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August 5, 2025

EPA removal of vehicle emissions limits won’t stop the shift to electric vehicles, but will make it harder, slower and more expensive

Source: The Conversation – USA (2) – By Alan Jenn, Associate Professor of Civil and Environmental Engineering, University of California, Davis

Customers have embraced electric vehicles; policy changes may decrease that interest but will not eliminate it. Carlin Stiehl/Los Angeles Times via Getty Images

The U.S. government is in full retreat from its efforts to make vehicles more fuel-efficient, which it has been waging, along with state governments, since the 1970s.

The latest move came on July 29, 2025, when the Environmental Protection Agency said it planned to rescind its landmark 2009 decision, known as the “endangerment finding,” that greenhouse gases pose a threat to public health and welfare. If that stands up in court and is not overruled by Congress, it would undo a key part of the long-standing effort to limit greenhouse gas emissions from vehicles.

As a scholar of how vehicle emissions contribute to climate change, I know that the science behind the endangerment finding hasn’t changed. If anything, the evidence has grown that greenhouse gas emissions are warming the planet and threatening people’s health and safety. Heat waves, flooding, sea-level rise and wildfires have only worsened in the decade and a half since the EPA’s ruling.

Regulations over the years have cut emissions from power generation, leaving transportation as the largest source of greenhouse gas emissions in the U.S.

The scientific community agrees that vehicle emissions are harmful and should be regulated. The public also agrees, and has indicated strong preferences for cars that pollute less, including both more efficient gas-burning vehicles and electric-powered ones. Consumers have also been drawn to electric vehicles thanks to other benefits such as performance, operation cost and innovative technologies.

That is why I believe the EPA’s move will not stop the public and commercial transition to electric vehicles, but it will make that shift harder, slower and more expensive for everyone.

A multilane highway is packed with cars and trucks. — Transportation is the largest source of greenhouse gas emissions in the U.S.
Brandon Bell/Getty Images

Putting carmakers in a bind

The most recent EPA rule about vehicle emissions was finalized in 2024. It set emissions limits that can realistically only be met by a large-scale shift to electric vehicles.

Over the past decade and a half, automakers have been building up their capability to produce electric vehicles to meet these fleet requirements, and a combination of regulations such as California’s zero-emission-vehicle requirements have worked together to ensure customers can get their hands on EVs. The zero-emission-vehicle rules require automakers to produce EVs for the California market, which in turn make it easier for the companies to meet their efficiency and emissions targets from the federal government. These collectively pressure automakers to provide a steady supply of electric vehicles to consumers.

The new EPA move would undo the 2024 EPA vehicle-emissions rule and other federal regulations that also limit emissions from vehicles, such as the heavy-duty vehicle emissions rule.

The possibility of a regulatory reversal puts automakers into a state of uncertainty. Legal challenges to the EPA’s shift are all but guaranteed, and the court process could take years.

For companies making decade-long investment decisions, regulatory stability matters more than short-term politics. Disrupting that stability undermines business planning, erodes investor confidence and sends conflicting signals to consumers and suppliers alike.

An aerial view shows a very large building with an even larger parking lot outside, filled with cars. — Car manufacturers in the U.S. have invested large sums of money to produce electric vehicles.
Elijah Nouvelage/Getty Images

A slower roll

The Trump administration has taken other steps to make electric vehicles less attractive to carmakers and consumers.

The White House has already suspended key provisions of the Inflation Reduction Act that provided tax credits for purchasing EVs and halted a US$5 billion investment in a nationwide network of charging stations. And Congress has retracted the federal waiver that allowed California to set its own, stricter emissions limits. In combination, these policies make it hard to buy and drive electric vehicles: Fewer, or no, financial incentives for consumers make the purchases more expensive, and fewer charging stations make travel planning more challenging.

Overturning the EPA’s 2009 endangerment finding would remove the legal basis for regulating climate pollution from vehicles altogether.

But U.S. consumer interest in electric vehicles has been growing, and automakers have already made massive investments to produce electric vehicles and their associated components in the U.S. – such as Hyundai’s EV factory in Georgia and Volkswagen’s Battery Engineering Lab in Tennessee.

Global markets, especially in Europe and China, are also moving decisively toward electrifying large proportions of the vehicles on the road. This move is helped in no small part due to aggressive regulation by their respective governments. The results speak for themselves: Sales of EVs in both the European Union and China have been growing rapidly.

But the pace of change matters. A slower rollout of clean vehicles means more cumulative emissions, more climate damage and more harm to public health.

The EPA’s proposal seeks to slow the shift to electric vehicles, removing incentives and raising costs – even though the market has shown that cleaner vehicles are viable, the public has shown interest, and the science has never been clearer. But even such a major policy change can’t stop the momentum of those trends.

Alan Jenn does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. EPA removal of vehicle emissions limits won’t stop the shift to electric vehicles, but will make it harder, slower and more expensive – https://theconversation.com/epa-removal-of-vehicle-emissions-limits-wont-stop-the-shift-to-electric-vehicles-but-will-make-it-harder-slower-and-more-expensive-262384

August 5, 2025

When it comes to finance, ‘normal’ data is actually pretty weird

Source: The Conversation – USA (2) – By D. Brian Blank, Associate Professor of Finance, Mississippi State University

When business researchers analyze data, they often rely on assumptions to help make sense of what they find. But like anyone else, they can run into a whole lot of trouble if those assumptions turn out to be wrong – which may happen more often than they realize. That’s what we found in a recent study looking at financial data from about a thousand major U.S. companies.

One of the most common assumptions in data analysis is that the numbers will follow a normal distribution – a central concept in statistics often known as the bell curve. If you’ve ever looked at a chart of people’s heights, you’ve seen this curve: Most people cluster near the middle, with fewer at the extremes. It’s symmetrical and predictable, and it’s often taken for granted in research.

A one-minute introduction to the concept of the bell curve.

But what happens when real-world data doesn’t follow that neat curve?

We are professors who study business, and in our new study we looked at financial data from public U.S. companies – things like firm market value, market share, total assets and similar financial measures and ratios. Researchers often analyze this kind of data to understand how companies work and make decisions.

We found that these numbers often don’t follow the bell curve. In some cases, we found extreme outliers, such as a few large firms being thousands of times the size of other smaller firms. We also observe distributions that are “right-skewed,” which means that the data is bunched up on the left side of the chart. In other words, the values are on the lower end, but there are a few really high numbers that stretch the average upward. This makes sense, because in many cases financial metrics can only be positive – you won’t find a company with a negative number of employees, for example.

Why it matters

If business researchers rely on flawed assumptions, their conclusions – about what drives company value, for example – could be wrong. These mistakes can ripple outward, influencing business decisions, investor strategies or even public policy.

Take stock returns, for example. If a study assumes those returns are normally distributed, but they’re actually skewed or full of outliers, the results might be distorted. Investors hoping to use that research might be misled.

Researchers know their work has real-life consequences, which is why they often spend years refining a study, gathering feedback and revising the article before it’s peer-reviewed and prepared for publication. But if they fail to check whether data is normally distributed, they may miss a serious flaw. This can undermine even otherwise well-designed studies.

