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  1. Abstract

    A stable-frequency transmitter with relative radial acceleration to a receiver will show a change in received frequency over time, known as a “drift rate.” For a transmission from an exoplanet, we must account for multiple components of drift rate: the exoplanet’s orbit and rotation, the Earth’s orbit and rotation, and other contributions. Understanding the drift rate distribution produced by exoplanets relative to Earth, can (a) help us constrain the range of drift rates to check in a Search for Extraterrestrial Intelligence project to detect radio technosignatures, and (b) help us decide validity of signals-of-interest, as we can compare drifting signals with expected drift rates from the target star. In this paper, we modeled the drift rate distribution for ∼5300 confirmed exoplanets, using parameters from the NASA Exoplanet Archive (NEA). We find that confirmed exoplanets have drift rates such that 99% of them fall within the ±53 nHz range. This implies a distribution-informed maximum drift rate ∼4 times lower than previous work. To mitigate the observational biases inherent in the NEA, we also simulated an exoplanet population built to reduce these biases. The results suggest that, for a Kepler-like target star without known exoplanets, ±0.44 nHz would be sufficient to account for 99% of signals. This reduction in recommended maximum drift rate is partially due to inclination effects and bias toward short orbital periods in the NEA. These narrowed drift rate maxima will increase the efficiency of searches and save significant computational effort in future radio technosignature searches.

     
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  2. This study examines the content and layout of the proposed broadband consumer disclosure labels mandated by the U.S. Federal Communications Commission (FCC). Our large-scale user study identifies key consumer preferences and comprehension factors through a two-phase survey of 2,500 broadband internet consumers. Findings reveal strong support for broadband labels, but dissatisfaction with the FCC's proposed labels from 2016. Participants generally struggled to use the label for cost computations and plan comparisons. Technical terms confused participants, but providing participants with brief education made the terms usable. Participants desired additional information, including reliability, speed measures for both periods when performance is “normal” and periods when performance is much worse than normal, quality-of-experience ratings, and detailed network management practices. This feedback informed our improved label designs that outperformed the 2016 labels in comprehension and preference. Overall, consumers valued clear pricing and performance details, comprehensive information, and an easy-to-understand format for plan comparison. Requiring broadband service providers to deposit machine-readable plan information in a publicly accessible database would enable third parties to further customize how information is presented to meet these consumer needs. Our work additionally highlights the need for user studies of labels to ensure they meet consumer demands. 
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  3. Many websites have added cookie consent interfaces to meet regulatory consent requirements. While prior work has demonstrated that they often use dark patterns — design techniques that lead users to less privacy-protective options — other usability aspects of these interfaces have been less explored. This study contributes a comprehensive, two-stage usability assessment of cookie consent interfaces. We first inspected 191 consent interfaces against five dark pattern heuristics and identified design choices that may impact usability. We then conducted a 1,109-participant online between-subjects experiment exploring the usability impact of seven design parameters. Participants were exposed to one of 12 consent interface variants during a shopping task on a prototype e-commerce website and answered a survey about their experience. Our findings suggest that a fully-blocking consent interface with in-line cookie options accompanied by a persistent button enabling users to later change their consent decision best meets several design objectives. 
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