61
Using spaced repetition systems to see through a piece of mathematics
By Michael Nielsen, January 2019
Most cited
Posts that commenters keep linking to, ranked by how many different people have cited them in Hacker News comments. 494 posts.
62
Analysis of bank PIN numbers
Is your PIN number too predictable? Detailed analysis on PIN number databases.
63
Quantum Computing for the Curious
Presented in an experimental mnemonic medium that makes it almost effortless to remember what you read
64
Warning Signs in Experimental Design and Interpretation (2007)
When an experimental study states "The group with treatment X had significantly less disease ( p = 1%)", many people interpret this statement as being equivalent to "there is a 99% chance that if I do treatment X it will prevent disease." This essay explains why these statements are not equivalent. For such an…
65
Regular Expression Matching: the Virtual Machine Approach
Name the most widely used bytecode interpreter or virtual machine. Sun's JVM? Adobe's Flash? .NET and Mono? Perl? Python? PHP? These are all certainly popular, but there's one more widely used than all those combined. That bytecode interpreter is Henry Spencer's regular expression library and its many descendants.
66
Finite state machines as data structure for representing ordered sets and maps
It turns out that finite state machines are useful for things other than expressing computation. Finite state machines can also be used to compactly represent ordered sets or maps of strings that can be searched very quickly.
67
Mona Lisa in 50 polygons, using a genetic algorithm (2008)
This weekend I decided to play around a bit with genetic programming and put evolution to the test, the test of fine art 🙂
68
Data Compression Explained (2012)
Copyright (C) 2010-2012, Dell, Inc . You are permitted to copy and distribute material from this book provided (1) any material you distribute includes this license, (2) the material is not modified, and (3) you do not charge a fee or require any other considerations for copies or for any works that incorporate…
69
Complex numbers have never been so intuitive to me
Imaginary numbers always confused me. Like understanding e, most explanations fell into one of two categories: Gee, what a great way to encourage math in…
70
Programming with Nothing (2011)
I love Ruby! I’ve used it every day for years and I’m not sick of it yet. It’s an easy language to love: it’s expressive, flexible and syntactically beautiful ; it has a unique combination of useful features like mixins , metaclasses and blocks ; it comes with a useful core library and comprehensive standard library …
71
72
AI solves International Math Olympiad problems at silver medal level
Breakthrough models AlphaProof and AlphaGeometry 2 solve advanced reasoning problems in mathematics
73
An Intuitive Guide to Linear Algebra (2012)
Despite two linear algebra classes, my knowledge consisted of "Matrices, determinants, eigen something something". Why? Well, let's try this course format:
74
Show HN: Interactive Essay on Signals, Sampling and the Fourier Transform
This text is designed to accompany your study of introductory digital signal processing. 1 It’s an eccentric piece of not-so-rigorous literature with a preoccupation for explaining things using interactive visualizations, animations and sound. 2 My goal is to explain the Discrete Fourier Transform using a miniature…
75
76
77
Numbering should start at zero (1982)
To denote the subsequence of natural numbers 2, 3, ..., 12 without the pernicious three dots, four conventions are open to us
78
Understanding LSTM Networks (2015)
Humans don’t start their thinking from scratch every second. As you read this essay, you understand each word based on your understanding of previous words. You don’t throw everything away and start thinking from scratch again. Your thoughts have persistence.
79
Mining Bitcoin with pencil and paper: 0.67 hashes per day
This article is now available in Japanese: 紙と鉛筆でビットコインをマイニング：1日に0.67ハッシュ and Russian: Майним Bitcoin с помощью бумаги и ручки . I decided...
80
Quake's Fast Inverse Square Root
I'm no graphics expert, but appreciate why square roots are useful. The Pythagorean theorem computes distance between points, and dividing by distance helps…
81
Yacc is dead: An update
The draft of " Yacc is Dead " that David Darais and I posted on arXiv received some attention, so we'd like to share updates and feedback.
82
Maze-generation algorithms, with JS demos
Algorithms, circle mazes, hex grids, masking, weaving, braiding, 3D and 4D grids, spheres, and more!
83
Bicycle
Interactive article explaining the physics of a bicycle.
84
85
The Dunning-Kruger effect is autocorrelation
Do unskilled people actually underestimate their incompetence?
86
Feynman vs. The Abacus
A Japanese man came into the restaurant. I had seen him before, wandering around; he was trying to sell abacuses. He started to talk to the waiters, and challenged them: He said he could add numbers faster than any of them could do.
87
Scott Aaronson explains his $200k bet (8 Signs A Claimed P≠NP Proof Is Wrong)
As of this writing, Vinay Deolalikar still hasn’t retracted his P≠NP claim, but a clear consensus has emerged that the proof, as it stands, is fatally flawed. The first reason is that weR…
88
Crit-bit Trees: the best way to store sets
A crit-bit tree can be used as a high-speed associative array. For example, an array mapping 54 to 1, 19 to 2, 99 to 3, 85 to 4, and 88 to 5 can be stored as a crit-bit tree containing 54=1, 19=2, 99=3, 85=4, and 88=5. The smallest string in the crit-bit tree larger than 85= is 85=4.
89
52 Factorial
They seem harmless enough, 52 thin slices of laminated cardboard with colorful designs printed on their sides. Yet, as another illustration of the mantra that complexity begins from the most simple systems, the number of variations that these 52 cards can produce is virtually endless. The richness of most playing card…
90