We study minimax regret treatment rules under matched treatment assignment in a setup where a policymaker, informed by a sample of size N, needs to decide between T different treatments for a $T\geq 2$. Randomized rules are allowed for. We show that the generalization of the minimax regret rule derived in Schlag (2006, ELEVEN—Tests needed for a recommendation, EUI working paper) and Stoye (2009, Journal of Econometrics 151, 70–81) for the case $T=2$ is minimax regret for general finite $T>2$ and also that the proof structure via the Nash equilibrium and the “coarsening” approaches generalizes as well. We also show by example, that in the case of random assignment the generalization of the minimax rule in Stoye (2009, Journal of Econometrics 151, 70–81) to the case $T>2$ is not necessarily minimax regret and derive minimax regret rules for a few small sample cases, e.g., for $N=2$ when $T=3.$

In the case where a covariate x is included, it is shown that a minimax regret rule is obtained by using minimax regret rules in the “conditional-on-x” problem if the latter are obtained as Nash equilibria.

This study compares the design practices and performance of ChatGPT 4.0, a large language model (LLM), against graduate engineering students in a 48-h prototyping hackathon, based on a dataset comprising more than 100 prototypes. The LLM participated by instructing two participants who executed its instructions and provided objective feedback, generated ideas autonomously and made all design decisions without human intervention. The LLM exhibited similar prototyping practices to human participants and finished second among six teams, successfully designing and providing building instructions for functional prototypes. The LLM’s concept generation capabilities were particularly strong. However, the LLM prematurely abandoned promising concepts when facing minor difficulties, added unnecessary complexity to designs, and experienced design fixation. Communication between the LLM and participants was challenging due to vague or unclear descriptions, and the LLM had difficulty maintaining continuity and relevance in answers. Based on these findings, six recommendations for implementing an LLM like ChatGPT in the design process are proposed, including leveraging it for ideation, ensuring human oversight for key decisions, implementing iterative feedback loops, prompting it to consider alternatives, and assigning specific and manageable tasks at a subsystem level.

Agricultural monoculture negatively impacts soil quality, particularly in fragile soils that yield limited crop production and are highly susceptible to degradation. Increasing plant diversity in production systems can be an alternative for maintaining soil ecosystem services and increasing crop yields. This study investigated the influence of increased plant diversity on soil health and its impact on soybean and cotton yield in an Ultisol in the Brazilian savanna in Mato Grosso State, Brazil. Tested five levels of plant diversity after soybean harvest: 1) very low (VL), 2) low (LW), 3) average (AVG), 4) long term average (AVL) e 5) high (ICLS) were tested. Plant diversity improves the health of sandy loam soil, increases C and N fractions in particulate organic matter (POM-C and POM-N) and leads to differences in C utilization by the soil microbial community. High ICLS diversity raises total organic carbon levels (TC, being POM-C and POM-N, the labile fractions, more efficient to show changes in sandy loam soil, in the short term, over a period of three years. High diversity promoted yield gains of up to 251% for cotton and 82% for soybean in relation to very low plant diversity. Changes in soil microbial composition are able to partially explain crop yield in diversified production systems (R2 ranging from 0.51 to 0.80). Diversifying production components is a sustainable way to maintain biological functions and agricultural quality of loam sandy soil in the Brazilian Cerrado in Mato Grosso.

In this article, we investigate necessary and sufficient conditions on the perturbation ρ for the existence of positive least energy solutions of the critical singular semilinear elliptic equation $ -\Delta u = \frac{|u|^{2^{*}(s)-2}}{|x|^s}u + \rho(u) $ with Dirichlet boundary condition in a bounded smooth domain in $\mathbb R^n$ containing the origin, where $2^*(s)=\frac{2(n-s)}{n-2}$, $0\leq s \lt 2 \lt n$. We show that the almost necessary and sufficient condition obtained for the case s = 0 in [1] differs conceptually when $0 \lt s \lt 2$.

Brazilians in the United States voted overwhelmingly for right-wing populist Jair Bolsonaro in 2022. What role did religion play? Based on exit polling, focus groups, and observation of local Brazilian churches, this article explores how Christianity drives support for right-wing populism among Brazilian migrants to the Boston area. Christians, and especially evangelicals, are significantly more likely to vote for Bolsonaro, and the priests and pastors of Brazilian migrant churches are particularly willing to discuss parties and candidates. Yet neither clergy endorsements nor political conversations at church explain this religious effect. I argue that indirect influence within congregations, which reinforces a conservative worldview in non-overtly political ways, helps explain why most observant evangelicals favor Bolsonaro. Migrants potentially influence the voting behavior of friends and family in Brazil, including via transnational religious communities, so their political attitudes can help bolster authoritarian populism in the homeland, as also seen in India and Turkey.

Language control in the bilingual brain has remained in the limelight of research over the past decades. However, the mechanisms underlying bilingual language control may be more intricate than typically assumed due to the hierarchical nature of language. This study aimed to investigate the dynamics of bilingual language control at the phonetic level. Participants, who were speakers of Chinese, English and German, named the letters of the alphabet in English (L2) or German (L3) following an alternating language-switching paradigm. Two sets of letters were selected, differing in the phonological similarity of their pronunciation across the two languages, thereby allowing the exploration of cross-language phonological influences. Each participant completed two sessions of letter-naming tasks. In one session, seven phonologically similar letters were randomly repeated either in single-language blocks or in alternate-language blocks. In the other session, seven phonologically dissimilar letters were similarly manipulated. The results indicated local inhibition, reflected by switch costs and global inhibition, reflected by mixing costs. Reversed language dominance, another indicator of global inhibition, was not observed. However, there was a tendency for larger global inhibition to be applied to the more dominant language. Moreover, there was significantly faster naming for phonologically similar letters compared to dissimilar ones, suggesting a facilitation effect for both English and German, irrespective of whether letter naming occurred in single- or alternate-language blocks. These findings provided evidence for the role of inhibitory and facilitative mechanisms at the phonetic level, suggesting language-specific control in the bilingual brain and underscoring the complexity and dynamics of managing language control across multiple levels of processing.