In light of this, we’d encourage researchers to ask themselves: Do I understand the statistical methods I’m using? Am I checking my assumptions – or just assuming they’re fine?

What still isn’t known

Despite the importance of data assumptions, many studies fail to report tests for normality. As a result, it’s unclear how many findings in finance and accounting research rest on shaky statistical grounds. We need more work to understand how common these problems are, and to encourage best practices in testing and correcting for them.

While not every researcher needs to be a statistician, everyone using data would be wise to ask: How normal is it, anyway?

The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.

– ref. When it comes to finance, ‘normal’ data is actually pretty weird – https://theconversation.com/when-it-comes-to-finance-normal-data-is-actually-pretty-weird-259365

August 5, 2025

Why leisure matters for a good life, according to Aristotle

Source: The Conversation – USA (3) – By Ross Channing Reed, Lecturer in Philosophy, Missouri University of Science and Technology

What we do in our free time says a lot about what makes us happy. Halfpoint Images/Moment via Getty Images

In his powerful book “The Burnout Society,” South Korean philosopher Byung-Chul Han argues that in modern society, individuals have an imperative to achieve. Han calls this an “achievement society” in which we must become “entrepreneurs” – branding and selling ourselves; there is no time off the clock.

In such a society, even leisure risks becoming another kind of work. Rather than providing rest and meaning, leisure is often competitive, performative and exhausting.

People feeling pressure to self-promote, for example, might spend their free time posting photos of an athletic race or an elaborate vacation on social media
to be viewed by family, friends and potential employers, adding to exhaustion and burnout.

As a philosopher and philosophical counselor, I study connections between unhealthy forms of leisure and burnout. I have found that philosophy can help us navigate some of the pitfalls of leisure in an achievement society. The celebrated Greek philosopher Aristotle, who lived from 384 to 322 B.C.E., in particular, can offer important insights.

Aristotle on self-development

Aristotle begins the famous “Nicomachean Ethics” by pointing out that we are all searching for happiness. But, he says, we are often confused about how to get there.

A man running outdoors on a paved pathway surrounded by palm trees and buildings. — Exercise needs to be done in moderation to achieve health goals.
AzmanL/E+ via Getty images

Aristotle believed that pleasure, wealth, honor and power will not ultimately make us happy. True happiness, he said, required ethical self-development: “Human good turns out to be activity of soul in accordance with virtue.”

In other words, if we want to be happy, Aristotle contended, we must make reasoned choices to develop habits that, over time, become character traits such as courage, temperance, generosity and truthfulness.

Aristotle is explicitly linking the good life to becoming a certain kind of person. There is no shortcut to ethical self-development. It takes time – time off the clock, time not engaged in some kind of entrepreneurial self-promotion.

Aristotle is also telling us about the power of our choices. Habits, he argues, are not just about action, but also motives and character. Our actions, he says, actually change our desires. Aristotle says: “By abstaining from pleasures we become temperate, and it is when we have become so that we are most able to abstain from them.”

In other words, good habits are the result of moving incrementally in the right direction through practice.

For Aristotle, good habits lead to ethical self-development. The converse is also true. To this end, for Aristotle, having good friends and mentors who guide and support moral development are essential.

How Aristotle helps us understand leisure

In an achievement society, we are often conditioned to respond to external pressures to self-promote. We may instead look to pleasure, wealth, honor and power for happiness. This can sidetrack the ethical development required for true happiness.

True leisure – leisure that is not bound to the imperative to achieve – is time we can reflect on our real priorities, cultivate friendships, think for ourselves, and step back and decide what kind of life we want to live.

The Greek word “eudaimonia,” often translated simply as happiness, is the term Aristotle uses to describe human thriving and flourishing. According to philosopher Jane Hurly, Aristotle views “leisure as essential for human thriving.” Indeed, “for both Plato and Aristotle leisure … is a prerequisite for the achievement of the highest form of human flourishing, eudaimonia,” as philosopher Thanassis Samaras argues.

While we may have limited means to acquire pleasure, wealth, honor and power, Aristotle tells us that we have control over the most important variable in the good life: what kind of person we will become. Leisure is crucial because it is time in which we get to decide what kind of habits we will develop and what kind of person we will become. Will we capitulate to achievement society? Or utilize our free time to develop ourselves as individuals?

When leisure is preoccupied with entrepreneurial self-promotion, it is difficult for moral development to take place. Free time that is not hijacked by the imperative to achieve is required for the development of a consistent relationship to oneself – what I call a relationship of self-solidarity – a kind of reflective self-awareness necessary to aim at the right target and make moral choices. Without such a relationship, the good life will remain elusive.

Leisure reimagined

Rather than adopting the achievement society’s formulation of the good life, we may be able to formulate our own vision. Without one’s own vision, we risk becoming mired in bad habits, leading us away from the moral development through which the good life becomes possible.

Aristotle makes it clear that we have the power to change not only our behaviors but our desires and character. This self-development, as Aristotle writes, is a necessary part of the good life – a life of eudaimonia.

The choices we make in our free time can move us closer to eudaimonia. Or they could move us in the direction of burnout.

Ross Channing Reed does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. Why leisure matters for a good life, according to Aristotle – https://theconversation.com/why-leisure-matters-for-a-good-life-according-to-aristotle-260392

August 5, 2025

Football and faith could return to the Supreme Court – this time, over loudspeakers

Source: The Conversation – USA (3) – By Charles J. Russo, Joseph Panzer Chair in Education and Research Professor of Law, University of Dayton

Private schools want to pray over the loudspeaker – at a public facility, during games run by a state association. John Coletti/Photodisc via Getty Images

With the start of another high school football season around the corner, a long-simmering dispute has heated up: prayers at games.

Kennedy v. Bremerton, the case of a high school football coach praying on the field after games, has been in the spotlight since the Supreme Court’s 2022 ruling. But another football controversy first emerged in 2015, when two Christian schools in Florida made it to the state championships. The games were run by the state’s high school athletic association, a government body.

Association officials barred the teams from conducting a joint prayer over the loudspeaker at the public stadium before kickoff. Allowing a prayer, they said, would violate federal and constitutional law. The First Amendment’s establishment clause forbids the government from establishing an official religion, from giving preference to a specific religion and from giving favor to or disfavoring religion in general.

Officials at one of the schools, Cambridge Christian, filed suit, arguing that banning the prayer violated its right to free speech and to the free exercise of religion. Lower courts entered orders in the association’s favor, but attorneys for the school petitioned the Supreme Court to hear the case.

As a faculty member who teaches and researches law relating to religion and education, I believe the justices are likely to take the case – and that its outcome could be consequential. I say this because the Supreme Court’s recent record in First Amendment cases has been more friendly to religious plaintiffs than ever in its history.

A police officer with his back to the camera stands outside the Supreme Court. — The Supreme Court is expected to announce this fall whether it will hear Cambridge Christian’s case.
AP Photo/Mariam Zuhaib

Government speech

Following multiple rounds of litigation, Cambridge Christian School v. Florida High School Athletic Association reached a federal appeals court in September 2024. The 11th Circuit unanimously affirmed an order upholding the association’s policy not to allow prayer over the public address system.

