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Online social networks have become crucial to propagate information. Prominent use cases include marketing campaigns for products or political candidates in which maximizing the expected number of reached individuals is a common objective. The latter can be achieved by incentivizing an appropriately selected seed set of influencers that trigger an influence cascade with expected maximum impact. In real-world settings, competing influence spreads need to be considered frequently. These may, for instance, stem from marketing activities for a substitute product of a different company or bad actors that spread (mis-)information about a political candidate. This article focuses on competitive settings in which the seed individuals of one entity are already known. Another entity wants to choose its seed set of individuals that triggers an influence cascade of maximum impact. The propagation process is modeled by a variant of the probabilistic independent cascade model. An algorithmic framework based on a Benders decomposition is developed that also employs preprocessing and initial heuristics. This framework is used within a sample average approximation scheme that allows to approximate the exact objective function value. The algorithms are tested on real-world instances from the literature and newly-obtained ones from Twitter. A computational study reports on the algorithms' performance next to providing further insights. The latter are based on analyzing expected losses that are caused by competition, the gain from solving subproblems to optimality using the Benders decomposition based algorithm, and the influence of different seed set choices of the first entity.

ObjectiveThis article illustrates the commonality among the Oaxaca decomposition, mediation analysis, and path analysis used in various social science fields to decompose the effect of a predictor on the outcome into constituent components.MethodsA general approach is proposed that extends the Oaxaca decomposition to continuous predictors. It also removes one critical restriction on covariates in mediation analysis.ResultsAn empirical example shows that the effect of fathers' education on children's years of schooling primarily works through children's early skill development and educational aspirations.ConclusionThe proposed approach is easy to implement since it requires only two pieces of information: simple correlations and standardized regression coefficients.

The year 2005 in Lebanon was a year of great upheavals both as regards its relationship with neighboring Syria & its internal political equilibrium. Since the summer of 2004, Syrian influence has been in the West's sights, particularly those of France & the United States. Damascus has been enjoined to stop interfering in Lebanon & to help disarm the Hizbollah & Palestinian factions operating on Lebanese soil. The assassination of Prime Minister Rafik Hariri, after his resignation, hastened the evacuation of Syrian troops. The following months unleashed popular mobilization unprecedented in the country's history, but the hopes opened by this era of political emancipation were soon tarnished by the usual maneuvers of alliance-forging during the Spring elections of 2005. In the bellicose regional environment, the persistence of communitarian & political cleavages & vital questions such as the presidency of the Republic, continuing resistance & the future of Lebanese-Syrian relations perpetuate alarming scenarios for the future of Lebanon. Adapted from the source document.

"This manuscript is based on two years of ethnographic fieldwork in rural Missouri between 2005-2013. Pine spent time with meth cooks, recovery professionals, pastors, and narcotics agents. At the center of this story are the meth cooks themselves, and Pine's ethnography details their daily struggles. Beginning in the center of an exploded meth lab, Pine's performative, narrative-based work explores meth cooks as modern-day alchemists, combining and exploding again the everyday objects of late capitalism, walking the fine lines (and obviously crossing them) between illegal and legal amphetamines, pulling everyday objects like lighter fluids, frying pans, and kitchen matches into the realm of illegality"--