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Quantile models for the threshold range for k-connectivity

Henri Koskinen
2004 Proceedings of the 7th ACM international symposium on Modeling, analysis and simulation of wireless and mobile systems - MSWiM '04  
threshold range for k-connectivity when the nodes are uniformly distributed in a square region.  ...  This study addresses the problem of k-connectivity of a wireless multihop network consisting of randomly placed nodes with a common transmission range, by utilizing empirical regression models for the  ...  Bettstetter for allowing the use of his simulation results in this paper, and Jorma Virtamo and the anonymous reviewers for their helpful comments.  ... 
doi:10.1145/1023663.1023666 dblp:conf/mswim/Koskinen04 fatcat:a5hu3uk4n5ggdaqchkotrd6diu

Interspecific Sample Prioritization Can Improve QTL Detection With Tree-Based Predictive Models

Min-Gyoung Shin, Sergey V. Nuzhdin
2021 Frontiers in Genetics  
Due to increasing demand for new advanced crops, considerable efforts have been made to explore the improvement of stress and disease resistance cultivar traits through the study of wild crops.  ...  combining the two types of data.  ...  the corresponding marker rank range was from 3 to 3.4 for the 80% quantile and from 5 to 9.2 for the 90% quantile in other thresholds.  ... 
doi:10.3389/fgene.2021.684882 pmid:34552613 pmcid:PMC8450460 fatcat:ueordmvwlzf73klc5jos6cu244

Quantile hydrologic model selection and model structure deficiency assessment: 2. Applications

Saket Pande
2013 Water Resources Research  
The case study shows that an intuitive improvement in the model structure leads to reductions in asymmetric loss function values for all considered quantiles.  ...  It also shows that quantile model predictions are fairly robust. The second case study is of a parsimonious hydrological model for dry land areas in Western India.  ...  These ranges are similar to the ones reported by Schoups and Vrugt [2010] , except for K s , E , and Q pmax for the French Broad river basin.  ... 
doi:10.1002/wrcr.20422 fatcat:6xmrhagt65ggffnaxiaedci5hi

Wavelet and network analysis of magnetic field variation and geomagnetically induced currents during large storms

L. Orr, S. C. Chapman, C.D. Beggan
2021 Space Weather: The international journal of research and applications  
The complex interaction between the coupled magnetosphere-ionosphere and a highly perturbed solar wind produces large changes of the magnetic and  ...  The risk posed by space weather may last a significant period of time (i.e., hours to days), primarily from the advance and retreat of the auroral electrojet (Hapgood, 2019) .  ...  Almost all of the network nodes have a degree which is above the 90th quantile for the storm and there is a prevalence of long-range connections extending across the entire HV grid.  ... 
doi:10.1029/2021sw002772 fatcat:ka53jiwwtzbqrifmjq4fqtzu2q

Two new approaches for the visualisation of models for network meta-analysis

Martin Law, Navid Alam, Areti Angeliki Veroniki, Yi Yu, Dan Jackson
2019 BMC Medical Research Methodology  
Despite the variety of approaches available for presenting fitted models, ascertaining an intuitive understanding of these models is often difficult.  ...  Meta-analysis is a useful tool for combining evidence from multiple studies to estimate a pooled treatment effect.  ...  The funding body had no role in the writing of the manuscript.  ... 
doi:10.1186/s12874-019-0689-9 pmid:30885133 pmcid:PMC6423884 fatcat:ln6xmcnd4fgprfj33djcoehpqu

A generalized Spatio-Temporal Threshold Clustering method for identification of extreme event patterns

Vitaly Kholodovsky, Xin-Zhong Liang
2021 Advances in Statistical Climatology, Meteorology and Oceanography  
While various statistical and climate models have been developed for the purpose of simulating extremes, a consistent definition of extreme events is still lacking.  ...  The proposed method automates the threshold selection process through a clustering algorithm and can be directly applicable in conjunction with modeling and spatial forecast verification of extremes.  ...  The average silhouette coefficient Sil(K) can be used to evaluate the quality of segregation into K clusters, such as, for any finite K find max K Sil(K).  ... 
doi:10.5194/ascmo-7-35-2021 fatcat:n7pvadm3uje6lhdvt7m6pjrcou

Predictive Uncertainty Estimation of Hydrological Multi-Model Ensembles Using Pair-Copula Construction

Bastian Klein, Dennis Meissner, Hans-Ulrich Kobialka, Paolo Reggiani
2016 Water  
To estimate the PU of hydrological multi-model ensembles, we apply a method based on the use of copulas which enables modelling the dependency structures between variates independently of their marginal  ...  The proposed method is applied to a multi-model ensemble involving two hydrological and one statistical flow models at two gauge stations in the Moselle river basin.  ...  -U.K. implemented the ESN model for the two gauges in the Moselle river basin and provided useful suggestions to the manuscript.  ... 
doi:10.3390/w8040125 fatcat:cj35hdnt5fcmhguysgmtdratse

Estimating the upper tail of flood frequency distributions

James A. Smith
1987 Water Resources Research  
Quantile estimation procedures are developed for both annual peak and seasonal flood frequency distributions.  ...  The underlying model of flood peaks is a marked point process { rj. z}} where Tj represents time of occurrence of the j1h flood during year i and the mark z} represents magnitude of the flood peak.  ...  This research was carried out at the Centre for Mathematics and Computer Science in Amsterdam with the support of a Fullbright postdoctoral research grant.  ... 
doi:10.1029/wr023i008p01657 fatcat:da4pnku3angfhizkj75m3c2cle

