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We prove that the vertices of every (r+1)$$ \left(r+1\right) $$‐uniform hypergraph with maximum degree Δ$$ \Delta $$ may be colored with cΔd+11/r$$ c{\left(\frac{\Delta}{d+1}\right)}^{1/r} $$ colors such that each vertex is in at most d$$ d $$ monochromatic edges. This result, which is best possible up to the value of the constant c$$ c $$, generalizes the classical result of Erdős and Lovász who proved the d=0$$ d=0 $$ case. [ABSTRACT FROM AUTHOR]

Although safety within operational systems depends on compliance with regulations, non-compliance is common in many settings. Trucking is a meaningful industry for studying operational safety compliance given that the industry is large and important, truck accidents kill thousands annually, and such accidents collectively cost the U.S. economy billions of dollars. Although the truck driving occupation is dominated by men, significant efforts are underway to recruit more women into the profession. If women are safer behind the wheel than men, increasing their ranks could improve overall safety compliance. Building on theory and evidence suggesting that men have a greater willingness to take risky actions and break rules, we used data on 22 million truck inspections from 2010 to 2022 to identify an operational safety compliance gap between men and women truckers. Overall, men were 7.4% more likely to be cited for a major violation of rules governing working hours (known as hours-of-service or HOS rules) and 13.2% more likely to have a major unsafe driving violation. We then examined whether gap changes based on carrier size and type. We found that the HOS compliance gap is smaller for small carriers (vs. large) and private carriers (vs. for-hire), but not the unsafe driving gap. Finally, we tested whether the introduction of an intervention—electronic logging devices (ELDs) that automatically record truckers' driving hours—closes the gap by increasing men's compliance. In line with predictions, differences between men and women disappeared after the mandate; but again, only for HOS compliance. Surprisingly, women had significantly more HOS violations in 2021 and 2022 than men—an outcome that may be tied to women truckers' personal safety issues. In summary, the results and additional robustness checks indicate that men committed more unsafe driving violations (e.g., speeding) than women across the entire study period, while the pattern of HOS violations varied based on external events. We conclude by highlighting possible pathways for reducing the number of collisions involving trucks and thus lowering the number of fatalities and extent of economic losses. [ABSTRACT FROM AUTHOR]

This study examined news images and captions published by The Associated Press (N = 7,455) between 2018 and 2022 to ascertain whether names were more frequently included for certain groups of people. The analysis found that people depicted in the Global North are named far more frequently than in the Global South, and that sports, entertainment, and political images include names more often than news and feature images. These pervasive patterns suggest naming has a discursive function that constructs an Other by excluding familial and cultural connotations inherent in names, forming a hierarchy through opposition, and extending social prominence for certain groups. [ABSTRACT FROM AUTHOR]

Give random capacities C to the edges of the complete n-vertex graph. Consider the maximum flow Φn that can be simultaneously routed between each source-destination pair. We prove that Φn → φ{symbol} in probability where the limit constant φ{symbol} depends on the distribution of C in a simple way, and that asymptotically one need use only 1- and 2-step routes. The proof uses a reduction to a random graph problem. © 2009 Elsevier B.V. All rights reserved.

Fix k > 0, and let G be a graph, with vertex set partitioned into k subsets ("blocks") of approximately equal size. An induced subgraph of G is "transversal" (with respect to this partition) if it has exactly one vertex in each block (and therefore it has exactly k vertices). A "pure pair" in G is a pair X,Y of disjoint subsets of V (G) such that either all edges between X,Y are present or none are; and in the present context we are interested in pure pairs (X,Y) where each of X,Y is a subset of one of the blocks, and not the same block. This paper collects several results and open questions concerning how large a pure pair must be present if various types of transversal subgraphs are excluded. [ABSTRACT FROM AUTHOR]

The logistics industry in the United States has faced significant labor shortages for the last couple of decades. Women are a source of labor that has been traditionally underrepresented in the major logistics sectors, transportation, and warehousing. We study the workforce composition and potential gender wage gap across these sectors. Using data from the U.S. Census Bureau from 2003 to 2020, we show that women comprise about 4% of the workforce for truck drivers and 21% for warehouse workers. As traditionally measured by economists, there is a 17% gender wage gap among truck drivers and an 11% wage gap among warehouse workers. A regression analysis suggests that the gap is smaller for warehouse workers, which is consistent with theory that an occupation's stability and predictability can reduce or eliminate wage gaps. Further analysis is carried out on specific occupations within the logistics industry and measures the variation across truck transportation and warehousing industries. There is evidence for a declining gender wage gap across both over time, although the gap remains sizable. This paper provides insight on the trends and status of gender differences in labor outcomes in the logistics industry. [ABSTRACT FROM AUTHOR]