large number of altruists to defect. Current gene-based evolutionary theories cannot explain important patterns of human altruism, pointing towards the importance of both theories of cultural evolution as well as gene–culture co-evolution.

...

Why are humans so unusual among animals in this respect? We propose that quantitatively, and probably even qualitatively, unique patterns of human altruism provide the answer to this question. Human altruism goes far beyond that which has been observed in the animal world. Among animals, fitness-reducing acts that confer fitness benefits on other individuals are largely restricted to kin groups; despite several decades of research, evidence for reciprocal altruism in pair-wise repeated encounters4,5 remains scarce6–8. Likewise, there is little evidence so far that individual reputation building affects cooperation in animals, which contrasts strongly with what we find in humans. If we randomly pick two human strangers from a modern society and give them the chance to engage in repeated anonymous exchanges in a laboratory experiment, there is a high probability that reciprocally altruistic behaviour will emerge spontaneously9,10.

However, human altruism extends far beyond reciprocal altruism and reputation-based cooperation, taking the form of strong reciprocity11,12. Strong reciprocity is a combination of altruistic rewarding, which is a predisposition to reward others for cooperative, norm-abiding behaviours, and altruistic punishment, which is a propensity to impose sanctions on others for norm violations. Strong reciprocators bear the cost of rewarding or punishing even if they gain no individual economic benefit whatsoever from their acts. In contrast, reciprocal altruists, as they have been defined in the biological literature4,5, reward and punish only if this is in their long-term self-interest. Strong reciprocity thus constitutes a powerful incentive for cooperation even in non-repeated interactions and when reputation gains are absent, because strong reciprocators will reward those who cooperate and punish those who defect.

...

We will show that the interaction between selfish and strongly reciprocal … [more]

concept
conceptual-vocab
wiki
reference
article
models
GT-101
game-theory
anthropology
cultural-dynamics
trust
cooperate-defect
coordination
iteration-recursion
sequential
axelrod
discrete
smoothness
evolution
evopsych
EGT
economics
behavioral-econ
sociology
new-religion
deep-materialism
volo-avolo
characterization
hsu
scitariat
altruism
justice
group-selection
decision-making
tribalism
organizing
hari-seldon
theory-practice
applicability-prereqs
bio
finiteness
multi
history
science
social-science
decision-theory
commentary
study
summary
giants
the-trenches
zero-positive-sum
🔬
bounded-cognition
info-dynamics
org:edge
explanation
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An extension of the IPD is an evolutionary stochastic IPD, in which the relative abundance of particular strategies is allowed to change, with more successful strategies relatively increasing. This process may be accomplished by having less successful players imitate the more successful strategies, or by eliminating less successful players from the game, while multiplying the more successful ones. It has been shown that unfair ZD strategies are not evolutionarily stable. The key intuition is that an evolutionarily stable strategy must not only be able to invade another population (which extortionary ZD strategies can do) but must also perform well against other players of the same type (which extortionary ZD players do poorly, because they reduce each other's surplus).[14]

Theory and simulations confirm that beyond a critical population size, ZD extortion loses out in evolutionary competition against more cooperative strategies, and as a result, the average payoff in the population increases when the population is bigger. In addition, there are some cases in which extortioners may even catalyze cooperation by helping to break out of a face-off between uniform defectors and win–stay, lose–switch agents.[8]

https://alfanl.com/2018/04/12/defection/

Nature boils down to a few simple concepts.

Haters will point out that I oversimplify. The haters are wrong. I am good at saying a lot with few words. Nature indeed boils down to a few simple concepts.

In life, you can either cooperate or defect.

Used to be that defection was the dominant strategy, say in the time when the Roman empire started to crumble. Everybody complained about everybody and in the end nothing got done. Then came Jesus, who told people to be loving and cooperative, and boom: 1800 years later we get the industrial revolution.

Because of Jesus we now find ourselves in a situation where cooperation is the dominant strategy. A normie engages in a ton of cooperation: with the tax collector who wants more and more of his money, with schools who want more and more of his kid’s time, with media who wants him to repeat more and more party lines, with the Zeitgeist of the Collective Spirit of the People’s Progress Towards a New Utopia. Essentially, our normie is cooperating himself into a crumbling Western empire.

Turns out that if everyone blindly cooperates, parasites sprout up like weeds until defection once again becomes the standard.

The point of a post-Christian religion is to once again create conditions for the kind of cooperation that led to the industrial revolution. This necessitates throwing out undead Christianity: you do not blindly cooperate. You cooperate with people that cooperate with you, you defect on people that defect on you. Christianity mixed with Darwinism. God and Gnon meet.

