Vasilis Verroios

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Given a set of records, an Entity Resolution (ER) algorithm finds records that refer to the same real-world entity. Humans can often determine if two records refer to the same entity, and hence we study the problem of selecting questions to ask error-prone humans. We give a Maximum Likelihood formulation for the problem of finding the “most(More)
A fundamental application in vehicular ad-hoc networks (VANETs) is the discovery of available parking spaces as vehicles navigate through urban road networks. Vehicles are now capable of finding such parking spots using their on-board sensing and computational infrastructure and then they can disseminate this information for use by other members of the(More)
We examine the problem of routing vehicles in a road network where traffic congestion affects the time required to traverse an edge. We propose a fully distributed approach that uses only the computational resources and communication capabilities of vehicles and requires no fixed infrastructure or centralized servers. Our approach bases its operation on(More)
Both economic reasons and interoperation requirements necessitate the deployment of IaaS-clouds based on a share-nothing architecture. Here, live VM migration becomes a major impediment to achieving cloud-wide load balancing via selective and timely VM-migrations. Our approach is based on copying virtual disk images and keeping them synchronized during the(More)
Crowdsourcing struggles when workers must see all of the pieces of input to make an accurate judgment. For example, to find the most important scenes in a novel or movie, each worker must spend hours consuming the entire plot to acquire a global understanding and then apply that understanding to each local scene. To enable the crowdsourcing of large-scale(More)
Cooperative Collision Warning Systems (CCWSs) have become a major vehicle safety application in intelligent transportation systems. Vehicles organized in a vehicular ad-hoc network use a CCWS communication protocol to propagate emergency messages about hazardous events. Police cars, ambulances responding to incidents and speeding cars or motorcycles that(More)
Crowdsourcing refers to solving large problems by involving human workers that solve component sub-problems or tasks. In data crowdsourcing, the problem involves data acquisition, management, and analysis. In this paper, we provide an overview of data crowdsourcing, giving examples of problems that the authors have tackled, and presenting the key design(More)
Latency is a critical factor when using a crowdsourcing platform to solve a problem like entity resolution or sorting. In practice, most frameworks attempt to reduce latency by heuristically splitting a budget of questions into rounds, so that after each round the answers are analyzed and new questions are selected. We focus on one of the most extensively(More)
In Entity Resolution, the objective is to find which records of a dataset refer to the same real-world entity. Crowd Entity Resolution uses humans, in addition to machine algorithms, to improve the quality of the outcome. We study a hybrid approach that combines two common interfaces for human tasks in Crowd Entity Resolution, taking into account key(More)
An important problem that online work marketplaces face is grouping clients into clusters, so that in each cluster clients are similar with respect to their hiring criteria. Such a separation allows the marketplace to "learn" more accurately the hiring criteria in each cluster and recommend the right contractor to each client, for a successful(More)