Posts with the tag maths:

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 $f(x)$.

pq-Formula

We want to find $a_1$ and $a_2$ using only $p$ and $q$

Intuitive Indexing

While most programming languages use 0-based indexing some people are not convinced that this is a good thing and not just the legacy of the language C. They argue that starting to index with one is more intuitive than starting to index with zero, and that there is no good reason to use 0-based indices besides pointer arithmetic which should not be of concern to higher level programming.

And to be fair, proponents of zero based indexing have mostly failed to provide a convincing argument for their preference (Dijkstra’s range argument aside). To remedy this, I am going to present 5 arguments for 0-based indexing and address the intuition argument of 1-based indexing.