This also means we re-establish spiritual hierarchy, which, like regular hierarchy, is a prerequisite for cooperation. It is this hierarchical cooperation that turns a household into a force to be reckoned with, that allows a group of men to unite as a front against their enemies, that allows a tribe to conquer the world. Remember: Scientology bullied the Cathedral’s tax department into submission.

With a functioning hierarchy, men still gossip, lie and scheme, but they will do so in whispers behind closed doors. In your face they cooperate and contribute to the group’s wellbeing because incentives are thus that contributing to group wellbeing heightens status.

Without a functioning hierarchy, men gossip, lie and scheme, but they do so in your face, and they tell you that you are positively deluded for accusing them of gossiping, lying and scheming. Seeds will not sprout in such ground.

Spiritual dominance is established in the same way any sort of dominance is established: fought for, taken. But the fight is ritualistic. You can’t force spiritual dominance if no one listens, or if you are silenced the ritual is not allowed to happen.

If one of our priests is forbidden from establishing spiritual dominance, that is a sure sign an enemy priest is in better control and has vested interest in preventing you from establishing spiritual dominance..

They defect on you, you defect on them. Let them suffer the consequences of enemy priesthood, among others characterized by the annoying tendency that very little is said with very many words.

https://contingentnotarbitrary.com/2018/04/14/rederiving-christianity/

To recap, we started with a secular definition of Logos and noted that its telos is existence. Given human nature, game theory and the power of cooperation, the highest expression of that telos is freely chosen universal love, tempered by constant vigilance against defection while maintaining compassion for the defectors and forgiving those who repent. In addition, we must know the telos in order to fulfill it.

In Christian terms, looks like we got over half of the Ten Commandments (know Logos for the First, don’t defect or tempt yourself to defect for the rest), the importance of free will, the indestructibility of evil (group cooperation vs individual defection), loving the sinner and hating the sin (with defection as the sin), forgiveness (with conditions), and love and compassion toward all, assuming only secular knowledge and that it’s good to exist.

Iterated Prisoner's Dilemma is an Ultimatum Game: http://infoproc.blogspot.com/2012/07/iterated-prisoners-dilemma-is-ultimatum.html

The history of IPD shows that bounded cognition prevented the dominant strategies from being discovered for over over 60 years, despite significant attention from game theorists, computer scientists, economists, evolutionary biologists, etc. Press and Dyson have shown that IPD is effectively an ultimatum game, which is very different from the Tit for Tat stories told by generations of people who worked on IPD (Axelrod, Dawkins, etc., etc.).

...

For evolutionary biologists: Dyson clearly thinks this result has implications for multilevel (group vs individual selection):

... Cooperation loses and defection wins. The ZD strategies confirm this conclusion and make it sharper. ... The system evolved to give cooperative tribes an advantage over non-cooperative tribes, using punishment to give cooperation an evolutionary advantage within the tribe. This double selection of tribes and individuals goes way beyond the Prisoners' Dilemma model.

implications for fractionalized Europe vis-a-vis unified China?

and more broadly does this just imply we're doomed in the long run RE: cooperation, morality, the "good society", so on...? war and group-selection is the only way to get a non-crab bucket civilization?

Iterated Prisoner’s Dilemma contains strategies that dominate any evolutionary opponent:

http://www.pnas.org/content/109/26/10409.full

http://www.pnas.org/content/109/26/10409.full.pdf

https://www.edge.org/conversation/william_h_press-freeman_dyson-on-iterated-prisoners-dilemma-contains-strategies-that

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

analogy for ultimatum game: the state gives the demos a bargain take-it-or-leave-it, and...if the demos refuses...violence?

The nature of human altruism: http://sci-hub.tw/https://www.nature.com/articles/nature02043

- Ernst Fehr & Urs Fischbacher

Some of the most fundamental questions concerning our evolutionary origins, our social relations, and the organization of society are centred around issues of altruism and selfishness. Experimental evidence indicates that human altruism is a powerful force and is unique in the animal world. However, there is much individual heterogeneity and the interaction between altruists and selfish individuals is vital to human cooperation. Depending on the environment, a minority of altruists can force a majority of selfish individuals to cooperate or, conversely, a few egoists can induce a large number of altruists to defect. Current gene-based evolutionary theories cannot explain important patterns of human altruism, pointing towards the importance of both theories of cultural evolution as well as gene–culture co-evolution.