The 11th Circuit based its findings in its view that prayer would be a form of “government speech”: that it would be perceived as representing the state association, not just the Christian schools. While the First Amendment limits the government’s ability to regulate private speech, the government is free to regulate its own speech.

Therefore, the court held that association officials did not violate the school’s right to free speech or free exercise of religion.

In part, the 11th Circuit relied on a similar Supreme Court case from 2000, which also examined prayer at a high school football game: Santa Fe Independent School District v. Doe.

In the Santa Fe ruling, the justices invalidated a board’s policy of allowing prayer over the public-address system “by a speaker representing the student body, under the supervision of school faculty.” Such a policy violated the First Amendment’s establishment clause, they determined, because “an objective Santa Fe High School student will unquestionably perceive the inevitable pregame prayer as stamped with her school’s seal of approval.”

Endorsement test

According to reasoning known as the “endorsement test,” a message violates the establishment clause if someone listening would reasonably assume that the government is endorsing religion. This test originated in Lynch v. Donnelly, a 1984 dispute over a public Christmas display in a Rhode Island park owned by a nonprofit.

Recently, however, the Supreme Court explicitly rejected the endorsement test – potentially strengthening Cambridge Christian’s case. The court rejected it and a similar set of criteria, called the “Lemon test,” in another football-related case, 2022’s Kennedy v. Bremerton School District.

The majority opinion upheld the right of a football coach in a public high school, Joseph Kennedy, to pray silently on the field at the end of games. The justices explained that the establishment clause does not “require the government to single out private religious speech for special disfavor,” adding that the court “long ago abandoned Lemon and its endorsement test offshoot.”

A man with silver hair who is wearing a short-sleeved blue polo stands before microphones, as a half-dozen people stand around him. — Former assistant football coach Joseph Kennedy after his case, Kennedy vs. Bremerton School District, was argued before the Supreme Court on April 25, 2022.
Win McNamee/Getty Images

The Lemon test“ was the standard the Supreme Court had used since 1971 to evaluate interactions between the government and religion. Under Lemon, there were three key criteria for whether a law or government speech violated the establishment clause. To be permitted, a governmental action must have a secular purpose, and its main effect cannot either advance or inhibit religion. Lastly, the action “must not foster ‘an excessive government entanglement with religion.‘”

In Bremerton, repudiating Lemon, the justices declared that courts should instead assess establishment clause claims based on “historical practices and understandings.”

If the Supreme Court agrees to hear Cambridge Christian’s appeal, the justices will face two issues. The first is whether communal prayer over a loudspeaker before a state athletic association game is indeed government speech – especially because officials permitted a wide array of nonreligious private speech over the loudspeaker. The second issue is whether the endorsement factor of the government-speech doctrine revives the endorsement test.

Recent record

If the justices agree to hear Cambridge Christian, it must be viewed against the court’s recent history in disputes over religion. The majority has often been friendly toward religious plaintiffs in cases under both religion clauses of the Constitution: establishment and free exercise.

In recent years, for example, the justices allowed aid to faith-based school students, found that a board could not prevent Kennedy from praying silently on the field after games, and granted employees time off to worship.

Two important issues remain to be seen: first, whether the justices will continue expanding the boundaries of religious freedom; and second, whether Cambridge Christian will generate such a result.

Regardless of how the Supreme Court rules – and whether it does rule – Florida has already adopted a law requiring athletic associations to allow participating high schools “to make brief opening remarks, if requested … using the public address system at the event.”

Come fall 2025, the Supreme Court will decide whether to hear the case. If so, its judgment may clarify whether private speech using public PA systems becomes governmental speech. Because the 11th Circuit relied on the endorsement test that the Supreme Court expressly repudiated, it seems likely that the justices will hear the appeal and rule in Cambridge Christian’s favor.

If the court does agree to review Cambridge Christian, it may well expand the parameters of religious expression in public – not just at football games.

Charles J. Russo does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. Football and faith could return to the Supreme Court – this time, over loudspeakers – https://theconversation.com/football-and-faith-could-return-to-the-supreme-court-this-time-over-loudspeakers-262104

August 5, 2025

Des primes d’assurance personnalisées moins chères grâce à l’IA ? Voici pourquoi il s’agit d’une pente glissante

Source: The Conversation – in French – By Arthur Charpentier, Professeur, Université de Rennes 1 – Université de Rennes

L’assurance repose sur un principe de solidarité que mettent à mal les algorithmes chargés de constituer nos profils. À mesure en effet que les algorithmes se précisent, la facture se personnalise. Divers profils « à risque » peuvent ainsi se retrouver exclus des régimes d’assurance, tant les coûts sont élevés. La personnalisation a une légitimité évidente. On doit toutefois lui concilier un accès équitable à l’assurance.

Il faut d’abord savoir que l’assurance est traversée par un paradoxe fondamental. D’un côté, ses principes mêmes supposent un mécanisme collectif où chacun contribue selon sa capacité, et tire profit de la solidarité en cas de sinistre. De l’autre, les avancées technologiques, les données de plus en plus massives et les méthodes actuarielles de plus en plus précises poussent à individualiser toujours davantage les tarifs.

À cette tension s’ajoute un cadre légal de plus en plus exigeant, qui interdit toute forme de discrimination fondée sur des données sensibles, parfois corrélées à des facteurs de risque pourtant pertinents.

Professeur de mathématiques à l’Université du Québec à Montréal (UQAM), je suis co-auteur du Manuel d’Assurance et auteur récent de l’ouvrage Insurance, Biases, Discrimination and Fairness. Cet article revient sur la difficulté de concilier la mutualisation solidaire, qui fonde l’assurance, avec l’hypersegmentation tarifaire rendue possible par les mégadonnées, sans exclure ni discriminer les assurés.

Déjà des milliers d’abonnés à l’infolettre de La Conversation. Et vous ? Abonnez-vous gratuitement à notre infolettre pour mieux comprendre les grands enjeux contemporains.

La segmentation tarifaire

Les compagnies d’assurance utilisent depuis longtemps la classification comme pilier de leur modèle économique : âge, sexe, profession, zone géographique, historique de sinistralité…

En 1662, le statisticien anglais John Graunt publie les Bills of Mortality, une première analyse statistique des registres de décès de Londres. En 1693, l’astronome anglais Edmund Halley élabore la première table de mortalité chiffrée, qui permet de calculer l’espérance de vie à chaque âge. Ces travaux posent les bases d’une tarification différenciée selon l’âge et le sexe, longtemps restés les deux grands critères de segmentation en vie-décès.

À la même époque, après le Grand Incendie de Londres en 1666, les premiers contrats d’assurance incendie apparaissent : les compagnies collectent des données sur la nature des matériaux de construction et la densité urbaine. Aux XVIIIe–XIX^e siècles, on segmente les tarifs selon la proximité des bâtiments voisins et la présence de services de lutte contre l’incendie, donnant naissance aux premières « zones à haut risque » et « zones à faible risque ».