Smooth Online Parameter Estimation for time varying VAR models with application to rat's LFP data [article]

Anass El Yaagoubi Bourakna, Marco Pinto, Norbert Fortin, Hernando Ombao
2022 arXiv   pre-print
Consequently, the models are fit in real-time even for high dimensional time series.  ...  As demonstrated in the video, the proposed SOPE method is able to capture the dynamics of the connectivity as the rat performs the sequence of non-spatial working memory tasks.  ...  Parameter estimates for a tv-VAR model with with model misspecification (lower K), P = 4, K = 4 and K = 2, pair of tetrodes (1, 3).  ... 
arXiv:2102.12290v3 fatcat:6aam5grsdbf2pjsrmbimjfshke

Advancing interpretation of stable isotope assignment maps: comparing and summarizing origins of known-provenance migratory bats

Caitlin J. Campbell, Matthew C. Fitzpatrick, Hannah B. Vander Zanden, David M. Nelson
2020 Animal Migration  
We then compared four approaches for inferring origins (cumulative-sum, odds-ratio, quantile-only, and quantile-simulation) across a range of thresholds and probable minimum distance traveled.  ...  The cumulative-sum and quantile-simulation approaches had generally higher precision at a given level of accuracy than the odds-ratio and quantile-only approaches, and many threshold values were associated  ...  Edward Gates, Paul Gugger, and Richard Raesly for providing feedback on early versions of this manuscript, as well as two anonymous reviewers for valuable input that improved the clarity of the text.  ... 
doi:10.1515/ami-2020-0004 fatcat:5dvtedgbs5cbfgzs77tu6w7yma

Non-Gaussian analysis methods for planing craft motion

Abhilash Somayajula, Jeffrey M. Falzarano
2014 Ocean Systems Engineering  
The peaks over threshold analysis and fitting of the Generalized Pareto Distribution are explored in this paper as an alternative to Weibull, Generalized Gamma and Rayleigh distributions in predicting  ...  Unlike the traditional displacement type vessels, the high speed planing crafts are supported by the lift forces which are highly non-linear.  ...  Robert Brizzolara for facilitating the funding for this work.  ... 
doi:10.12989/ose.2014.4.4.293 fatcat:id46b2fkxjhbzadk2psf6fnzca

Statistical Evaluation of Spectral Methods for Anomaly Detection in Networks [article]

Tomilayo Komolafe and A. Valeria Quevedo, Srijan Sengupta, William H. Woodall
2019 arXiv   pre-print
Monitoring of networks for anomaly detection has attracted a lot of attention in recent years especially with the rise of connected devices and social networks.  ...  However, application of these techniques to more complex network models is hindered by various challenges such as the size of the network being investigated, how much apriori information is needed, the  ...  For the Chung-Lu model, for each (n, p 0 ) combination, we generate a single network from the R-MAT model and use the observed degrees k = (k 1 , . . . , k n ) as model parameters for the Chung-Lu model  ... 
arXiv:1711.01378v4 fatcat:xe2iltibhjcsrljr3yooc2am3a

Bayesian versus frequentist upper limits [article]

Christian Röver, Chris Messenger, Reinhard Prix
2011 arXiv   pre-print
of the likelihood function over parameter space, while the other requires integration.  ...  Using a simple example (detection of a sinusoidal signal in white Gaussian noise), we investigate the differences in performance and interpretation, and the effect of the "trials factor", or "look-elsewhere  ...  j k ≤ N 2 − 1 defines the range of possible (Fourier) frequencies.  ... 
arXiv:1103.2987v3 fatcat:mmndkrpwgjhktdc6u6rvmb2t7m

Empirical Estimation of Return Period and Distribution of Duration of Wind Speed Exceedances

D. C. Kiplangat, K. Asokan, G. V. Drisya, K. Satheesh Kumar
2018 2018 IEEE Recent Advances in Intelligent Computational Systems (RAICS)  
Analysis of wind speed data from various locations reveals that the duration of both upper and lower exceedances can be modelled empirically by the exponential family of distributions very closely.  ...  We also demonstrate an extrapolation technique to accurately estimate the return period for time series of short duration.  ...  The probability plot is a comparison of empirical and model values of the distribution function for each exceedance, while the quantile plot compares the quantiles of the exceedances.  ... 
doi:10.1109/raics.2018.8634901 fatcat:vvq6omoyxvfunjlzpizccg7j7q

Groundwater decline and tree change in floodplain landscapes: Identifying non-linear threshold responses in canopy condition

J. Kath, K. Reardon-Smith, A.F. Le Brocque, F.J. Dyer, E. Dafny, L. Fritz, M. Batterham
2014 Global Ecology and Conservation  
Distinct non-linear responses were found, with groundwater depth thresholds identified in the range from 12.1 m to 22.6 m for E. camaldulensis and 12.6 m to 26.6 m for E. populnea beyond which canopy condition  ...  Boosted regression trees, quantile regression and Threshold Indicator Taxa Analysis were used to investigate the relationship between tree condition and groundwater depth.  ...  Acknowledgements This research was supported by the MDB Futures-Collaborative Research Network (CRN), the University of Southern Queensland's International Centre for Applied Climate Sciences and Digital  ... 
doi:10.1016/j.gecco.2014.09.002 fatcat:w5ivsoakg5e5zcytbr77qctrma
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