Years ago, during the start of covid, I wanted to replicate the Arduino magnetic levitation system I saw my colleague build back in 2009. I know almost nothing about electrical engineering or control systems and when I tried this in 2020 I…

On a few occasions I’ve been fortunate enough to live within biking distance of a surf break. One of my favorite activities to do in this situation is outfit a bicycle with a surfboard rack and use it for transportation to the beach.

I’ve decided to move my political blogging to a different site, https://prop13.wtf. Check it out! All kinds of cool stuff like tax assessments vs. rent in Los Angeles:

I finally got around to enabling https here. Some notes: Namecheap sells ssl certs via PositiveSSL/Comodo. I thought this would be easiest but they don’t really work with AWS.

First post in 5+ years! I used to use s3_website to publish this blog. Turns out that project has been deprecated with nothing to replace it. Oh well.

The below image shows 1024 of the captcha photos used in “I’m not a human: Breaking the Google reCAPTCHA” by Sivakorn, Polakis, and Keromytis arranged on a 32x32 grid in such a way that visually-similar photos appear in close proximity to…

Check out this video of my talk at the NYC Machine Learning meetup. It’s based on this blog post and the deck is here.

Here’s a plot of the cumulative number of upvotes per minute for submissions to a few major subreddits:

Last year Chris Whong used a foil request to obtain a dataset with information on the locations, times, and medallions for 173 million NYC cab rides. I’m interested is determining which cabs are the fastest cabs are and how quickly they can…

Last week at Clarifai we formally announced our Not Safe for Work (NSFW) adult content recognition model. Automating the discovery of nude pictures has been a central problem in computer vision for over two decades now and, because of it’s…

The Evolution darknet marketplace was an online black market which operated from January 2014 until Wednesday of last week when it suddenly disappeared. A few days later, in a reddit post, gwern released a torrent containing daily wget…

Altmetrics link Earlier this week I updated a paper on the arxiv: http://arxiv.org/abs/1404.7152. The paper appeared a few months ago at IEEE BigData 2014 and was the subject of all my talks last year. This update syncs the arxiv paper with…

I’ve been using Open Torque Viewer combined with the Torque App and a basic OBDII bluetooth sensor to log my car’s sensor data over the past month and a half. Here are a few things that I’ve learned:

Update 2015-03-25: We just got nominated for a best paper award! Update 2015-04-01: We won best paper! Patrick Park and I recently got our paper accepted into SBP 2015. The work demonstrates how the structure of Twitter @mention networks…

I was looking for a way to identify urls in text and eventually found this huge regex http://daringfireball.net/2010/07/improved_regex_for_matching_urls . I figured I’ll need to do this again so I stuck all that into urlmarker.py and now I…

Hearddit is a Soundcloud/Spotify/reddit bot that builds playlists from links posted on music subreddits. I built the bot since I was getting tired of the twenty or so tracks that the internet radio collaborative filters decided I liked and…

Here’s a plot of the political blogging network in “The political blogosphere and the 2004 US Election” but with the edge bundles determined using a stochastic block model (remark: the below plot is the same (ie. same layout and data) as…

Here’s a plot of the political blogging network described by Adamic and Glance in “The political blogosphere and the 2004 US Election”. The layout is determined using graph-tool’s implementation of hierarchal edge bundles. The color scheme…

Just came across this very easy library for community detection https://sites.google.com/site/findcommunities/ https://bitbucket.org/taynaud/python-louvain/src. Here’s how to create a graph, detect communities in it, and then visualize with…

A few minor bug fixes were in order since Twitter started requiring SSL to access their API (which happened in January, meaning my app has been broken for 6 months now…). Get a copy of the only app that makes it so easy to surf report that…

I recently published a paper on the arxiv: http://arxiv.org/abs/1406.2392, earlier this month it was accepted into the ChASM workshop at WebSci. Here’s the abstract:

After stressing my reading comprehension over the past eight months I’ve finally finished David Foster Wallace’s Infinite Jest. The writing is, in a word, impressive. Wallace’s command of the English language allows him to do things that…

For the FFT sonification I needed to implement my own FFT in order to keep track of which notes are being played while the Fourier transform executes. It turns out that implementing an FFT isn’t too difficult as long as you don’t care how…

Brian and I recently published a paper on the arxiv: http://arxiv.org/abs/1405.5924, earlier this month it was accepted into the ChASM workshop at WebSci. Here’s the abstract:

This really threw me off for a while (cf https://stackoverflow.com/questions/23748254/storing-a-kryo-object-in-a-compiled-jar ). I had a HashMap I needed to persist and have fast access to. I used Kryo to serialize the object

I recently published a paper on the arxiv: http://arxiv.org/abs/1404.7152, and it made Tech Review junior varsity! Here’s the abstract: Geographically annotated social media is extremely valuable for modern information retrieval. However…

The FFT is an essential tool for digital signal processing and electronic music production. It is easily, commonly, and inefficiently implemented via the recursive Cooley-Tukey algorithm which we now briefly review.

One second of a 44.1kHz single channel .wav file can be read into an array (call it b) of length 44100. Given a matrix A we seek solutions to the system Ax=b. Through iterations of Gauss-Seidel the vector Ax will approach b with the high…

Suppose you drop a set of drums and they land randomly ordered in a row on the floor. You want to put the drums back in order but can only pick up and swap two at a time. A good strategy to minimize the number of swaps you must make is to…

I’ve been using Spark for a few months now. It’s great for tasks that don’t fit easily into a Pig script. If you’ve already been writing Java for a while it can be a drag to switch everything over to sbt just for Spark.

This notebook contains notes and beliefs about several commonly-used supervised learning algorithms. My dream is that it will be useful as a quick reference or for people who are irrational about studying for machine learning interviews.