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Explained: Artificial Intelligence for Propensity Score Estimation in Multilevel Educational Settings
Although educational research and evaluation generally occur in multilevel settings, many analyses ignore cluster effects. Neglecting the nature of data from educational settings, especially in non-randomized experiments, can result in biased estimates with long-term consequences. Our manuscript improves the availability and understanding of artificial neural networks, an underutilized method trending in other disciplines. This method also shows promise for dealing with challenges faced by educational researchers, such as analyzing clustered data. Therefore, we simulated data to generalize the potential benefits of artificial neural networks to different data types. We also compared artificial neural networks to more familiar methods and investigated the time it demanded to perform each technique. Hence, readers can decide when it may be more appropriate to use one method instead of another
Risk Management Decision Making for Security and Trust in Hardware Supply Chains
Modern cyber-physical systems are enabled by electronic hardware and embedded systems. The security of these sub-components is a concern during the design and operational phases of cyber-physical system life cycles. Compromised electronics can result in mission-critical failures, unauthorized access, and other severe consequences. As systems become more complex and feature greater connectivity, system owners must make decisions regarding how to mitigate risks and ensure resilience and trust. This paper provides an overview of research efforts related to assessing and managing risks, resilience, and trust with an emphasis on electronic hardware and embedded systems. The research takes a decision-oriented perspective, drawing from the perspectives of scenario planning and portfolio analysis, and describes examples related to the risk-based prioritization of cyber assets in large-scale systems
Fundamental Concepts of Cyber Resilience: Introduction and Overview
Given the rapid evolution of threats to cyber systems, new management
approaches are needed that address risk across all interdependent domains
(i.e., physical, information, cognitive, and social) of cyber systems. Further,
the traditional approach of hardening of cyber systems against identified
threats has proven to be impossible. Therefore, in the same way that biological
systems develop immunity as a way to respond to infections and other attacks,
so too must cyber systems adapt to ever-changing threats that continue to
attack vital system functions, and to bounce back from the effects of the
attacks. Here, we explain the basic concepts of resilience in the context of
systems, discuss related properties, and make business case of cyber
resilience. We also offer a brief summary of ways to assess cyber resilience of
a system, and approaches to improving cyber resilience.Comment: This is a preprint version of a chapter that appears in the book
"Cyber Resilience of Systems and Networks," Springer 201
Dynamic edge effects in small mammal communities across a conservation-agricultural interface in Swaziland
Across the planet, high-intensity farming has transformed native vegetation into monocultures, decreasing biodiversity on a
landscape scale. Yet landscape-scale changes to biodiversity and community structure often emerge from processes
operating at local scales. One common process that can explain changes in biodiversity and community structure is the
creation of abrupt habitat edges, which, in turn, generate edge effects. Such effects, while incredibly common, can be highly
variable across space and time; however, we currently lack a general analytical framework that can adequately capture such
spatio-temporal variability. We extend previous approaches for estimating edge effects to a non-linear mixed modeling
framework that captures such spatio-temporal heterogeneity and apply it to understand how agricultural land-uses alter
wildlife communities. We trapped small mammals along a conservation-agriculture land-use interface extending 375 m into
sugarcane plantations and conservation land-uses at three sites during dry and wet seasons in Swaziland, Africa. Sugarcane
plantations had significant reductions in species richness and heterogeneity, and showed an increase in community
similarity, suggesting a more homogenized small mammal community. Furthermore, our modeling framework identified
strong variation in edge effects on communities across sites and seasons. Using small mammals as an indicator, intensive
agricultural practices appear to create high-density communities of generalist species while isolating interior species in less
than 225 m. These results illustrate how agricultural land-use can reduce diversity across the landscape and that effects can
be masked or magnified, depending on local conditions. Taken together, our results emphasize the need to create or retain
natural habitat features in agricultural mosaics.Texas A&M Agrilife Researchhttp://www.plosone.orgam2013Zoology and EntomologyMammal Research Institut
Plex: Towards Reliability using Pretrained Large Model Extensions