Avec l’essor de l’automobile dans les années 1910–1920, les assureurs américains commencent à relever systématiquement le nombre de sinistres, l’âge et le sexe des conducteurs. Dès les années 1920, on distingue plusieurs « classes » tarifaires : jeunes conducteurs, conductrices, conducteurs expérimentés, permettant de fixer des primes variables en fonction du profil.

Aujourd’hui, les actuaires disposent d’algorithmes sophistiqués, d’outils de machine learning et d’une avalanche de données : télématique embarquée, objets connectés, géolocalisation, comportement de conduite ou de vie… Pour l’assureur, affiner la segmentation lui permet de facturer chaque assuré « à son vrai niveau de risque », en réduisant les effets de subvention croisée des bons risques vers les mauvais, tout en améliorant la rentabilité globale.

Mais une tarification trop fine réduit la mutualisation ; elle peut rendre l’assurance très coûteuse, voire inaccessible pour certains segments à haut risque. Aussi, aujourd’hui, l’actuaire cherche un équilibre subtil, visant à capter les bonnes informations pour différencier les profils, tout en préservant la viabilité de la communauté assurée.

Les assurés et l’illusion de la personnalisation gagnante

En Europe, la proposition législative FIDA (Financial Data Access Framework) ouvrirait aux assureurs un accès encadré aux données financières des particuliers. Son but est d’affiner la connaissance des comportements de dépense et de remboursement. Dans ce contexte, la promesse d’une tarification ultra-personnalisée suscite autant d’espoirs de baisse de primes que de craintes de profilage excessif, et d’exclusions importantes.

Face à ce nouvel afflux de données, de nombreux clients perçoivent la personnalisation comme une approche gagnant‑gagnant : si je gère mieux mon budget, je bénéficierai d’une ristourne ; si mes habitudes d’épargne et de remboursement sont jugées vertueuses, ma prime santé diminuera ; si mon profil financier se bonifie, mon assurance habitation se fera plus légère.

Cette logique de « pay‑as‑you‑live » ou « pay‑how‑you‑drive » séduit : l’individu se pense maître de son coût d’assurance par ses choix de vie.

Pourtant, plusieurs points méritent d’être soulignés.

Le principe de mutualisation n’est pas neutralisé : ceux qui ne peuvent pas adopter les comportements les plus vertueux restent dépendants de la solidarité des autres. En effet, même si les personnes les plus à risque paient davantage à titre individuel, celles qui sont moins à risque continuent néanmoins de supporter une part des coûts grâce au principe de mutualisation.
L’asymétrie d’information se renforce, l’assureur connaissant mieux les statistiques que le client. L’offre de personnalisation s’appuie en effet souvent sur des corrélations, parfois ténues, dont le client ignore la portée.
Une personnalisation très fine peut contraindre les plus à risque à se surassurer, ou au contraire à renoncer à s’assurer, fragilisant la mutualité.

Ainsi, même renforcée par l’accès aux données financières, la « personnalisation » n’est pas nécessairement synonyme d’ « empowerment » pour le consommateur.

Le cadre légal : quand la lutte contre la discrimination s’impose

Le développement des données massives en assurance soulève d’importantes questions éthiques et juridiques : jusqu’où peut‑on exploiter des variables sensibles pour prédire le risque ?

En France et dans l’Union européenne, la législation interdit explicitement la discrimination fondée sur des critères protégés : origine ethnique, genre, orientation sexuelle, handicap, convictions religieuses, etc. La Directive Solvabilité II (UE) impose aux assureurs d’utiliser des modèles de risque « transparents » et non discriminatoires.

Contrairement à l’Union européenne – qui bannit la tarification différenciée selon des critères protégés (genre, origine, handicap) –, le modèle québécois offre un cadre encore permissif. Si la Charte des droits et libertés de la personne du Québec interdit également la discrimination, elle prévoit des exemptions propres aux assureurs : ceux-ci peuvent, lorsqu’un facteur est statistiquement pertinent, fonder la tarification sur l’âge, le sexe ou l’état civil.

Cet usage, autorisé sur la seule base d’une corrélation, soulève des questions.

Éthique et responsabilité sociale des assureurs

Au‑delà de la seule conformité juridique, les assureurs sont de plus en plus jugés sur leurs pratiques éthiques et leur responsabilité sociale par des associations de consommateurs et les médias, qui relaient les incidents de discrimination algorithmique et exercent une pression de réputation.

Depuis quelques années, les assureurs doivent donc se demander, collectivement, comment garantir un accès équitable à leurs produits pour les populations vulnérables, sans sacrifier la viabilité financière de leurs portefeuilles. Certains modèles novateurs proposent des formules « solidaires » ou des tarifs plafonnés pour éviter l’exclusion.

Les assureurs se voient imposer sans cesse plus de transparence. Ils doivent expliquer de façon claire les critères tarifaires, rendre accessibles les clefs de calcul pour éviter le sentiment d’arbitraire. Enfin, ils doivent intégrer la protection des données et la vie privée dès la conception des offres ( « privacy by design »), préserver la confiance.

Les assureurs qui sauront concilier personnalisation, équité et inclusion deviendront les acteurs de référence pour les clients soucieux d’éthique.

Réconcilier solidarité et données : un défi crucial

Le défi, on le voit, est de taille.

Il s’agit ni plus ni moins de réconcilier la finesse actuarielle avec les valeurs de redistribution et de solidarité qui ont fondé le métier d’assureur.

C’est dans cette tension résolue que se jouera l’avenir de l’assurance : ni pure discrimination tarifaire ni simple personnalisation illusoire, elle les conjuguera plutôt en un équilibre permettant à chacun de contribuer selon son risque et de bénéficier à sa juste mesure de la mutualisation des aléas de la vie.

Arthur Charpentier est membre (fellow) de l’Institut Louis Bachelier. Il a reçu des financements du CRSNG (NSERC) de 2019 à 2025, du Fond AXA Pour la Recherche de 2020 à 2022, puis de la Fondation SCOR pour la Science de 2023 à 2026.

– ref. Des primes d’assurance personnalisées moins chères grâce à l’IA ? Voici pourquoi il s’agit d’une pente glissante – https://theconversation.com/des-primes-dassurance-personnalisees-moins-cheres-grace-a-lia-voici-pourquoi-il-sagit-dune-pente-glissante-259861

August 5, 2025

Donald Trump limoge la cheffe des statistiques sur le travail et affaiblit les bases des politiques sociales

Source: The Conversation – in French – By Sarah James, Assistant Professor of Political Science, Gonzaga University

Les programmes gouvernementaux sont-ils efficaces ? Impossible de le savoir sans données. Andranik Hakobyan/iStock/GettyImagesPlus

En freinant la production de données officielles, l’administration Trump met en péril la transparence et l’avenir des politiques sociales aux États-Unis.