...

Why are humans so unusual among animals in this respect? We propose that quantitatively, and probably even qualitatively, unique patterns of human altruism provide the answer to this question. Human altruism goes far beyond that which has been observed in the animal world. Among animals, fitness-reducing acts that confer fitness benefits on other individuals are largely restricted to kin groups; despite several decades of research, evidence for reciprocal altruism in pair-wise repeated encounters4,5 remains scarce6–8. Likewise, there is little evidence so far that individual reputation building affects cooperation in animals, which contrasts strongly with what we find in humans. If we randomly pick two human strangers from a modern society and give them the chance to engage in repeated anonymous exchanges in a laboratory experiment, there is a high probability that reciprocally altruistic behaviour will emerge spontaneously9,10.

However, human altruism extends far beyond reciprocal altruism and reputation-based cooperation, taking the form of strong reciprocity11,12. Strong reciprocity is a combination of altruistic rewarding, which is a predisposition to reward others for cooperative, norm-abiding behaviours, and altruistic punishment, which is a propensity to impose sanctions on others for norm violations. Strong reciprocators bear the cost of rewarding or punishing even if they gain no individual economic benefit whatsoever from their acts. In contrast, reciprocal altruists, as they have been defined in the biological literature4,5, reward and punish only if this is in their long-term self-interest. Strong reciprocity thus constitutes a powerful incentive for cooperation even in non-repeated interactions and when reputation gains are absent, because strong reciprocators will reward those who cooperate and punish those who defect.

...

We will show that the interaction between selfish and strongly reciprocal … [more]

march 2018 by nhaliday

Hyperbolic angle - Wikipedia

november 2017 by nhaliday

A unit circle {\displaystyle x^{2}+y^{2}=1} x^2 + y^2 = 1 has a circular sector with an area half of the circular angle in radians. Analogously, a unit hyperbola {\displaystyle x^{2}-y^{2}=1} {\displaystyle x^{2}-y^{2}=1} has a hyperbolic sector with an area half of the hyperbolic angle.

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november 2017 by nhaliday

[1703.10548] A multiplicative process for generating a beta-like survival function with application to the UK 2016 EU referendum results

study papers preprint physics social-science sociology interdisciplinary structure network-structure distribution models eric-kaufmann britain brexit elections plots nonlinearity probability stochastic-processes data-science acm characterization atoms concept power-law polisci org:mat

october 2017 by nhaliday

study papers preprint physics social-science sociology interdisciplinary structure network-structure distribution models eric-kaufmann britain brexit elections plots nonlinearity probability stochastic-processes data-science acm characterization atoms concept power-law polisci org:mat

october 2017 by nhaliday

multivariate analysis - Is it possible to have a pair of Gaussian random variables for which the joint distribution is not Gaussian? - Cross Validated

october 2017 by nhaliday

The bivariate normal distribution is the exception, not the rule!

It is important to recognize that "almost all" joint distributions with normal marginals are not the bivariate normal distribution. That is, the common viewpoint that joint distributions with normal marginals that are not the bivariate normal are somehow "pathological", is a bit misguided.

Certainly, the multivariate normal is extremely important due to its stability under linear transformations, and so receives the bulk of attention in applications.

note: there is a multivariate central limit theorem, so those such applications have no problem

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It is important to recognize that "almost all" joint distributions with normal marginals are not the bivariate normal distribution. That is, the common viewpoint that joint distributions with normal marginals that are not the bivariate normal are somehow "pathological", is a bit misguided.

Certainly, the multivariate normal is extremely important due to its stability under linear transformations, and so receives the bulk of attention in applications.

note: there is a multivariate central limit theorem, so those such applications have no problem

october 2017 by nhaliday

New Theory Cracks Open the Black Box of Deep Learning | Quanta Magazine

september 2017 by nhaliday

A new idea called the “information bottleneck” is helping to explain the puzzling success of today’s artificial-intelligence algorithms — and might also explain how human brains learn.

sounds like he's just talking about autoencoders?

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sounds like he's just talking about autoencoders?

september 2017 by nhaliday

co.combinatorics - Classification of Platonic solids - MathOverflow

july 2017 by nhaliday

My question is very basic: where can I find a complete (and hopefully self-contained) proof of the classification of Platonic solids? In all the references that I found, they use Euler's formula v−e+f=2v−e+f=2 to show that there are exactly five possible triples (v,e,f)(v,e,f). But of course this is not a complete proof because it does not rule out the possibility of different configurations or deformations. Has anyone ever written up a complete proof of this statement?!

