Why I don't believe that signs with fatality numbers cause more crashes

In a paper in Science, Jonathan Hall and Joshua Madsen proposed that dynamic signs that reported Texas road fatalities - “1669 deaths this year on Texas roads” - caused more accidents and fatalities. Recently, a friend mentioned the paper to me. I replied that I had seen the paper but didn’t believe the result. I wasn’t going to ignore the finding, but I would update my beliefs in only the smallest of ways.

Please not another bias: Take two

In my last post I discussed how I would like to redo my article “Please Not Another Bias! An Evolutionary Take on Behavioural Economics”. Apart from the removing the weak experimental evidence that I referenced, I wanted to make a few points more explicitly, such as the need for theory. Well, that re-write is here in the latest edition of Works in Progress. Not much has survived from the original except the opening framing and the continued belief that evolutionary theory will play a role in developing that theory.

Please not another bias: correcting the record

In 2015 I gave a presentation titled “Please Not Another Bias! An Evolutionary Take on Behavioural Economics” at the Marketing and Science Ideas Exchange (MSIX) conference. I posted my presentation on this blog, where it had around 100,000 readers in the first month (a lot for this blog). A copy of the post was the most popular post on Evonomics in its first year. I still see the post shared, which brings a slight cringe, as its not the article I would write today.

Revised course notes on Consumer Financial Decision Making

Last year I posted some notes for a course on Consumer Financial Decision Making. I have now refreshed those notes, but probably more usefully, also put them into book form using Quarto. Relative to this blog, which is built using markdown and Hugo, Quarto allows the incorporation of computation. It also allows for richer formatting and cross-referencing (without becoming the pain that is LaTeX), and easy production of an associated pdf.

Megastudy scepticism

0. Introduction In December last year Katherine Milkman and friends published a “megastudy” testing 54 interventions to increase the gym visits of 61,000 experimental participants. But more than just testing these interventions, the long list of authors stated: Policy-makers are increasingly turning to behavioural science for insights about how to improve citizens’ decisions and outcomes. Typically, different scientists test different intervention ideas in different samples using different outcomes over different time intervals.

Explaining base rate neglect

In a seminar for a team from an investment manager I described how base rates are often neglected when people are grappling with conditional probabilities. My description was somewhat confusing, so the below is a short write-up for the participants. – Consider the following question scenario. You test yourself with a rapid antigen test for COVID-19. The following information is known: The probability that a person has COVID-19 is 1% (the prevalence).

A bunch of links

A past regular feature of this blog was “A week of links’. Primarily, it was a useful way to aggregate interesting articles - I often search my blog posts for material (they are a collection of text files on my computer). But, the regularity of the feature drove my behaviour: I started looking for links for the post. So, I killed it. Now for the partial resurrection, with links posts to be delivered at random intervals to share articles or ideas that are worth a read.

Bankers are more honest than the rest of us

In an oft-quoted and cited Nature paper, Business culture and dishonesty in the banking industry, Cohn and colleagues argue that the culture in banking weakens and undermines the honesty norm. In the abstract they state: [W]e show that employees of a large, international bank behave, on average, honestly in a control condition. However, when their professional identity as bank employees is rendered salient, a significant proportion of them become dishonest.

My podcast appearances

Over the last few years I have appeared on several podcasts, the most recent being a discussion with Phil Agnew on the Nudge podcast. I am definitely more a writer than a speaker, but if you prefer audio to the written, check out the below. Nudge podcast - Beware of Behaviour Science BS 42courses - Behavioural Science & Evolutionary Biology Todd Nief - Loss Aversion and Ergodicity Economics: This was a long and pretty technical conversation on the back of a primer I wrote on ergodicity economics.

The outsider to the narrow-minded profession

I have always been a sucker for stories about an outsider tearing down what everyone believes to be true. With that, it’s no surprise that I have fond memories from my first read of M. Mitchell Waldrop’s book Complexity: The Emerging Science at the Edge of Order and Chaos (which must been around 20-years ago). The book is framed around the coalescence of a group of researchers into the Santa Fe Institute.