Le 1^er août 2025, le président Donald Trump a limogé la commissaire du Bureau de la statistique du travail (Bureau of Labor Statistics ou BLS) Erika McEntarfer, après la publication d’un rapport défavorable sur le chômage. Cette décision a suscité de vives critiques en raison du risque qu’elle sape la crédibilité de l’agence. Mais ce n’est pas la première fois que l’administration Trump prend des mesures susceptibles d’affaiblir l’intégrité de certaines données gouvernementales.

Prenons l’exemple du suivi de la mortalité maternelle aux États-Unis, qui est la plus élevée parmi les pays développés. Depuis 1987, les centres pour le contrôle et la prévention des maladies (Centers for Disease Control and Prevention) administrent le système de surveillance de l’évaluation des risques liés à la grossesse afin de mieux comprendre quand, où et pourquoi ces décès surviennent. En avril 2025, l’administration Trump a placé ce département, chargé de la collecte et du suivi de ces données, en congés forcés.

Pour l’instant, rien n’indique que des données du BLS ont été supprimées ou altérées. Mais des rapports font état de situations similaires dans d’autres agences.

La Maison-Blanche collecte également moins d’informations, qu’il s’agisse de savoir combien d’Américains disposent d’une assurance maladie ou du nombre d’élèves inscrits dans les écoles publiques, et elle rend inaccessibles au public de nombreuses données gouvernementales. Donald Trump tente également de supprimer des agences entières, comme le département de l’éducation, qui sont responsables de la collecte de données cruciales liées à la pauvreté et aux inégalités. Son administration a aussi commencé à supprimer des sites web et des répertoires qui partagent les données gouvernementales avec le public.

Pourquoi les données sont essentielles pour le filet de sécurité

J’étudie le rôle que jouent les données dans la prise de décision politique, y compris quand et comment les responsables gouvernementaux décident de les collecter. Au fil de plusieurs années de recherche, j’ai constaté que de bonnes données sont essentielles non seulement pour les responsables politiques, mais aussi pour les journalistes, les militants ou les électeurs. Sans elles, il est beaucoup plus difficile de déterminer quand une politique échoue et encore plus compliqué d’aider les personnes qui ne sont pas dans les radars et qui n’ont pas de connexions politiques.

Depuis que Trump a prêté serment pour son second mandat, je surveille de près les conséquences de la perturbation, de la suppression et du sous-financement des données sur les programmes de filet de sécurité sociale, comme l’aide alimentaire ou les services destinés aux personnes en situation de handicap.

J’estime que perturber la collecte de données rendra plus difficile l’identification des personnes éligibles à ces programmes ou la compréhension de ce qui se passe lorsque des bénéficiaires perdent leur aide. Je crois aussi que l’absence de ces données compliquera considérablement le travail des défenseurs de ces programmes sociaux pour les reconstruire à l’avenir.

Pourquoi le gouvernement collecte ces données

Il est impossible de savoir si des politiques et programmes fonctionnent, sans données fiables collectées sur une longue période. Par exemple, sans un système permettant de mesurer avec précision combien de personnes ont besoin d’aide pour se nourrir, il est difficile de déterminer combien le pays doit consacrer au Supplemental Nutrition Assistance Program (le programme alimentaire fédéral), au programme fédéral d’aide nutritionnelle (connu sous le nom de WIC) destiné aux femmes, nourrissons et enfants, ainsi qu’aux programmes associés.

Les données sur l’éligibilité et l’inscription à Medicaid avant et après l’adoption de l’Affordable Care Act (ACA) en 2010 en sont un autre exemple. Les données nationales ont montré que des millions d’Américains ont obtenu une couverture santé après la mise en œuvre de l’ACA.

De nombreuses institutions et organisations, comme les universités, les médias, les think tanks et les associations à but non lucratif qui se concentrent sur des enjeux tels que la pauvreté et les inégalités ou le logement, collectent elles aussi des données sur l’impact des politiques sociales sur les Américains à faible revenu.

Il ne fait aucun doute que ces efforts non gouvernementaux vont se poursuivre, voire s’intensifier. Cependant, il est très improbable que ces initiatives indépendantes puissent remplacer les programmes de collecte de données du gouvernement – encore moins l’ensemble d’entre eux. Parce qu’il met en œuvre les politiques officielles, le gouvernement est dans une position unique pour collecter et pour conserver des données sensibles sur de longues périodes. C’est pourquoi la disparition de milliers de sites web officiels peut avoir des conséquences à très long terme.

Ce qui distingue l’approche de Trump

La mise en pause, la réduction de financement et la suppression des données gouvernementales par l’administration Trump marquent une rupture majeure avec ses prédécesseurs.

Dès les années 1930, les chercheurs en sciences sociales et les responsables politiques locaux américains avaient compris le potentiel des données pour identifier quelles politiques étaient efficaces et lesquelles représentaient un gaspillage d’argent. Depuis lors, les responsables politiques de tout l’éventail idéologique se sont de plus en plus intéressés à l’utilisation des données pour améliorer le fonctionnement de l’État.

Cet intérêt pour les données s’est accentué à partir de 2001, lorsque le président George W. Bush a fait de la responsabilisation du gouvernement sur la base de résultats mesurables une priorité. Il considérait les données comme un outil puissant pour réduire le gaspillage et évaluer les résultats des politiques publiques. Sa réforme phare en matière d’éducation, le No Child Left Behind Act, a profondément élargi la collecte et la publication de données sur les performances des élèves dans les écoles publiques de la maternelle à la terminale.

En quoi cela contraste avec les administrations Obama et Biden

Les présidents Barack Obama et Joe Biden ont mis l’accent sur l’importance des données pour évaluer l’impact de leurs politiques sur les populations à faible revenu, historiquement peu influentes sur le plan politique. Obama a mis en place un groupe de travail chargé d’identifier des moyens de collecter, analyser et intégrer davantage de données utiles dans les politiques sociales.

Biden a mis en œuvre plusieurs des recommandations de ce groupe. Par exemple, il a exigé la collecte et l’analyse de données démographiques pour évaluer les impacts des nouvelles politiques sociales. Cette approche a influencé la manière dont son administration a géré les changements dans les pratiques de prêts immobiliers, l’expansion de l’accès au haut débit et la mise en place de programmes de sensibilisation pour inscrire les citoyens à Medicaid et Medicare.

Pourquoi il sera difficile de reconstruire

Il est plus difficile de défendre l’existence de programmes sociaux lorsqu’il n’existe pas de données pertinentes. Par exemple, des programmes qui aident les personnes à faible revenu à consulter un médecin, à avoir accès à des produits frais ou à trouver un logement peuvent être plus rentables que de simplement laisser les gens vivre dans la pauvreté.

Bloquer la collecte de données peut aussi compliquer le rétablissement du financement public après la suppression ou l’arrêt d’un programme. En effet, il sera alors plus difficile pour les anciens bénéficiaires de ces programmes de convaincre leurs concitoyens qu’il est nécessaire d’investir dans l’extension d’un programme existant ou dans la création d’un nouveau.

Faute de données suffisantes, même des politiques bien intentionnées risquent à l’avenir d’aggraver les problèmes qu’elles sont censées résoudre, et ce, bien après la fin de l’administration Trump.

