448,852 research outputs found
Shake well before use: Authentication based on Accelerometer Data
Small, mobile devices without user interfaces, such as Bluetooth headsets, often need to communicate securely over wireless networks. Active attacks can only be prevented by authenticating wireless communication, which is problematic when devices do not have any a priori information about each other. We introduce a new method for device-to-device authentication by shaking devices together. This paper describes two protocols for combining cryptographic authentication techniques with known methods of accelerometer data analysis to the effect of generating authenticated, secret keys. The protocols differ in their design, one being more conservative from a security point of view, while the other allows more dynamic interactions. Three experiments are used to optimize and validate our proposed authentication method
The Information Complexity of Learning Tasks, their Structure and their Distance
We introduce an asymmetric distance in the space of learning tasks, and a
framework to compute their complexity. These concepts are foundational for the
practice of transfer learning, whereby a parametric model is pre-trained for a
task, and then fine-tuned for another. The framework we develop is
non-asymptotic, captures the finite nature of the training dataset, and allows
distinguishing learning from memorization. It encompasses, as special cases,
classical notions from Kolmogorov complexity, Shannon, and Fisher Information.
However, unlike some of those frameworks, it can be applied to large-scale
models and real-world datasets. Our framework is the first to measure
complexity in a way that accounts for the effect of the optimization scheme,
which is critical in Deep Learning
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Does the value of quality of life depend on duration?
The aims of this study are to investigate the feasibility of eliciting Time Trade Off (TTO) valuations using short durations; to determine the effect of contrasting durations on individualsā responses to the TTO; to examine variations within and between respondentsā values with respect to duration; and to consider the insights provided by participantsā comments and explanations regarding their reaction to duration in the valuation task. 27 participants provided TTO values using short and long durations for three EQ-5D states. Feedback was sought using a series of open ended questions. Of the 81 opportunities to observe it, strict constant proportionality was satisfied twice. 11 participants had no systematic relationship between duration and value; 11 provided consistently lower valuations in long durations, while 5 had higher valuations in long durations. Comments provided by participants were consistent with the values they provided. Mean TTO values did not differ markedly between alternative durations. We conclude that it is feasible to elicit TTO values for short durations. There is considerable heterogeneity in individualsā responses to the time frames used to elicit values. Further research is required to ensure that the values used in cost effectiveness analysis adequately represent preferences about quality and length of life
The theory of incentives applied to the transport sector
Building upon Iossa and Martimort (2008), we study the main incentive issues and the form of optimal contracts for Public Private Partnerships (PPPs) in transports. We present a basic model of procurement in a multitask environment in which a risk-averse firm chooses unobservable efforts in infrastructure and service quality. We begin by analyzing the effect on incentives and risk transfer of bundling building and operation into a single contract. We consider the factors that affect the optimal allocation of demand risk and their implications for the choice of contract length. We discuss the dynamics of PPP contracts and how the risk of regulatory opportunism affects contract design and incentives
Can I Have Your Attention? Implications of the Research on Distractions and Multitasking for Reference Librarians
The media have identified the last decade as āthe age of distraction.ā People today find it harder to work on long, sustained tasks because distractions are eroding their attention span, fostering a culture of discontinuity. Fields as diverse as psychology, business, education, human-computer interaction, and communication studies have produced a wealth of studies on interruptions, distractions, and multitaskingāresearch that has important implications for reference librarians. The nature of our jobs invites interruptions by the public, requires familiarity with the latest technology, stimulates curiosity about a broad range of subjects, and demands adeptness at multitaskingāall factors which can atomize attention
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