...

This is a classical question. Here is my reading of it: Why is there a unique polytope with given combinatorics of faces, which are all regular polygons? Of course, for simple polytopes (tetrahedron, cube, dodecahedron) this is clear, but for the octahedron and icosahedron this is less clear.

The answer lies in the Cauchy's theorem. It was Legendre, while writing his Elements of Geometry and Trigonometry, noticed that Euclid's proof is incomplete in the Elements. Curiously, Euclid finds both radii of inscribed and circumscribed spheres (correctly) without ever explaining why they exist. Cauchy worked out a proof while still a student in 1813, more or less specifically for this purpose. The proof also had a technical gap which was found and patched up by Steinitz in 1920s.

The complete (corrected) proof can be found in the celebrated Proofs from the Book, or in Marcel Berger's Geometry. My book gives a bit more of historical context and some soft arguments (ch. 19). It's worth comparing this proof with (an erroneous) pre-Steinitz exposition, say in Hadamard's Leçons de Géométrie Elémentaire II, or with an early post-Steinitz correct but tedious proof given in (otherwise, excellent) Alexandrov's monograph (see also ch.26 in my book which compares all the approaches).

P.S. Note that Coxeter in Regular Polytopes can completely avoid this issue but taking a different (modern) definition of the regular polytopes (which are symmetric under group actions). For a modern exposition and the state of art of this approach, see McMullen and Schulte's Abstract Regular Polytopes.

https://en.wikipedia.org/wiki/Platonic_solid#Classification

https://mathoverflow.net/questions/46502/on-the-number-of-archimedean-solids

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This is a classical question. Here is my reading of it: Why is there a unique polytope with given combinatorics of faces, which are all regular polygons? Of course, for simple polytopes (tetrahedron, cube, dodecahedron) this is clear, but for the octahedron and icosahedron this is less clear.

The answer lies in the Cauchy's theorem. It was Legendre, while writing his Elements of Geometry and Trigonometry, noticed that Euclid's proof is incomplete in the Elements. Curiously, Euclid finds both radii of inscribed and circumscribed spheres (correctly) without ever explaining why they exist. Cauchy worked out a proof while still a student in 1813, more or less specifically for this purpose. The proof also had a technical gap which was found and patched up by Steinitz in 1920s.

The complete (corrected) proof can be found in the celebrated Proofs from the Book, or in Marcel Berger's Geometry. My book gives a bit more of historical context and some soft arguments (ch. 19). It's worth comparing this proof with (an erroneous) pre-Steinitz exposition, say in Hadamard's Leçons de Géométrie Elémentaire II, or with an early post-Steinitz correct but tedious proof given in (otherwise, excellent) Alexandrov's monograph (see also ch.26 in my book which compares all the approaches).

P.S. Note that Coxeter in Regular Polytopes can completely avoid this issue but taking a different (modern) definition of the regular polytopes (which are symmetric under group actions). For a modern exposition and the state of art of this approach, see McMullen and Schulte's Abstract Regular Polytopes.

https://en.wikipedia.org/wiki/Platonic_solid#Classification

https://mathoverflow.net/questions/46502/on-the-number-of-archimedean-solids

july 2017 by nhaliday

On the Cobb–Douglas Production Function

june 2017 by nhaliday

- Kim Border

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june 2017 by nhaliday

Von Neumann–Morgenstern utility theorem - Wikipedia

economics micro game-theory values models existence uniqueness characterization wiki reference nibble proofs ORFE expectancy formal-values decision-making decision-theory acm definition outcome-risk linearity von-neumann giants

april 2017 by nhaliday

economics micro game-theory values models existence uniqueness characterization wiki reference nibble proofs ORFE expectancy formal-values decision-making decision-theory acm definition outcome-risk linearity von-neumann giants

april 2017 by nhaliday

18.177 Theory of Probability: Fall, 2015

february 2017 by nhaliday

https://ocw.mit.edu/courses/mathematics/18-177-universal-random-structures-in-2d-fall-2015/index.htm

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february 2017 by nhaliday

vector spaces - Difference between metric and norm made concrete: The case of Euclid - Mathematics Stack Exchange

february 2017 by nhaliday

for vector space metric V, translation invariance+homogeneity implies d(x, 0) is norm on x in V

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february 2017 by nhaliday

More on Multivariate Gaussians

february 2017 by nhaliday

Fact #1: mean and covariance uniquely determine distribution

Fact #3: closure under sum, marginalizing, and conditioning

covariance of conditional distribution is given by a Schur complement (independent of x_B. is that obvious?)

