Tracking the Actions and Possessions of Agents

We propose that there is a powerful human disposition to track the actions and possessions of agents. In two experiments, 3‐year‐olds and adults viewed sets of objects, learned a new fact about one of the objects in each set (either that it belonged to the participant, or that it possessed a particular label), and were queried about either the taught fact or an unrelated dimension (preference) immediately after a spatiotemporal transformation, and after a delay. Adults uniformly tracked object identity under all conditions, whereas children tracked identity more when taught ownership versus labeling information, and only regarding the taught fact (not the unrelated dimension). These findings suggest that the special attention that children and adults pay to agents readily extends to include inanimate objects. That young children track an object's history, despite their reliance on surface features on many cognitive tasks, suggests that unobservable historical features are foundational in human cognition.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109337/1/tops12106.pd

Generating Long-term Trajectories Using Deep Hierarchical Networks

We study the problem of modeling spatiotemporal trajectories over long time horizons using expert demonstrations. For instance, in sports, agents often choose action sequences with long-term goals in mind, such as achieving a certain strategic position. Conventional policy learning approaches, such as those based on Markov decision processes, generally fail at learning cohesive long-term behavior in such high-dimensional state spaces, and are only effective when myopic modeling lead to the desired behavior. The key difficulty is that conventional approaches are "shallow" models that only learn a single state-action policy. We instead propose a hierarchical policy class that automatically reasons about both long-term and short-term goals, which we instantiate as a hierarchical neural network. We showcase our approach in a case study on learning to imitate demonstrated basketball trajectories, and show that it generates significantly more realistic trajectories compared to non-hierarchical baselines as judged by professional sports analysts.Comment: Published in NIPS 201

Verifying Security Properties in Unbounded Multiagent Systems

We study the problem of analysing the security for an unbounded number of concurrent sessions of a cryptographic protocol. Our formal model accounts for an arbitrary number of agents involved in a protocol-exchange which is subverted by a Dolev-Yao attacker. We define the parameterised model checking problem with respect to security requirements expressed in temporal-epistemic logics. We formulate sufficient conditions for solving this problem, by analysing several finite models of the system. We primarily explore authentication and key-establishment as part of a larger class of protocols and security requirements amenable to our methodology. We introduce a tool implementing the technique, and we validate it by verifying the NSPK and ASRPC protocols

Use of Machine Learning to Automate the Identification of Basketball Strategies Using Whole Team Player Tracking Data

The use of machine learning to identify and classify offensive and defensive strategies in team sports through spatio-temporal tracking data has received significant interest recently in the literature and the global sport industry. This paper focuses on data-driven defensive strategy learning in basketball. Most research to date on basketball strategy learning has focused on offensive effectiveness and is based on the interaction between the on-ball player and principle on-ball defender, thereby ignoring the contribution of the remaining players. Furthermore, most sports analytical systems that provide play-by-play data is heavily biased towards offensive metrics such as passes, dribbles, and shots. The aim of the current study was to use machine learning to classify the different defensive strategies basketball players adopt when deviating from their initial defensive action. An analytical model was developed to recognise the one-on-one (matched) relationships of the players, which is utilised to automatically identify any change of defensive strategy. A classification model is developed based on a player and ball tracking dataset from National Basketball Association (NBA) game play to classify the adopted defensive strategy against pick-and-roll play. The methodology described is the first to analyse the defensive strategy of all in-game players (both on-ball players and off-ball players). The cross-validation results indicate that the proposed technique for automatic defensive strategy identification can achieve up to 69% accuracy of classification. Machine learning techniques, such as the one adopted here, have the potential to enable a deeper understanding of player decision making and defensive game strategies in basketball and other sports, by leveraging the player and ball tracking data

The Forgotten Right "to Be Secure"

Surveillance methods in the United States operate under the general principle that “use precedes regulation.” While the general principle of “use precedes regulation” is widely understood, its societal costs have yet to be fully realized. In the period between “initial use” and “regulation,” government actors can utilize harmful investigative techniques with relative impunity. Assuming a given technique is ultimately subjected to regulation, its preregulation uses are practically exempted from any such regulation due to qualified immunity (for the actor and municipality) and the exclusionary rule’s good faith exception (for any resulting evidence). This expectation of impunity invites strategic government actors to make frequent and arbitrary uses of harmful investigative techniques during preregulation periods. Regulatory delays tend to run long (often a decade or more) and are attributable in no small part to the stalling methods of law enforcement (through assertions of privilege, deceptive funding requests, and strategic sequencing of criminal investigations). While the societal costs of regulatory delay are high, rising, and difficult to control, the conventional efforts to shorten regulatory delays (through expedited legislation and broader rules of Article III standing) have proved ineffective. This Article introduces an alternative method to control the costs of regulatory delay: locating rights to be “protected” and “free from fear” in the “to be secure” text of the Fourth Amendment. Courts and most commentators interpret the Fourth Amendment to safeguard a mere right to be “spared” unreasonable searches and seizures. A study of the “to be secure” text, however, suggests that the Amendment can be read more broadly: to guarantee a right to be “protected” against unreasonable searches and seizures, and possibly a right to be “free from fear” against such government action. Support for these broad readings of “to be secure” is found in the original meaning of “secure,” the Amendment’s structure, and founding-era discourse regarding searches and seizures. The rights to be “protected” and “free from fear” can be adequately safeguarded by a judicially-created rule against government “adoption” of an investigative method that constitutes an unregulated and unreasonable search or seizure. The upshot of this Fourth Amendment rule against “adoption” is earlier standing to challenge the constitutionality of concealed investigative techniques. Earlier access to courts invites earlier j

Find it: an assistant home agent

Cognitive impaired population face with innumerable problems in their daily life. Surprisingly, they are not provided with any help to perform those tasks for which they have difficulties. As a consequence, it is necessary to develop systems that allow those people to live independently and autonomously. Living in a technological era, people could take advantage of the available technology, being provided with some solutions to their needs. This paper presents a platform that assists users with remembering where their possessions are. Mainly, an object recognition process together with an intelligent scheduling applications are integrated in an Ambient Assisted Living (AAL) environment.(undefined

Caution! Government Intrusion May Be Closer Than It Appears: The Seventh Circuit Considers GPS Devices Under the Fourth Amendment

The Fourth Amendment provides protection for individuals from unreasonable searches and seizures of their persons, property, and effects. However, as technology advances and the need for security in this country increases, individuals’ Fourth Amendment rights are in danger. Global Positioning System (“GPS”) tracking devices can now be easily installed on anyone’s car. The GPS device can then track that person’s movement for an extended period of time through the use of sophisticated computer and satellite technology. Under the current state of the law, the police are able to place these GPS devices on cars or possessions without reasonable suspicion, probable cause, or a warrant. This convergence of rapidly improving technology and Fourth Amendment rights has created a novel legal issue: If the police install a GPS device without first proving reasonable suspicion or probable cause, or without first obtaining a warrant, have they violated the Fourth Amendment? The Seventh Circuit recently addressed this issue in United States v. Garcia. In Garcia, the Seventh Circuit found that the installation of a GPS device did not constitute a search. Therefore, there was no Fourth Amendment violation. However, in deciding Garcia, the Seventh Circuit made errors in its reasoning. The court should have found that installing a GPS device constitutes a search; therefore, a warrant should be required prior to installation. Such a holding would allow police to use GPS devices without violating the Fourth Amendment. The focus of this Comment is not to question whether police should use GPS technology, but rather to argue that police should be required, before using GPS technology, to successfully pass through the gatekeeping functions set out to protect individuals’ Fourth Amendment rights