Sarah James ne travaille pas, ne conseille pas, ne possède pas de parts, ne reçoit pas de fonds d’une organisation qui pourrait tirer profit de cet article, et n’a déclaré aucune autre affiliation que son organisme de recherche.

– ref. Donald Trump limoge la cheffe des statistiques sur le travail et affaiblit les bases des politiques sociales – https://theconversation.com/donald-trump-limoge-la-cheffe-des-statistiques-sur-le-travail-et-affaiblit-les-bases-des-politiques-sociales-262632

August 5, 2025

Suplemento cultural: nuestra vida desde Jesse y Céline

Source: The Conversation – (in Spanish) – By Claudia Lorenzo Rubiera, Editora de Cultura, The Conversation

Julie Delpy e Ethan Hawke en ‘Antes del amanecer’. IMDB

Este texto se publicó por primera vez en nuestro boletín Suplemento cultural, un resumen quincenal de la actualidad cultural y una selección de los mejores artículos de historia, literatura, cine, arte o música. Si quiere recibirlo, puede suscribirse aquí.

Mi madre me llevó en 1995, hace 30 años, a los Minicines de Oviedo a ver Antes del amanecer. Yo tenía 9 años y me pareció un castañazo épico. “No se callaban”, le eché en cara cuando salimos. No tardé mucho, probablemente un lustro, en reconciliarme con la película y rendirme al encanto de la historia de amor de Jesse y Céline, trenzada a base de conversaciones.

Esta semana, tras editar el estupendo artículo de Celestino Deleyto y Marimar Azcona, volví a revisitarla y me quedé atrapada en un comentario que hace Jesse en los primeros minutos de la película. Cuando Céline le pregunta qué tal le está yendo en ese viaje a través de Europa en el que está inmerso, dice algo como que ha sido un asco pero que “estar sentado en un tren mirando por la ventana durante dos semanas le ha dado para pensar ideas que no se le hubiesen ocurrido de otra forma”. Esa frase me produjo escalofríos porque primero pensé “¿hace cuánto que no viajo en tren durante horas solo mirando por la ventana?” y eso me llevó al segundo razonamiento: “¿cuántas cosas interesantes no estoy pensando porque no le estoy dejando espacio al cerebro?”

De repente, Antes del amanecer, un relato precioso que idealizaba el enamoramiento joven, la magia de la conexión y el encanto de una vieja ciudad europea, se revelaba como una narración, hoy en día, mucho más cercana a la ciencia ficción que, por ejemplo, el Minority Report de Steven Spielberg.

Cómo ha cambiado el mundo… a pesar de que los seres humanos seguimos siendo los mismos.

To ChatGPT or not to ChatGPT?

El filósofo germano-coreano Byung-Chul Han ha sido galardonado con el Premio Princesa de Asturias de Comunicación y Humanidades. Su figura enciende debates entre quienes aprecian su cercanía a la gente y su claridad expositiva y aquellos que creen que, en esencia, utiliza pocas palabras para decir… también poco.

Jesús Zamora Bonilla es uno de los críticos con el personaje, un punto de vista que expuso en un artículo académico. Cuando le propusimos sintetizar sus tesis hizo algo poco ortodoxo y muy macarra que ha acabado resultando ser desternillante: le preguntó a ChatGPT cuáles son las principales críticas que se le hacen a Han. Cuando vio que la respuesta era, prácticamente, la misma que la suya y que estaba bien argumentada decidió mantener el texto hecho por la inteligencia artificial alegando que si el filósofo no hacía más que meterse con la IA, la IA debía tener derecho de réplica.

El artículo coincidió en el tiempo con otro, de Ronald Forero-Álvarez, en el que el investigador debatía si, al utilizar a ChatGPT para escribir un libro, la autoría debía compartirse entre el ideólogo y la máquina, y se preguntaba quién tenía que rendir cuentas en esos casos: el humano o la tecnología. En nuestro caso podemos decir que Zamora Bonilla es el responsable de su texto y que no le hemos pedido a ChatGPT que rellene una ficha de autor.

Merece la pena leer ambos artículos, tan lejanos a la Viena de Antes del amanecer, y plantearse preguntas exclusivas del mundo de hoy.

Peter Hujar y la primera imagen del Orgullo

Hace unos años leí un libro titulado Los optimistas, escrito por Rebecca Makkai, que narraba los primeros tiempos del sida en Estados Unidos (en concreto, en Chicago). La cubierta del libro era la foto (que está sobre estas líneas) de unos jóvenes que parecían manifestarse en medio de la calle de una ciudad. Sonreían, por lo que imaginé que iba acorde con el optimismo del título.

Después supe, gracias a Arte compacto y su imprescindible pódcast sobre la historia del arte, que la foto era obra de Peter Hujar.

Y finalmente Noemí Díaz Rodríguez escribió un estupendo artículo sobre esta imagen, creada para ilustrar el cartel que buscaba reclutar a gente para unirse a la que se convertiría, en 1970, en la primera marcha del Orgullo celebrada en Nueva York.

Cajón desastre

Después del susto que nos dio a finales de 2024, Raphael ha retomado su gira española. Estrella Fernández-Jiménez explica por qué, si cerramos los ojos y pensamos en el cantante, además de verle entonar seremos capaces de recrear en nuestra mente unos gestos que son solo suyos y que ha ido trabajando a lo largo de su carrera.

No tuvo una acogida tan popular, pero unos años después de Shakespeare enamorado se estrenó una película titulada Belleza prohibida, que narraba la revolución que supuso en el teatro inglés que las mujeres pudiesen volver a subirse a los escenarios.

Y esa época describe precisamente Laura Martínez García en su artículo, centrándose en lo revolucionario que fue que, de repente, en una sociedad tremendamente segregada, las actrices y dramaturgas pudiesen ocupar el espacio público.

Y para acabar cerrando el círculo, volvamos a los 90. Entre mi visita a los Minicines y este 20 de junio la comedia en España ha pasado de venderse en formatos como No te rías que es peor a promocionar los monólogos de Ignatius Farray o, hablando de ocupar el espacio público, a lanzar late nights presentados por mujeres como Henar Álvarez.

Si eso ha pasado en 30 años, ¡qué no habrá pasado en 120! De recopilar, documentar y analizar la historia del humor oral en España desde principios del siglo XXI se encargará a partir de ahora Humcor, el primer archivo digital dedicado a esta especialidad en el país. Doina Repede, su directora, aprovecha para explicar cómo hemos cambiado en esto de reírnos.

– ref. Suplemento cultural: nuestra vida desde Jesse y Céline – https://theconversation.com/suplemento-cultural-nuestra-vida-desde-jesse-y-celine-262532

August 5, 2025

Why do some clothes shrink in the wash? A textile scientist explains how to ‘unshrink’ them

Source: The Conversation – Global Perspectives – By Nisa Salim, Director, Swinburne-CSIRO National Testlab for Composite Additive Manufacturing, Swinburne University of Technology

When your favourite dress or shirt shrinks in the wash, it can be devastating, especially if you followed the instructions closely. Unfortunately, some fabrics just seem to be more prone to shrinking than others – but why?

