A defensive k-alliance in a graph is a set S of vertices with the property that every vertex in S has at least k more neighbors in S than it has outside of S. A defensive k-alliance S is called global if it forms a dominating set. In this paper we study the problem of partitioning the vertex set of a graph into (global) defensive k-alliances. The (global) defensive k-alliance partition number o...

The amount of raw information available for basketball analytics has been given a great boost with the availability of player tracking data. This facilitates detailed analyses of player movement patterns. In this paper, we focus on the difficult problem of offensive playcall classification. While outstanding individual players are crucial for the success of a team, the strategies that a team ca...

This paper studies a baseball statistic that plays the role of an offensive earned-run average (OERA). The OERA of an individual i s simply the number of earned runs per game that he would score if he batted in all nine positions in the line-up. Evaluation can be performed by hand b y scoring the sequence of times at bat of a given batter. This statistic has the obvious natural interpretation a...

Automated filters are commonly used in on line chat to stop users from sending malicious messages such as age-inappropriate language, bullying, and asking users to expose personal information. Rule based filtering systems are the most common way to deal with this problem but people invent increasingly subtle ways to disguise their malicious messages to bypass such filtering systems. Machine lea...

Botnets, consisting of thousands of interconnected remote-controlled computers, pose a big threat against the Internet. We have witnessed the involvement of such malicious infrastructures in politically motivated attacks in more than once recent years. Classical countermeasures are mostly reactive and conducted as part of incident response actions. This is often not sufficient. We argue that pr...

Over the years since their meager beginnings, agribusiness cooperatives in the U.S. have compiled a checkered history of both praise and condemnation. Some observers have argued that cooperatives no longer communicate with, nor represent the best interests of their farmer members. Some critics suggest that cooperatives have stymied, or at least diffused, free market transactions in the agricult...

Botnets, consisting of thousands of interconnected, remote-controlled computers, pose a big threat against the Internet. We have witnessed the involvement of such malicious infrastructures in politically motivated attacks more than once in recent years. Classical countermeasures are mostly reactive and conducted as part of incident response actions. This is often not sufficient. We argue that p...

Although in theory opponent modeling can be useful in any adversarial domain, in practice it is both difficult to do accurately and to use effectively to improve game play. In this paper, we present an approach for online opponent modeling and illustrate how it can be used to improve offensive performance in the Rush 2008 football game. In football, team behaviors have an observable spatio-temp...

The NFL and NCAA Football are multi-billion dollar industry. Despite this, the process of preparing to face an opponent is a relative anachronism. Coaches watch and take notes of their opponents' game footage the week before game day. When it comes time to call plays, they rely on their memory and instincts in order to call the proper play. A defense would be at a distinct advantage if their co...