Behavioral Communities and the Atomic Structure of Networks

We develop a theory of `behavioral communities' and the `atomic structure' of networks. We define atoms to be groups of agents whose behaviors always match each other in a set of coordination games played on the network. This provides a microfoundation for a method of detecting communities in social and economic networks. We provide theoretical results characterizing such behavior-based communities and atomic structures and discussing their properties in large random networks. We also provide an algorithm for identifying behavioral communities. We discuss applications including: a method of estimating underlying preferences by observing behavioral conventions in data, and optimally seeding diffusion processes when there are peer interactions and homophily. We illustrate the techniques with applications to high school friendship networks and rural village networks

Governing urban wetlands for green growth in the Western Region Megapolis of Sri Lanka

The Western Region Megapolis (WRM) of Sri Lanka, the conurbation associated with Greater Colombo and covering the entire Western Province, is the thriving economic center of the country. According to the State of Sri Lankan Cities 2018 report (GoSL 2018), the city accounts for 40% of Sri Lanka’s gross domestic product (GDP), 30% of its population and is the nation’s administrative center. The WRM is also endowed with wetlands of international importance. This includes the Bellanwila-Attidiya marshes: a 370-ha freshwater marsh in southern Colombo rich in biodiversity (Box 1); the Colombo Flood Detention Area: a 400-ha network of marshes and canals that traverse the DISCUSSION BRIEF An aerial view of the city of Colombo in Sri Lanka with its network of wetlands supporting urban dwellers - A hub for green growth. Photo: Martin Seemungal city; and the Muthurajawela marsh: a 2,500-ha saltwater marsh in northern Colombo, which is the largest saline peat bog in Sri Lanka (IUCN and CEA 2006). The aim of this brief is to support the efforts of the Government of Sri Lanka to leverage the WRM wetlands to foster green growth. Green growth promotes economic development alongside environmental sustainability, and is gaining traction as a model to achieve sustainable urban development globally (Hammer et al. 2011). According to OECD (2013: 9), governments promote green growth “to create jobs and attract firms and investment, while improving local environmental quality and addressing global environmental challenges, particularly climate change.

A People's History Of Recent Urban Transportation Innovation

Who are the people leading the charge in urban transportation? As our report explains, the short answer is that it takes leaders from three different sectors of urban society to make change happen quickly.First, there needs to be a robust civic vanguard, the more diverse their range of skills and participation, the better. Second, mayors, commissioners and other city leaders need to create the mandate and champion the change. The third sector is the agency staff. When these three sectors align, relatively quick transformation is possible. Several cities, including New York and Pittsburgh, recently experienced this alignment of a healthy civic community, a visionary and bold mayor and transportation head, and internal agency champions. Our report also highlighted the potential of other cities, such as Charlotte, where the civic sector continues to build on and widen their base

Child Exploitation and the FIFA World Cup: A review of risks and protective interventions

This review was commissioned by the Child Abuse Programme (CAP) of Oak Foundation, a large international philanthropic organisation. It forms part of CAP’s effort to win societal rejection of practices such as the sexual exploitation of children and adolescents around major sporting events (MSEs), and to embed prevention and protection from exploitation as a permanent concern for global sports-related bodies. This review is intended to inform action in countries that host MSEs and to provide some suggestions on how hosting countries can avoid past pitfalls and mistakes in relation to child exploitation, especially economic and sexual exploitation. Importantly, it also acts as a call to action by those responsible for commissioning and staging MSEs, such as FIFA and the IOC, to anticipate, prepare for and adopt risk mitigation strategies and interventions. Positive leadership from these culturally powerful bodies could prove decisive in shifting hearts, minds and actions in the direction of improved safety for children

A risk-security tradeoff in graphical coordination games

A system relying on the collective behavior of decision-makers can be vulnerable to a variety of adversarial attacks. How well can a system operator protect performance in the face of these risks? We frame this question in the context of graphical coordination games, where the agents in a network choose among two conventions and derive benefits from coordinating neighbors, and system performance is measured in terms of the agents' welfare. In this paper, we assess an operator's ability to mitigate two types of adversarial attacks - 1) broad attacks, where the adversary incentivizes all agents in the network and 2) focused attacks, where the adversary can force a selected subset of the agents to commit to a prescribed convention. As a mitigation strategy, the system operator can implement a class of distributed algorithms that govern the agents' decision-making process. Our main contribution characterizes the operator's fundamental trade-off between security against worst-case broad attacks and vulnerability from focused attacks. We show that this tradeoff significantly improves when the operator selects a decision-making process at random. Our work highlights the design challenges a system operator faces in maintaining resilience of networked distributed systems.Comment: 13 pages, double column, 4 figures. Submitted for journal publicatio

Chasing Efficiency Can operational changes fix European asylum systems? Bertelsmann Stiftung Migration Policy Institute Europe March 2020

The heightened arrivals of asylum seekers and migrants on European shores in 2015–16 sent policymakers across the continent scrambling for new strategies to manage migration. Proposals to reform the European Union’s legal framework for asylum were the first out of the starting blocks but, several years later, no such agreement has been reached. And with new EU leadership having taken office in late 2019, Brussels is hungry for fresh ideas that will either revive or reform the Common European Asylum System (CEAS). Crucial to this search will be a recognition that, while deficiencies still plague Europe’s asylum systems, these systems have changed significantly since the onset of the migration and refugee crisis—even in the absence of legal reforms