Understanding more about the science of textile fibres can not only help you prevent the shrinkage of clothing, but also might help you “rescue” the occasional garment after a laundry accident.

It’s all down to the fibres

To know more about clothing shrinkage, we first need to understand a little about how textiles are made.

Common textile fibres, such as cotton and linen, are made from plants. These fibres are irregular and crinkled in their natural form. If you zoom deeper inside them, you’ll see millions of tiny, long-chain cellulose molecules that naturally exist in coiled or convoluted shapes.

Extreme close-up of a sewing thread shows the individual fibres, made up of millions of invisible convoluted cellulose molecules.
Hadrian/Shutterstock

During textile manufacturing, these fibres are mechanically pulled, stretched and twisted to straighten and align these cellulose chains together. This creates smooth, long threads.

On a chemical level, there are also links between the chains called hydrogen bonds. These strengthen the fibre and the thread and make it more cohesive.

Threads are woven or knitted into fabrics, which locks in the tension that holds those fibres side by side.

However, these fibres have good “memory”. Whenever they’re exposed to heat, moisture or mechanical action (such as agitation in your washing machine), they tend to relax and return to their original crinkled state.

This fibre memory is why some fabrics wrinkle so easily and why some of them may even shrink after washing.

Cotton fabric under 40x magnification, showing the threads ‘locked’ in against each other.
Kateryna Kon/Shutterstock

How does washing shrink the fabric?

To understand shrinkage, we again need to zoom down to the molecular level. During laundering, hot water helps to increase the energy level of fibres – this means they shake more rapidly which disrupts the hydrogen bonds holding them in place.

The way a fabric is knitted or woven also plays a role. Loosely knitted fabrics have more open spaces and loops, making them more susceptible to shrinkage. Tightly woven fabrics are more resistant because the threads are locked into place with less room to move.

Additionally, cellulose is hydrophilic – it attracts water. Water molecules penetrate inside the fibres, causing swelling and making them more flexible and mobile. Adding to all this is the tumble and twist action inside the washing machine.

The whole process makes the fibres relax and recoil back to their natural, less stretched, crinkled state. As a result, the garment shrinks.

It’s not just hot water – here’s why

This doesn’t just happen with hot water, as you may have experienced yourself with clothes made of rayon, for example.

Cold water can still penetrate into fibres, making them swell, along with the mechanical action of the tumbling in the washing machine. The effect is less dramatic with cold water, but it can happen.

To minimise shrinkage, you may use cold water, the lowest spin speed or the gentlest cycle available, especially for cotton and rayon. Machine labels don’t always fully explain the impact of spin speed and agitation. When in doubt, choose a “delicate” setting.

What about wool?

Different fibres shrink in different ways; there is no single mechanism that fits all.

While cellulose-based fabrics shrink as described above, wool is an animal-derived fibre made of keratin proteins. Its surface is covered in tiny, overlapping scales called cuticle cells.

Wool fibre under a microscope with the cuticles visible as overlapping scales.
snap the reel/Shutterstock

During washing, these cuticles open up and interlock with neighbouring fibres causing fibre entanglement or “felting”. This makes the clothing feel denser and smaller – in other words, it shrinks.

Why don’t synthetics shrink as much?

Synthetic fibres such as polyester or nylon are made from petroleum-based polymers, engineered for stability and durability.

These polymers contain more crystalline regions that are highly ordered and act as an internal “skeleton”, preventing the fibres from crinkling.

The weave of nylon stockings under a microscope shows how the threads are much smoother and more crystalline than natural fibres.
Alexander Klepnev/Wikimedia Commons, CC BY

Textile scientists and engineers are also working on fabrics that resist shrinkage through advanced material design. Among promising innovations are blended yarns that combine natural and synthetic fibres.

Some researchers are working on shape-memory polymers that can change shape – or return to a previous shape – in response to temperature or water, for example. This is different to stretch fabrics (such as those used in activewear) that are made up of highly elastic fibres which “bounce back” to their original state after stretching.

How can I unshrink a piece of clothing?

If a favourite garment has shrunk in the wash, you can try to rescue it with this simple method.

Gently soak the item in lukewarm water mixed with hair conditioner or baby shampoo (approximately one tablespoon per litre). Then, carefully stretch the fabric back into shape and dry it flat or under gentle tension – for example, by pegging the garment to a drying rack.

The reason this works is because conditioners have chemicals known as cationic surfactants. These will temporarily lubricate the fibres, making them more flexible and allowing you to gently pull everything back into place.

This process can’t completely reverse extreme shrinkage but it can help recover some of the lost size, making the clothes wearable again.

Nisa Salim does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. Why do some clothes shrink in the wash? A textile scientist explains how to ‘unshrink’ them – https://theconversation.com/why-do-some-clothes-shrink-in-the-wash-a-textile-scientist-explains-how-to-unshrink-them-259388

August 5, 2025

How do you feel about doing exams? Our research unearthed 4 types of test-takers

Source: The Conversation – Global Perspectives – By Andrew J. Martin, Scientia Professor and Professor of Educational Psychology, UNSW Sydney

If you had to do a test, how would you respond? Would you relish the chance to demonstrate your knowledge? Or worry you were about to fall short of the mark and embarrass yourself?

Research tells us students’ attitudes towards taking tests or doing exams can have an impact on their performance. This is because what they think about themselves, the test questions, and the consequences of the test can impact their motivation and focus during the test.

To date, this research has largely grouped students into two main types of test-takers. One group sees tests as a challenge they can cope with. Another sees tests as a threat they will not be able to handle.

But some studies have suggested these groupings may be too broad to give useful support to students.

In our new study, the largest of its kind, we explored Australian high school students taking a science test. By capturing diverse psychological data, such as students’ brainwaves and stress responses, we found there are four types of test-takers.

Our study

We studied 244 male and female students from three Sydney schools in years 8 to 10 as they did a science test.

It is the largest study of its kind to collate diverse information on students’ brain wave activity, physiological responses and self-reported attitudes while they are doing a test.

This is significant because this kind of research is usually done in labs with large functional magnetic resonance imaging (fMRI) machines, a setting quite different from a real classroom. Our approach allowed us to get a well-rounded look at the different psychological indicators at play when students do a test.

The students were part of a larger research project looking at science engagement. The test was developed by our research team, with guidance from science teachers.

How we set up our research

Students wore an electroencephalogram (EEG) headset during the test to capture their brain activity, via alpha and theta waves.

The alpha waves measured how much students were focusing on the test and the theta waves looked at the strain on their working memory (which students need to use to solve problems in a test). Both these capacities can be disrupted if a person feels threatened or stressed.

Students also wore a biometric wristband that measured their sweat glands. In our study, lower “electrodermal activity” scores indicated a calmer and more positive state, and higher scores indicated stress.

Midway through the test, students reported how confident they were about meeting the demands of the test and how anxious they felt about not meeting the demands.

We then used a statistical technique called latent profile analysis to help us identify different types of test-takers. This technique enables researchers to identify subgroups based on certain variables.