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Fact #3: closure under sum, marginalizing, and conditioning

covariance of conditional distribution is given by a Schur complement (independent of x_B. is that obvious?)

february 2017 by nhaliday

Equivalence between counting and sampling

february 2017 by nhaliday

also: every counting problem either has FPTRAS or no approx. w/i polynomial factor

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february 2017 by nhaliday

Structure theorem for finitely generated modules over a principal ideal domain - Wikipedia

february 2017 by nhaliday

- finitely generative modules over PID isomorphic to sum of quotients by decreasing sequences of proper ideals

- never really understood the proof of this in Ma5b

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- never really understood the proof of this in Ma5b

february 2017 by nhaliday

Relationships among probability distributions - Wikipedia

february 2017 by nhaliday

- One distribution is a special case of another with a broader parameter space

- Transforms (function of a random variable);

- Combinations (function of several variables);

- Approximation (limit) relationships;

- Compound relationships (useful for Bayesian inference);

- Duality;

- Conjugate priors.

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list
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- Transforms (function of a random variable);

- Combinations (function of several variables);

- Approximation (limit) relationships;

- Compound relationships (useful for Bayesian inference);

- Duality;

- Conjugate priors.

february 2017 by nhaliday

linear algebra - What's an intuitive way to think about the determinant? - Mathematics Stack Exchange

january 2017 by nhaliday

goes through the standard volume of parallelepiped/multilinear alternating map formulations

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january 2017 by nhaliday

Dvoretzky's theorem - Wikipedia

january 2017 by nhaliday

In mathematics, Dvoretzky's theorem is an important structural theorem about normed vector spaces proved by Aryeh Dvoretzky in the early 1960s, answering a question of Alexander Grothendieck. In essence, it says that every sufficiently high-dimensional normed vector space will have low-dimensional subspaces that are approximately Euclidean. Equivalently, every high-dimensional bounded symmetric convex set has low-dimensional sections that are approximately ellipsoids.

http://mathoverflow.net/questions/143527/intuitive-explanation-of-dvoretzkys-theorem

http://mathoverflow.net/questions/46278/unexpected-applications-of-dvoretzkys-theorem

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http://mathoverflow.net/questions/143527/intuitive-explanation-of-dvoretzkys-theorem

http://mathoverflow.net/questions/46278/unexpected-applications-of-dvoretzkys-theorem

january 2017 by nhaliday

Existence of the moment generating function and variance - Cross Validated

january 2017 by nhaliday

This question provides a nice opportunity to collect some facts on moment-generating functions (mgf).

In the answer below, we do the following:

1. Show that if the mgf is finite for at least one (strictly) positive value and one negative value, then all positive moments of X are finite (including nonintegral moments).

2. Prove that the condition in the first item above is equivalent to the distribution of X having exponentially bounded tails. In other words, the tails of X fall off at least as fast as those of an exponential random variable Z (up to a constant).

3. Provide a quick note on the characterization of the distribution by its mgf provided it satisfies the condition in item 1.

4. Explore some examples and counterexamples to aid our intuition and, particularly, to show that we should not read undue importance into the lack of finiteness of the mgf.

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In the answer below, we do the following:

1. Show that if the mgf is finite for at least one (strictly) positive value and one negative value, then all positive moments of X are finite (including nonintegral moments).

2. Prove that the condition in the first item above is equivalent to the distribution of X having exponentially bounded tails. In other words, the tails of X fall off at least as fast as those of an exponential random variable Z (up to a constant).

3. Provide a quick note on the characterization of the distribution by its mgf provided it satisfies the condition in item 1.

4. Explore some examples and counterexamples to aid our intuition and, particularly, to show that we should not read undue importance into the lack of finiteness of the mgf.

january 2017 by nhaliday

pr.probability - When are probability distributions completely determined by their moments? - MathOverflow

january 2017 by nhaliday

Roughly speaking, if the sequence of moments doesn't grow too quickly, then the distribution is determined by its moments. One sufficient condition is that if the moment generating function of a random variable has positive radius of convergence, then that random variable is determined by its moments.