A recent trend in artificial intelligence is the use of pretrained models for
language and vision tasks, which have achieved extraordinary performance but
also puzzling failures. Probing these models' abilities in diverse ways is
therefore critical to the field. In this paper, we explore the reliability of
models, where we define a reliable model as one that not only achieves strong
predictive performance but also performs well consistently over many
decision-making tasks involving uncertainty (e.g., selective prediction, open
set recognition), robust generalization (e.g., accuracy and proper scoring
rules such as log-likelihood on in- and out-of-distribution datasets), and
adaptation (e.g., active learning, few-shot uncertainty). We devise 10 types of
tasks over 40 datasets in order to evaluate different aspects of reliability on
both vision and language domains. To improve reliability, we developed ViT-Plex
and T5-Plex, pretrained large model extensions for vision and language
modalities, respectively. Plex greatly improves the state-of-the-art across
reliability tasks, and simplifies the traditional protocol as it improves the
out-of-the-box performance and does not require designing scores or tuning the
model for each task. We demonstrate scaling effects over model sizes up to 1B
parameters and pretraining dataset sizes up to 4B examples. We also demonstrate
Plex's capabilities on challenging tasks including zero-shot open set
recognition, active learning, and uncertainty in conversational language
understanding.Comment: Code available at https://goo.gle/plex-cod
SoK: Contemporary Issues and Challenges to Enable Cyber Situational Awareness for Network Security
Cyber situational awareness is an essential part of cyber defense that allows the cybersecurity operators to cope with the complexity of today's networks and threat landscape. Perceiving and comprehending the situation allow the operator to project upcoming events and make strategic decisions. In this paper, we recapitulate the fundamentals of cyber situational awareness and highlight its unique characteristics in comparison to generic situational awareness known from other fields. Subsequently, we provide an overview of existing research and trends in publishing on the topic, introduce front research groups, and highlight the impact of cyber situational awareness research. Further, we propose an updated taxonomy and enumeration of the components used for achieving cyber situational awareness. The updated taxonomy conforms to the widely-accepted three-level definition of cyber situational awareness and newly includes the projection level. Finally, we identify and discuss contemporary research and operational challenges, such as the need to cope with rising volume, velocity, and variety of cybersecurity data and the need to provide cybersecurity operators with the right data at the right time and increase their value through visualization
Kepler-102: Masses and Compositions for a Super-Earth and Sub-Neptune Orbiting an Active Star
Kepler-102 : masses and compositions for a super-Earth and sub-Neptune orbiting an active star
Funding: This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under grant No. 1842402. C.L.B., L.W., and D.H. acknowledge support from National Aeronautics and Space Administration (grant No. 80NSSC19K0597) issued through the Astrophysics Data Analysis Program. D.H. also acknowledges support from the Alfred P. Sloan Foundation. K.R. acknowledges support from the UK STFC via grant No. ST/V000594/1. E.G. acknowledges support from NASA grant No. 80NSSC20K0957 (Exoplanets Research Program).Radial velocity (RV) measurements of transiting multiplanet systems allow us to understand the densities and compositions of planets unlike those in the solar system. Kepler-102, which consists of five tightly packed transiting planets, is a particularly interesting system since it includes a super-Earth (Kepler-102d) and a sub-Neptune-sized planet (Kepler-102e) for which masses can be measured using RVs. Previous work found a high density for Kepler-102d, suggesting a composition similar to that of Mercury, while Kepler-102e was found to have a density typical of sub-Neptune size planets; however, Kepler-102 is an active star, which can interfere with RV mass measurements. To better measure the mass of these two planets, we obtained 111 new RVs using Keck/HIRES and Telescopio Nazionale Galileo/HARPS-N and modeled Kepler-102's activity using quasiperiodic Gaussian process regression. For Kepler-102d, we report a mass upper limit Md < 5.3 M⊕ (95% confidence), a best-fit mass Md = 2.5 ± 1.4 M⊕, and a density ρd = 5.6 ± 3.2 g cm−3, which is consistent with a rocky composition similar in density to the Earth. For Kepler-102e we report a mass Me = 4.7 ± 1.7 M⊕ and a density ρe = 1.8 ± 0.7 g cm−3. These measurements suggest that Kepler-102e has a rocky core with a thick gaseous envelope comprising 2%–4% of the planet mass and 16%–50% of its radius. Our study is yet another demonstration that accounting for stellar activity in stars with clear rotation signals can yield more accurate planet masses, enabling a more realistic interpretation of planet interiors.Publisher PDFPeer reviewe
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