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Seeing the bulk: a primer on dimensionality reduction

datavis machine-learning math
If you haven’t seen Interstellar, you might not get the reference in the title. Don’t sweat it, the bulk beings are some advanced civilization that is able to move outside the familiar 3D space that we are stuck in. A similar plot device was used in Edwin Abbott’s book Flatland. Outside of entertainment, there is a lot of value in attempting to understand high dimensional spaces. Physics, machine learning, and engineering control systems all make use of higher-dimensional spaces in one way or another. Read more...

word embeddings and semantics

Can a machine understand what a word means? Right now machines routinely correct spelling and grammar, but are pretty useless when it comes to semantics. Search engines are an exception, they have a rudimentary understanding of what words mean. One of the ways this can work is explored in Tomas Mikolov’s 2013 paper on word embeddings. Word embeddings are mappings from sets of words to vectors, such that the distances between the vectors represent the semantic similarity of the words. Read more...

Thing explainer in emacs

This is my first major mode for emacs. It was inspired by Randall Munroe’s Thing Explainer and Morten Just’s editor that doomed humanity. The concept is simple, restrict your vocabulary to the 1000 most common words. If you can explain something using this reduced vocabulary, then you really understand the topic. This is a decent test of understanding because it’s easy to learn a word, and even use that word in the right context, but still have no idea how it relates to other things. Read more...

Dockerize all the things

Okay, maybe not all the things, but the things that tend to litter your filesystem with libraries, dependencies and other crap that increases the chances of a conflict. If you are not familiar with Docker, check it out, then come back here and troll my flaming fanboy drunk on kool aid ravings in the comments. I write a lot of ruby and python code, and I also use a lot of ruby/python and javascript code other people wrote as well. Read more...

New largest Mersenne prime found

The largest prime number was just found, and it is a Mersenne prime, or a prime number of the form 2n - 1. As of January 2016, 274,207,281 - 1 is the largest known prime. Primes are interesting in their own right, but they also are indispensible in cryptography. We’ve known since Euclid that the number of primes is infinite, but it is still an open problem whether the number of Mersenne primes is infinite: Read more...

Set up Mailinabox with LetsEncrypt

If you are not familiar with the EFF or their great project LetsEncrypt, don’t feel bad, even the CEO of T-Mobile doesn’t know. But seriously, this post is about combining the best of two projects: Mailinabox a standalone mail server that enables email as it should be LetsEncrypt a non-profit TLS certificate authority Mailinabox allows anyone with little patience to set up their own mail server with all the fixings, web client, spam filter, admin panel, etc. Read more...

How to set up LetsEncrypt (free SSL/TLS certs)

First, for those who don’t know what LetsEncrypt is, it is a project by the EFF to create a legitimate certificate authority that doesn’t charge. Up until now, certificate authorities charged, creating a financial barrier for many to use SSL/TLS to secure their site. It’s true that the prices weren’t unreasonable, but it’s just enough to prevent many people from choosing to reap the benefits of encryption. As far back as 2012, Jeff Atwood argued in a blog post that we should make SSL default for web pages, but acknowledged that it would take a while for it to be the default: Read more...

Making a Go Game for the Web

I’ve been feeling productive in the last few weeks. I just finished two Coursera classes, one in machine learning and one in Swift programming. I also finished my minimum viable go game: goga.me. And we are working on a really exciting feature at work. I really like having lots of interesting things to work on. Anyway, enough feelings, you came here for games and code. The game of Go is ancient, it has very few rules, but an unfathomable level of complexity emerges from all the possible ways the pieces can be put on the board. Read more...

Gun control and safety

Another mass shooting happened today. I don’t usually write about this, but it happened in Roseberg, Oregon, close to where I live. Too close. I do understand that it is morally equivalent to a mass shooting in Ethiopia, Indonesia, the Netherlands or Australia, but something about events being close by have a bigger emotional impact. The question I want to address in this article is whether legislation can help solve this problem. Read more...

Review: The Warmth of Other Suns by Isabel Wilkerson

Isabel Wilkerson’s riveting book about the Great Migration of African-Americans out of the south is the perfect blend of narrative and statisitcs. The personal stories of Ida Mae Brandon Gladney, George Swanson Starling and Robert Joseph Pershing Foster are the substantive bulk of the book. Around these personal stories are statistics that serve to add context and clarity to a movement that was so large, and took place over a long enough time, that it’s easy to miss it as a distinct historical period. Read more...
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Computer programmer and amateur mathematician. Lives in rainy Portland, Oregon, United States. Read more

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