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What is a win vector?

From time to time we are asked “what is the company name Win-Vector LLC referring to?” It is a cryptic pun trying to be an encoding of “we deliver victory.”

The story is an inside joke referring to something really only funny to one of the founders. But a joke that amuses the teller is always enjoyed by at least one person. Win-Vector LLC’s John Mount had the honor of co-authoring a 1997 paper titled “The Polytope of Win Vectors.” The paper title is obviously mathematical terms in an odd combination. However the telegraphic grammar is coincidentally similar to deliberately ungrammatical gamer slang such as “full of win” and “so much win.”

2829551 full of win

If we treat “win” as a concrete noun (say something you can put in a sack) and “vector” in its non-mathematical sense (as an entity of infectious transmission) we have “Win-Vector LLC is an infectious delivery of victory.” I.e.: we deliver success to our clients. Of course, we have now attempt to explain a weak joke. It is not as grand as “winged victory,” but it does encode a positive company value: Win-Vector LLC delivers successful data science projects and training to clients.

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Winged Victory: from Wikipedia

Let’s take this as an opportunity to describe what a win vector is. Continue reading What is a win vector?

Posted on Categories Computer Science, Expository Writing, RantsTags , , 3 Comments on A randomized algorithm that fails with near certainty

A randomized algorithm that fails with near certainty

Recently Heroku was accused of using random queue routing while claiming to supply something similar to shortest queue routing (see: James Somers – Heroku’s Ugly Secret and more discussion at hacker news: Heroku’s Ugly Secret). If this is true it is pretty bad. I like randomized algorithms and I like queueing theory, but you need to work through proofs or at least simulations when playing with queues. You don’t want to pick an arbitrary algorithm and claim it works “due to randomness.” We will show a very quick example where randomized routing is very bad with near certainty. Just because things are “random” doesn’t mean you can’t or shouldn’t characterize them. Continue reading A randomized algorithm that fails with near certainty

Posted on Categories Computer Science, Expository Writing, MathematicsTags , , , ,

Ergodic Theory for Interested Computer Scientists

We describe ergodic theory in modern notation accessible to interested computer scientists.

The ergodic theorem ( theory (link)) is an important principle of recurrence and averaging in dynamical systems. However, there are some inconsistent uses of the term, much of the machinery is intended to work with deterministic dynamical systems (not probabilistic systems, as is often implied) and often the conclusion of the theory is mis-described as its premises.

By “interested computer scientists” we mean people who know math and work with probabilistic systems1, but know not to accept mathematical definitions without some justification (actually a good attitude for mathematicians also). Continue reading Ergodic Theory for Interested Computer Scientists