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january 2017 by nhaliday

st.statistics - Why is it so cool to square numbers (in terms of finding the standard deviation)? - MathOverflow

q-n-a overflow math stats concept motivation curiosity oly mathtariat probability soft-question acm moments nibble definition limits concentration-of-measure s:* characterization

january 2017 by nhaliday

q-n-a overflow math stats concept motivation curiosity oly mathtariat probability soft-question acm moments nibble definition limits concentration-of-measure s:* characterization

january 2017 by nhaliday

ds.algorithms - How does the Multiplicative Weights Update method maximize entropy? - Theoretical Computer Science Stack Exchange

q-n-a overflow tcs acm algorithms optimization online-learning yoga characterization ground-up explanation proofs entropy-like nibble identity properties amortization-potential

january 2017 by nhaliday

q-n-a overflow tcs acm algorithms optimization online-learning yoga characterization ground-up explanation proofs entropy-like nibble identity properties amortization-potential

january 2017 by nhaliday

Notes on concurrency bugs

dan-luu tech programming concurrency debugging data engineering techtariat intricacy structure characterization composition-decomposition distribution empirical correctness tools devtools formal-methods state meta-analysis analysis objektbuch volo-avolo degrees-of-freedom

january 2017 by nhaliday

dan-luu tech programming concurrency debugging data engineering techtariat intricacy structure characterization composition-decomposition distribution empirical correctness tools devtools formal-methods state meta-analysis analysis objektbuch volo-avolo degrees-of-freedom

january 2017 by nhaliday

definition - Why square the difference instead of taking the absolute value in standard deviation? - Cross Validated

stats acm motivation synthesis q-n-a discussion probability tidbits overflow soft-question bias-variance curiosity moments robust comparison nibble s:* characterization limits concentration-of-measure

december 2016 by nhaliday

stats acm motivation synthesis q-n-a discussion probability tidbits overflow soft-question bias-variance curiosity moments robust comparison nibble s:* characterization limits concentration-of-measure

december 2016 by nhaliday

Quarter-Turns | The n-Category Café

december 2016 by nhaliday

In other words, call an operator T a quarter-turn if ⟨Tx,x⟩=0 for all x. Then the real quarter-turns correspond to the skew symmetric matrices — but apart from the zero operator, there are no complex quarter turns at all.

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december 2016 by nhaliday

ISOMETRIES OF R^n

november 2016 by nhaliday

all Euclidean isometries are affine

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november 2016 by nhaliday

A proof of the Mazur-Ulam theorem

november 2016 by nhaliday

all surjective isometries are affine

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november 2016 by nhaliday

Overcoming Bias : Play Will Persist

ritual hanson prediction speculation ems futurism society contrarianism play optimism ratty malthus farmers-and-foragers within-without impetus telos-atelos illusion psychology social-psych anthropology cost-benefit values flux-stasis formal-values moloch status trust coordination duty competition signaling evolution model-organism nature characterization applicability-prereqs

october 2016 by nhaliday

ritual hanson prediction speculation ems futurism society contrarianism play optimism ratty malthus farmers-and-foragers within-without impetus telos-atelos illusion psychology social-psych anthropology cost-benefit values flux-stasis formal-values moloch status trust coordination duty competition signaling evolution model-organism nature characterization applicability-prereqs

october 2016 by nhaliday

examples - can another topology be given to $mathbb R$ so it has the same continuous maps $mathbb Rrightarrow mathbb R$? - MathOverflow

august 2016 by nhaliday

only such topology is Euclidean

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august 2016 by nhaliday

ho.history overview - Does any research mathematics involve solving functional equations? - MathOverflow

math reflection expert characterization tidbits q-n-a overflow oly mathtariat gowers motivation nibble expert-experience rec-math heavyweights explanation roots explanans properties

july 2016 by nhaliday

math reflection expert characterization tidbits q-n-a overflow oly mathtariat gowers motivation nibble expert-experience rec-math heavyweights explanation roots explanans properties

july 2016 by nhaliday

Kullback–Leibler divergence - Wikipedia, the free encyclopedia

may 2016 by nhaliday

see https://en.wikipedia.org/wiki/Kullback%E2%80%93Leibler_divergence#Motivation especially

https://twitter.com/SimonDeDeo/status/993881889143447552

https://archive.is/hZcVb

Kullback-Leibler divergence has an enormous number of interpretations and uses: psychological, epistemic, thermodynamic, statistical, computational, geometrical... I am pretty sure I could teach an entire graduate seminar on it.

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https://twitter.com/SimonDeDeo/status/993881889143447552

https://archive.is/hZcVb

Kullback-Leibler divergence has an enormous number of interpretations and uses: psychological, epistemic, thermodynamic, statistical, computational, geometrical... I am pretty sure I could teach an entire graduate seminar on it.

may 2016 by nhaliday

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