Schools in the US are installing vape-detection tech in bathrooms to thwart student nicotine and cannabis use. A new investigation reveals the impact of using spying to solve a problem. It was in physical education class when Laila Gutierrez swapped out self-harm for a new vice. The freshman from Phoenix had long struggled with depression and would cut her arms to feel something. The first drag from a friend's vape several years ago offered the shy teenager a new way to escape. She quit cutting but got hooked on nicotine. Her sadness got harder to carry after her uncle died, and she felt she couldn't turn to her grieving parents for comfort. Bumming fruity vapes at school became part of her routine. "I would ask my friends who had them, 'I'm going through a lot, can I use it?'" Gutierrez, now 18, told The 74. "Or'I failed my test and I feel like smoking would be better than cutting my wrists.'"

Things to Do in L.A. Tap to enable a layout that focuses on the article. A killer targeted men using Grindr, police say. The Grindr logo is seen among other dating apps on a mobile phone screen. This is read by an automated voice. Please report any issues or inconsistencies here .

Things to Do in L.A. Tap to enable a layout that focuses on the article. Online dating murder suspect lured men into brutal robberies, L.A. County prosecutors allege Rockim Prowell allegedly met his victims online. Above, a person uses a cellphone. Rockim Prowell, 44, fis accused of murder, attempted murder, carjacking and burglary. Prosecutors allege Prowell lured robbery victims using a dating site.

Concurrent multi-player mean-payoff games are important models for systems of agents with individual, non-dichotomous preferences. Whilst these games have been extensively studied in terms of their equilibria in non-cooperative settings, this paper explores an alternative solution concept: the core from cooperative game theory. This concept is particularly relevant for cooperative AI systems, as it enables the modelling of cooperation among agents, even when their goals are not fully aligned. Our contribution is twofold. First, we provide a characterisation of the core using discrete geometry techniques and establish a necessary and sufficient condition for its non-emptiness. We then use the characterisation to prove the existence of polynomial witnesses in the core. Second, we use the existence of such witnesses to solve key decision problems in rational verification and provide tight complexity bounds for the problem of checking whether some/every equilibrium in a game satisfies a given LTL or GR(1) specification. Our approach is general and can be adapted to handle other specifications expressed in various fragments of LTL without incurring additional computational costs.

We consider the problem of incentivising desirable behaviours in multi-agent systems by way of taxation schemes. Our study employs the concurrent games model: in this model, each agent is primarily motivated to seek the satisfaction of a goal, expressed as a Linear Temporal Logic (LTL) formula; secondarily, agents seek to minimise costs, where costs are imposed based on the actions taken by agents in different states of the game. In this setting, we consider an external principal who can influence agents' preferences by imposing taxes (additional costs) on the actions chosen by agents in different states. The principal imposes taxation schemes to motivate agents to choose a course of action that will lead to the satisfaction of their goal, also expressed as an LTL formula. However, taxation schemes are limited in their ability to influence agents' preferences: an agent will always prefer to satisfy its goal rather than otherwise, no matter what the costs. The fundamental question that we study is whether the principal can impose a taxation scheme such that, in the resulting game, the principal's goal is satisfied in at least one or all runs of the game that could arise by agents choosing to follow game-theoretic equilibrium strategies. We consider two different types of taxation schemes: in a static scheme, the same tax is imposed on a state-action profile pair in all circumstances, while in a dynamic scheme, the principal can choose to vary taxes depending on the circumstances. We investigate the main game-theoretic properties of this model as well as the computational complexity of the relevant decision problems.

US AI guidelines are everything the EU's AI Act is not: voluntary, non-prescriptive and focused on changing the culture of tech companies. As the EU's Artificial Intelligence (AI) Act fights its way through multiple rounds of revisions at the hands of MEPs, in the US a little-known organisation is quietly working up its own guidelines to help channel the development of such a promising and yet perilous technology. In March, the Maryland-based National Institute of Standards and Technology (NIST) released a first draft of its AI Risk Management Framework, which sets out a very different vision from the EU. The work is being led by Elham Tabassi, a computer vision researcher who joined the organisation just over 20 years ago. Then, "We built [AI] systems just because we could," she said.

Reactive Modules is a high-level modelling language for concurrent, distributed, and multi-agent systems, which is used in a number of practical model checking tools. Reactive Modules Games are a game-theoretic extension of Reactive Modules, in which agents in a system are assumed to act strategically in an attempt to satisfy a temporal logic formula representing their individual goal. Reactive Modules Games with perfect information have been closely studied, and the complexity of game theoretic decision problems relating to such games have been comprehensively classified. However, to date, no work has considered the imperfect information case. In this paper we address this gap, investigating Reactive Modules Games in which agents have only partial visibility of their environment.

In 2014, music fans and critics began paying close attention to a mysterious group of artists who'd started releasing tracks online. They were part of PC Music, a loose electronic-music collective that functioned more like a conceptual-art project. Led by a young, inventive producer from London named A. G. Cook, PC Music, and its affiliates, rejected a dark, murky strain of underground electronic music that was beloved at the time. Instead, they latched onto the most exuberant and absurd elements of pop, making cutesy, theatrical songs that sounded a bit like children's music, but with an unsettling aftertaste. If mainstream pop is designed to make people feel as if they're on common ground with all of humanity, this music made listeners feel like they were in on a very specific joke.

Rational verification is the problem of determining which temporal logic properties will hold in a multi-agent system, under the assumption that agents in the system act rationally, by choosing strategies that collectively form a game-theoretic equilibrium. Previous work in this area has largely focussed on deterministic systems. In this paper, we develop the theory and algorithms for rational verification in probabilistic systems. We focus on concurrent stochastic games (CSGs), which can be used to model uncertainty and randomness in complex multi-agent environments. We study the rational verification problem for both non-cooperative games and cooperative games in the qualitative probabilistic setting. In the former case, we consider LTL properties satisfied by the Nash equilibria of the game and in the latter case LTL properties satisfied by the core. In both cases, we show that the problem is 2EXPTIME-complete, thus not harder than the much simpler verification problem of model checking LTL properties of systems modelled as Markov decision processes (MDPs).

In the Marvel Cinematic Universe, the so-called normal people are often nonessential. We get in the way, we muck things up, we need help, we get turned to dust and in the case of last year's "WandaVision," we mortals exist mostly to be playthings for those with powers. Disney California Adventure's Avengers Campus aims to flip the script. Superheroes, they're just like us, the land argues. They get captured, they need our help, they make mistakes and sometimes they just have to do dreary, daily work.