4 types of test-takers

We were able to identify four groups of students who had distinct patterns on these different measures.

1. Confident striders: these students took the test “in their stride”. They reported high confidence and low anxiety, and recorded an optimal balance of attention and working memory. Their wristband readings indicated they were calm. They made up 27% of the group.

2. Confident battlers: also reported they were confident and low in anxiety, but other data suggested they were battling behind the scenes. Their wristband readings suggested their “fight or flight” system was aroused. Their brain waves also showed their working memory did not have as much capacity to problem-solve as the confident striders, which also indicates a level of stress. They made up 8% of the group.

3. Ambivalents: these students were average across all of the indicators, reflecting that they didn’t see the test as a challenge or a threat. They made up 38% of the group.

4. Fearers: reported low confidence and high anxiety. Their wristband readings indicated they were stressed, and their brain wave readings showed they were not directing much direction to the actual test. They made up 27% of the group.

How did these test-takers perform on the test?

We then looked at the test performance for each of these four test-takers. Not surprisingly, confident striders were the highest achievers. Confident battlers also did well on the test, but not as well as striders. Ambivalents scored lower on the test, but not as low as fearers.

These results were measured against students’ previous science results (in school tests and assignments), because we wanted to know whether students performed above or below their usual level. This was to ensure we were measuring the impact of students’ psychological approach to the test, rather than just how good they are at science.

Taken together, our findings suggest that believing in themselves, confronting any fearful thoughts, and having a clear mind to concentrate on the task, puts students in the strongest position to perform well.

What can teachers do?

Our findings also provide guidance for teachers to target the factors that defined the test-takers.

To help build confidence, students can be taught how to challenge doubts about themselves. This can include reminding students of their strengths as they approach the test. For example, students could reflect on how well they conducted the experiments in their science lessons if the test includes questions about those experiments.
To ease anxiety, students can be taught constructive ways to think about challenging schoolwork. For example, students can remind themselves of the knowledge they have learned that will be helpful. Students can also be taught to use breathing and mindfulness exercises to ease stress. This can reduce a physical stress response and help focus their attention on the task at hand.
To optimise working memory, for in-class assessments teachers can match the test to students’ abilities and prior learning. This means the test is challenging enough, but not so overwhelming that it excessively burdens working memory while they are problem solving. This can also help build confidence ahead of other, higher-stakes exams.

Andrew J. Martin received funding from the Australian Research Council and The King’s School for this research. He also receives funding from Commonwealth and state departments of education.

Emma Burns receives funding from the Australian Research Council, is an associate editor for the Australian Educational Researcher and is on the board of the Australian Educational Research Organisation.

Joel Pearson receives funding from The Australian Research Council.

Rebecca J. Collie receives funding from Commonwealth and State Departments of Education. She has also received funding from the Australian Research Council.

Roger Kennett received funding from the Australian Research Council and The King’s School for this research.

– ref. How do you feel about doing exams? Our research unearthed 4 types of test-takers – https://theconversation.com/how-do-you-feel-about-doing-exams-our-research-unearthed-4-types-of-test-takers-261552

August 5, 2025

New Trump tariffs: early modelling shows most economies lose – the US more than many

Source: The Conversation – Global Perspectives – By Niven Winchester, Professor of Economics, Auckland University of Technology

The global rollercoaster ride of United States trade tariffs has now entered its latest phase.

President Donald Trump’s April 2 “Liberation Day” announcement placed
reciprocal tariffs on all countries. A week later, amid financial market turmoil, these tariffs were paused and replaced by a 10% baseline tariff on most goods.

On July 31, however, the Trump Administration reinstated and expanded the reciprocal tariff policy. Most of these updated tariffs are scheduled to take effect on August 7.

To evaluate the impact of these latest tariffs, we also need to take into account recently negotiated free trade agreements (such as the US-European Union deal), the 50% tariffs imposed on steel and aluminium imports, and tariff exemptions for imports of smartphones, computers and other electronics.

For selected countries, the reciprocal tariffs announced on April 2 and the revised values of these tariffs are shown in the table below. The revised additional tariffs are highest for Brazil (50%) and Switzerland (39%), and lowest for Australia and the United Kingdom (10%).

For most countries, the revised tariffs are lower than the original ones. But Brazil, Switzerland and New Zealand are subject to higher tariffs than those announced in April.

In addition to the tariffs displayed above, Canadian and Mexican goods not registered as compliant with the US-Mexico-Canada Agreement are subject to tariffs of 35% and 25% respectively.

Economic impacts

The economic impacts of the revised tariffs are examined using a global model of goods and services markets, covering production, trade and consumption.

A similar model was used to assess the impacts of the original reciprocal tariffs and the outcome of a US-China trade war.

GDP impacts of the tariffs are displayed in the table below. The impacts of the additional tariffs are evaluated relative to trade measures in place before Trump’s second term. Retaliatory tariffs are not considered in the analysis.

An economic own goal

The tariffs reduce US annual GDP by 0.36%. This equates to US$108.2 billion or $861 per household per year (all amounts in this article are in US dollars).

The change in US GDP is an aggregate of impacts involving several factors.

The tariffs will compel foreign producers to lower their prices. But these price decreases only partially offset the cost of the tariffs, so US consumers pay higher prices.

Businesses also pay more for parts and materials. Ultimately, these higher prices hurt the US economy.

The tariffs decrease US merchandise imports by $486.7 billion. But as they drive up the cost of US supply chains and shift more workers and resources into industries that compete with imports, away from other parts of the economy, they also decrease US merchandise exports by $451.1 billion.

Global impacts

For most other countries, the additional tariffs reduce GDP. Switzerland’s GDP decreases by 0.47%, equivalent to $1,215 per household per year. Proportional GDP decreases are also relatively large for Thailand (0.44%) and Taiwan (0.38%).

In dollar terms, GDP decreases are relatively large for China ($66.9 billion) and the European Union ($26.6 billion).

Australia and the United Kingdom gain from the tariffs ($0.1 billion and $0.07 billion respectively), primarily due to the relatively low tariffs levied on these countries.

Despite facing relatively low additional tariffs, New Zealand’s GDP decreases by 0.15% ($204 per household) as many of its agricultural exports compete with Australian commodities, which are subject to an even lower tariff.

Although the revised reciprocal tariffs are, on average, lower than those announced on April 2, they are still a substantial shock to the global trading system.

Financial markets have been buoyant since Trump paused reciprocal tariffs on April 9, partly on the hope that the tariffs would never be imposed. US tariffs of at least 10% to 15% now appear to be the new norm.

As US warehouses run down inventories and stockpiles, there could be a rocky road ahead.

Niven Winchester has previously received funding from the Productivity Commission and the Ministry of Foreign Affairs and Trade to estimate the impacts of potential trade policies. He is affiliated with Motu Economic & Public Policy Research.

– ref. New Trump tariffs: early modelling shows most economies lose – the US more than many – https://theconversation.com/new-trump-tariffs-early-modelling-shows-most-economies-lose-the-us-more-than-many-262491