The mathematical principles of management

I've read about 100 management books by now but if there's something that always bothered me it's the lack of first principles thinking.

From: Erik Bernhardsson

The eigenvector of "Why we moved from language X to language Y"

I was reading yet another blog post titled “Why our team moved from <language X> to <language Y>” (I forgot which one) and I started wondering if you can generalize it a bit. Is it possible to generate a N * N contingency table of moving from language X to language Y?

From: Erik Bernhardsson

Why I went into the mortgage industry

I just realized last Thursday that I have spent two full years at Better, incidentally on the same day as we announced a $15M round led by Kleiner Perkins. So it was a good point to reflect a bit and think back – what the F led me to abandon my role managing the machine learning team at Spotify?

From: Erik Bernhardsson

Language pitch

Here's a fun analysis that I did of the pitch (aka.

From: Erik Bernhardsson

Functional programming is the libertarianism of software engineering

This is a pretty dumb post, in which I argue that functional programming has a lot of the bad parts of libertarianism and a lot of the good parts: Both ideologies strive to eliminate [the] state.

From: Erik Bernhardsson

The half-life of code & the ship of Theseus

As a project evolves, does the new code just add on top of the old code? Or does it replace the old code slowly over time? In order to understand this, I built a little thing to analyze Git projects, with help from the formidable GitPython project.

From: Erik Bernhardsson

Are data sets the new server rooms?

This blog post Data sets are the new server rooms makes the point that a bunch of companies raise a ton of money to go get really proprietary awesome data as a competitive moat. Because once you have the data, you can build a better product, and no one can copy it (at least not very cheaply).

From: Erik Bernhardsson

Pareto efficency

Pareto efficiency is a useful concept I like to think about. It often comes up when you compare items on multiple dimensions. Say you want to buy a new TV. To simplify it let's assume you only care about two factors: price and quality.

From: Erik Bernhardsson

State drift

I generally haven't written much about software architecture.

From: Erik Bernhardsson

When machine learning matters

I joined Spotify in 2008 to focus on machine learning and music recommendations. It's easy to forget, but Spotify's key differentiator back then was the low-latency playback. People would say that it felt like they had the music on their own hard drive.

From: Erik Bernhardsson

Subway waiting math

Why does it suck to wait for things? In a previous post I analyzed a NYC subway dataset and found that at some point, quite early, it's worth just giving up. This isn't a proof that the subway doesn't run on time – in fact it might actually proves that the subway runs really well.

From: Erik Bernhardsson

Approximate nearest news

As you may know, one of my (very geeky) interests is Approximate nearest neigbor methods, and I'm the author of a Python package called Annoy. I've also built a benchmark suite called ann-benchmarks to compare different packages.

From: Erik Bernhardsson

What is your motivation?

I've been trying to learn Clojure. I keep telling people I meet that I really want to learn Clojure, but still every night I can't get myself to spend time with it. It's unclear if I really want to learn Clojure or just want to have learned Clojure?

From: Erik Bernhardsson

Dollar cost averaging

(I accidentally published an unfinished draft of this post a few days ago – sorry about that). There's a lot of sources preaching the benefits of dollar cost averaging, or the practice of investing a fixed amount of money regularly.

From: Erik Bernhardsson

Why organizations fail

One of my favorite business hobbies is to reduce some nasty decision down to its absolute core objective, decide the most basic strategy, and then add more and more modifications as you have to confront the complexity of reality (yes I have very lame hobbies thanks I know).

From: Erik Bernhardsson

NYC subway math

Apparently MTA (the company running the NYC subway) has a real-time API. My fascination for the subway takes autistic proportions and so obviously I had to analyze some of the data. The documentation is somewhat terrible, but here's some relevant code for how to use the API:

From: Erik Bernhardsson

Exploding offers are bullshit

I do a lot of recruiting and have given maybe 50 offers in my career. Although many companies do, I never put a deadline on any of them. Unfortunately, I've often ended up competing with other companies who do, and I feel really bad that this usually tricks younger developers into signing offers.

From: Erik Bernhardsson

Meta-blogging

(This is not a very relevant/useful post for regular readers – feel free to skip. I thought I would share it so people can find it on Google.) My blog blew up twice in a week earlier this year when I landed on Hacker News.

From: Erik Bernhardsson

Iterate or die

Here's a conclusion I've made building consumer products for many years: the speed at which a company innovates is limited by its iteration speed. I don't even mean throughput here. I just mean the cycle time.

From: Erik Bernhardsson

My issue with GPU-accelerated deep learning

I've been spending several hundred bucks renting GPU instances on AWS over the last year. The speedup from a GPU is awesome and hard to deny. GPUs have taken over the field. Maybe following the footsteps of Bitcoin mining there's some research on using FPGA (I know very little about this).

From: Erik Bernhardsson