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I recently read John Kay and Mervyn King’s book Radical Uncertainty as part of an economics book club and I thought I would share some thoughts on the book here. I’ve never read anything by John Kay before, but this is the second book by King which I have read, after The End of Alchemy , which is about banking regulation. Radical Uncertainty is about statistics, and especially about the problems…
I came across a post recently by a machine learning engineer who made the bold claim that logistic regression is the worst name for an algorithm ever, or something along those lines 1 . Many statisticians of the more old-school type seemed to disagree. This led me to think a bit more deeply about the subject. I’ve already written several posts on bad terminology in statistics (see confidence level…
This is a continuation of my previous post about certain algebraic structures. We defined a telephone algebra (I’m still wondering what its real name is) to be a triple $(A, \ominus, e)$ where $A$ is a set, $\ominus$ is a binary operation on $A$, and $e \in A$ is a distinguished element, such that the axioms $x \ominus e = x$ and $x \ominus (x \ominus y) = y$ hold for all $x, y \in A$. An example…
I have a couple of posts lined up about statistics and economics, but it’s been a while since I wrote anything about mathematics. The term telephone numbers in the title of this post doesn’t refer to numbers which uniquely identify telephones. Rather, it refers to numbers which count how many involutions there are on a set of a given size. More on that later! I recently came across a paper by…
I recently found a useful tutorial on AWS S3 in R at a blog called Notes from a Data Witch . One thing I liked about this blog is that includes a BibTeX citation for each post in case a reader wants to copy and paste the citation information. Some students at Auckland University recently told me that they have been using my DSGE tutorial so I decided that it would be a good idea if I had a…
Introduction: Copyright Law and Whatnot I recently watched a clip from a debate between Timothy Nguyen of Google Deepmind and Danish author Janne Teller . The debate, entitled Technology and Freedom , took place at Hay-on-Wye in summer 2025. On the subject of copyright, Nguyen says: The reason AI is so powerful is because it’s scraped all this data on the internet and of course that has all these…
This post is a simple demo of how to embed a Quarto presentation in your website. Quarto is a pretty nice open-source scientific publishing system which enables you to make presentations (powered by revealjs ). It’s available by default in recent versions of RStudio. I was recently invited to present one of my models at the Ministry of Transport Te Manatū Waka in New Zealand, and I thought it was…
Johann Heinrich von Thünen (1783-1850) was a German agronomist, agricultural reformer, and textbook author. If you look his name up on the internet, you’ll find that he is best remembered for his model of land use, which seems to have made its way onto the Advanced Placement Geography syllabus in the United States. However, this wasn’t always the case. In a 1955 essay , George Stigler wrote: We…
This is a post about the famous double descent phenomenon in machine learning. I aim to construct the simplest possible example of double descent and explain exactly how it arises and why it doesn’t contradict the bias-variance tradeoff. I was inspired to write this post by an excellent video by Welch Labs entitled What the Books Get Wrong about AI . Despite the provocative title, the video…
This post is about economic growth in a region in which labour is free to move around. A colleague recently showed me a paper by Capasso, Engbers and La Torre which describes an extension of the Solow growth model in which a spatial element is added. It seemed to me that the model could be extended in various ways. Most interestingly, the paper only gave an example in which capital and labour move…