This essay is a write-up of my Professorial Inaugural Lecture, delivered at the London School of Economics on 9 December 2024. Herein, I describe how I became involved and have helped develop the field of behavioural public policy (BPP). I detail how the intellectual architecture of BPP – its journal, Annual International Conference and Association – came into existence, and allude to my hopes for how the field might develop as we go forward.

The genus Maculabatis is a group of batoid rays from the Dasyatidae family, consisting of two main complexes: the gerrardi (spotted species) and the pastinacoides (plain species). This study investigated the diversity within the Maculabatis gerrardi complex, revealing the presence of two distinct geographical lineages, with a potential new species captured off the coast of Mozambique. Molecular analysis showed a significant divergence: COI sequences from Mozambique specimens exhibited over 99% similarity with M. gerrardi from South Africa but more than 2% divergence from those in the Indo-Pacific. Phylogenetic analysis identified two distinct subclades, suggesting at least two hidden lineages within the genus Maculabatis and consequently possible new undescribed species within M. gerrardi complex. These findings emphasize the importance of conducting additional research that integrates both morphological and molecular methods to better understand the group's diversity and evolutionary dynamics, ultimately supporting the development of effective conservation strategies.

A core normative assumption of welfare economics is that people ought to maximise utility and, as a corollary of that, they should be consistent in their choices. Behavioural economists have observed that people demonstrate systematic choice inconsistences, but rather than relaxing the normative assumption of utility maximisation they tend to attribute these behaviours to individual error. I argue in this article that this, in itself, is an error – an ‘error error’. In reality, a planner cannot hope to understand the multifarious desires that drive a person’s choices. Consequently, she is not able to discern which choice in an inconsistent set is erroneous. Moreover, those who are inconsistent may view neither of their choices as erroneous if the context reacts meaningfully with their valuation of outcomes. Others are similarly opposed to planners paternalistically intervening in the market mechanism to correct for behavioural inconsistencies, and advocate that the free market is the best means by which people can settle on mutually agreeable exchanges. However, I maintain that policymakers have a legitimate role in also enhancing people’s agentic capabilities. The most important way in which to achieve this is to invest in aspects of human capital and to create institutions that are broadly considered foundational to a person’s agency. However, there is also a role for so-called boosts to help to correct basic characterisation errors. I further contend that government regulations against self-interested acts of behavioural-informed manipulation by one party over another are legitimate, to protect the manipulated party from undesired inconsistency in their choices.

In March 2024, Daniel Kahneman – the man who did perhaps more than anyone else to shape the field of behavioural public policy – died. He is among a small handful of scholars who have had a huge effect on my own career, and in this essay – the first in a series of essays in a special section of the Journal that honour him – I reflect on how his work inspired much of my own.

This study examines the use of graph centrality to identify critical components in assembly models, a method typically dominated by computationally intense analyses. By applying centrality measures to simulated assembly graphs, components were ranked to assess their criticality. These rankings were compared against Monte Carlo sensitivity analysis results. Preliminary findings indicate a promising correlation, suggesting graph centrality as a valuable tool in assembly analysis, enhancing efficiency and insight in critical component identification.

Clausen a prédit que le groupe des classes d’idèles de Chevalley d’un corps de nombres F apparaît comme le premier K-groupe de la catégorie des F-espaces vectoriels localement compacts. Cela s’est avéré vrai, et se généralise même aux groupes K supérieurs dans un sens approprié. Nous remplaçons F par une $\mathbb {Q}$-algèbre semi-simple, et obtenons le groupe des classes d’idèles noncommutatif de Fröhlich de manière analogue, modulo les éléments de norme réduite une. Même dans le cas du corps de nombres, notre preuve est plus simple que celle existante, et repose sur le théorème de localisation pour des sous-catégories percolées. Enfin, en utilisant la théorie des corps de classes, nous interprétons la loi de réciprocité d’Hilbert (ainsi qu’une variante noncommutative) en termes de nos résultats.

Clausen predicted that Chevalley’s idèle class group of a number field F appears as the first K-group of the category of locally compact F-vector spaces. This has turned out to be true and even generalizes to the higher K-groups in a suitable sense. We replace F by a semisimple $\mathbb {Q}$-algebra and obtain Fröhlich’s noncommutative idèle class group in an analogous fashion, modulo the reduced norm one elements. Even in the number field case, our proof is simpler than the existing one and based on the localization theorem for percolating subcategories. Finally, using class field theory as input, we interpret Hilbert’s reciprocity law (as well as a noncommutative variant) in terms of our results.

Changes in iceberg calving fluxes and oceanographic conditions around Antarctica have likely influenced the spatial and temporal distribution of iceberg fresh water fluxes to the surrounding ocean basins. However, Antarctic iceberg melt rate estimates have been limited to very large icebergs in the open ocean. Here we use a remote-sensing approach to estimate iceberg melt rates from 2011 to 2022 for 15 study sites around Antarctica. Melt rates generally increase with iceberg draft and follow large-scale variations in ocean temperature: maximum melt rates for the western peninsula, western ice sheet, eastern ice sheet and eastern peninsula are ~50, ~40, ~5 and ~5 m a−1, respectively. Iceberg melt sensitivity to thermal forcing varies widely, with a best-estimate increase in melting of ~24 m a−1°C−1 and range from near-zero to ~100 m a−1°C−1. Variations in water shear likely contribute to the apparent spread in thermal forcing sensitivity across sites. Although the sensitivity of iceberg melt rates to water shear prevents the use of melt rates as a proxy to infer coastal water mass temperature variability, additional coastal iceberg melt observations will likely improve models of Southern Ocean fresh water fluxes and have potential for subglacial discharge plume mapping.

Simulation is fundamental to many engineering design processes and powers the field of computational design. Simulation inherently consumes energy resulting in CO2 emissions that impact our environment. While one can source energy from renewable sources and use energy efficient hardware, efforts need to also be made in how we can use simulation in a sustainable manner.

This paper presents a sustainable simulation framework that borrows concepts from web services. The framework makes it easy for engineering firms to adopt and embed sustainable simulation practices thereby removing the burden from the designer tin thinking about how to design sustainably. An illustrative example reveals a 25% reduction in computational effort can be achieved by adopting the framework.

In this article, the confidence that has been placed in hard and, in particular, soft paternalistic measures in the field of behavioural public policy is questioned. The four purported limitations of human reasoning – i.e. limited imagination, willpower, objectivity and technical ability – are considered, but ultimately it is concluded that these are insufficient justifications for paternalistic intervention, for two principal-related reasons. First, it is impossible for a policy maker to discern what people desire for their own lives, and second, so long as they are not harming others, people ought to be free to pursue their own desires. The vision for the future of behavioural public policy proposed here is thus consistent with classical liberal, and in particular, Millian thought: i.e. aim to educate people on the pros and cons of their actions and inactions so that they are better equipped to live the lives they wish to lead but do not interfere directly in guiding them towards any particular end.