Housing

If housing supply stays constant and there is more demand for housing than available, then prioritization is necessary. Allocation priority is often assigned either by

  • willingness to pay induced by a market economy,
  • or first come, first serve induced by rent caps.

Livable Cities vs. Cars

Cars take tons of space While bike paths and especially public transport have significantly more throughput, more space is allocated to cars. This is fundamentally unfair. And this does not even account for the stupendous amount of space cars occupy while parked. Why do people move to the suburbs? They want to escape cars. Well, they are going to say they want to escape the noise and have easy access to nature. But cities are not loud, cars are. Here is a video of someone taking noise measurements and if we removed two car lanes and all parking, we could add tons of greenery to every street.

Version Control with Git

When choosing a programming language or database, there are so many options to choose from. And people regularly create new options since they are not happy with the existing ones. But for version control, there exists essentially just one option: Git. And while it takes some getting used to, it must do something right, if nobody wants to spend the effort to improve upon it. This is a small introduction.

Pragmatic Positive Image of People

Cynical people like to call me naive, whenever I suggest how good or neutral intentions could have lead to a situation where they suspect malice. But naivety implies there would be no thought behind assuming best intentions, just lack of experience. And this is not the case.

Proof Assistants for Typesetting Maths

I am currently trying make our exercise sheets HTML based to allow for things like drop down solutions, which start in a collapsed state. I ended up asking myself whether it might be possible yet to verify proofs submitted by students automatically. So I looked for Proof Assistants and ended up with lean. In particular I tried out the Natural Numbers Game and started reading Theorem Proving in Lean for a more comprehensive introduction. Landmark based Maths vs Steps in Proof Assistants The first contrast I noticed was the following. When you write down Maths for another human, you tend to write something like:

Bayes Helper

If you use a test with 95% sensitivity and 95% specificity, and it is positive then you are surly more likely sick than not, right? Well, ... it depends. On the prior probability to be sick (or prevalence) to be precise. And humans are really bad assessing the meaning of a test result.

Why Disease Spreads Exponentially

If there is one thing this pandemic has taught us, then it is that few people truly understand exponential growth. This post is an attempt to explore this magical function with minimal prerequisites.

Introduction to Probability

Probability theory is best understood through the lense of “the expected value”. We are fundamentally trying to understand what we can expect so the expected value is a great place to start

Matrix Multiplication

Linear functions define matrix multiplication and make matrices and linear functions effectively interchangeable.

Taylor Approximation

Let’s say we want to approximate a function $f$. In an area around $a$ the value $f(a)$ is probably a decent approximation for $f(x)$.