- Soil Geostatistics and Mapping
- Climate variability and models
- Atmospheric and Environmental Gas Dynamics
- Meteorological Phenomena and Simulations
- Hydrology and Drought Analysis
- Spatial and Panel Data Analysis
- Gaussian Processes and Bayesian Inference
- Statistical Methods and Inference
- Scientific Research and Discoveries
- Financial Risk and Volatility Modeling
- Plant Water Relations and Carbon Dynamics
- Point processes and geometric inequalities
- Advanced Statistical Methods and Models
- Geochemistry and Geologic Mapping
- Advanced Multi-Objective Optimization Algorithms
- Statistical and numerical algorithms
- Probabilistic and Robust Engineering Design
- Atmospheric Ozone and Climate
- Tree-ring climate responses
- Remote Sensing in Agriculture
- demographic modeling and climate adaptation
- Air Quality and Health Impacts
- Bayesian Methods and Mixture Models
- Control Systems and Identification
- Marine and coastal ecosystems
Rutgers, The State University of New Jersey
2020-2024
University of Chicago
2013-2023
Rutgers Sexual and Reproductive Health and Rights
2019
The University of Adelaide
2016
King Abdullah University of Science and Technology
2015
University of Science and Technology
2015
North Carolina State University
2008-2013
Argonne National Laboratory
2013
Universidade Federal de Pelotas
2012
George Washington University
2010
Preliminaries. Structural Analysis. Kriging. Intrinsic Model of Order k. Multivariate Methods. Nonlinear Conditional Simulations. Scale Effects and Inverse Problems. Appendix. References. Index.
1 Linear Prediction.- 1.1 Introduction.- 1.2 Best linear prediction.- Exercises.- 1.3 Hilbert spaces and 1.4 An example of a poor BLP.- 1.5 unbiased 1.6 Some recurring themes.- The Matern model.- BLPs BLUPs.- Inference for differentiable random fields.- Nested models are not tenable.- 1.7 Summary practical suggestions.- 2 Properties Random Fields.- 2.1 Preliminaries.- Stationarity.- Isotropy.- Exercise.- 2.2 turning bands method.- 2.3 Elementary properties autocovariance functions.- 2.4 Mean...
Latin hypercube sampling (McKay, Conover, and Beckman 1979) is a method of that can be used to produce input values for estimation expectations functions output variables. The asymptotic variance such an estimate obtained. also shown asymptotically normal. Asymptotically, the less than obtained using simple random sampling, with degree reduction depending on additivity in function being integrated. A producing samples when components variables are statistically dependent described. These...
Latin hypercube sampling (McKay, Conover, and Beckman 1979) is a method of that can be used to produce input values for estimation expectations functions output variables. The asymptotic variance such an estimate obtained. also shown asymptotically normal. Asymptotically, the less than obtained using simple random sampling, with degree reduction depending on additivity in function being integrated. A producing samples when components variables are statistically dependent described. These...
This article is concerned with predicting for Gaussian random fields in a way that appropriately deals uncertainty the covariance function. To this end, we analyze best linear unbiased prediction procedure within Bayesian framework. Particular attention paid to treatment of parameters structure and their effect on quality, both real perceived, prediction. These ideas are implemented using topographical data from Davis.
Summary Likelihood methods are often difficult to use with large, irregularly sited spatial data sets, owing the computational burden. Even for Gaussian models, exact calculations of likelihood n observations require O(n3) operations. Since any joint density can be written as a product conditional densities based on some ordering observations, one way lessen computations is condition only ‘past’ when computing densities. We show how this approach adapted approximate restricted and we...
This work considers a number of properties space–time covariance functions and how these relate to the spatial-temporal interactions process. First, it examines smoothness away from origin function affects, for example, temporal correlations spatial differences. Models that are not smoother than they at origin, such as separable models, have kind discontinuity certain one might wish avoid in some circumstances. Smoothness is shown follow corresponding spectral density having derivatives with...
Objectives To compare injury patterns resulting from explosions in the open air versus within confined spaces. Methods Medical charts of 297 victims four bombing events were analyzed. Two occurred and two inside buses. Similar explosive devices applied all incidents. The incidence primary blast injuries, significant penetrating trauma (Abbreviated Injury Scale Score, > or = 2), burns, Severity Revised Trauma mortality compared between populations. Results A total 204 casualties involved...
I: Wind Data Analysis.- 1. Introduction.- 1.1. Surface Observation.- 1.2. General Weather Pattern.- 1.3. Outline of this Monograph.- 2. The Initial Decomposition.- 2.1. Background.- 2.2. Robust Filtering.- 2.3. Univariate Filter Study.- 2.4. Multivariate 2.5. Application to Series.- 2.6. Appendix: Mathematical Details.- 3. Geostrophic Component.- 3.1. Wind.- 3.2. Estimation the 3.3. Comparison with 3.4. Synoptic States.- 3.5. Derivation Equation.- 4. Land and Sea Breeze Cycle.- 4.1. Nature...
With the widespread availability of satellite-based instruments, many geophysical processes are measured on a global scale and they often show strong nonstationarity in covariance structure. In this paper we present flexible class parametric models that can capture data, especially dependency structure latitudes. We apply Discrete Fourier Transform to data regular grids, which enables us calculate exact likelihood for large sets. Our model is applied total column ozone level given day....
Statistical downscaling methods (SDMs) are often used to increase the resolution of future climate projections from coupled atmosphere‐ocean general circulation models (GCMs). However, SDMs not able capture small‐scale dynamical changes unresolved by GCMs. For this reason, we propose a two‐step generalized validation process evaluate performance any statistical method relative regional model (RCM) simulations driven same GCM fields. First, compare historical station‐based observations with...
Abstract The authors describe a new approach for emulating the output of fully coupled climate model under arbitrary forcing scenarios that is based on small set precomputed runs from model. Temperature and precipitation are expressed as simple functions past trajectory atmospheric CO2 concentrations, statistical fit using limited training runs. demonstrated to be useful computationally efficient alternative pattern scaling captures nonlinear evolution spatial patterns anomalies inherent in...
Climate models robustly imply that some significant change in precipitation patterns will occur. Models consistently project the intensity of individual events increases by approximately 6-7%/K, following increase atmospheric water content, but total a lesser amount (1-2 %/K global average transient runs). Some other aspect must then to compensate for this difference. We develop here new methodology identifying rainstorms and studying their physical characteristics - including starting...
CR Climate Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsSpecials 34:169-184 (2007) - DOI: https://doi.org/10.3354/cr00696 Statistical downscaling of precipitation through nonhomogeneous stochastic weather typing M. Vrac1,5,*, Stein2, K. Hayhoe3,4 1Center for Integrating and Environmental Science, The University Chicago, 5734 S. Ellis Avenue, Illinois 60637, USA 2Department Statistics,...
Best linear unbiased predictors of a random field can be obtained if the covariance function is specified correctly. Consider defined on bounded region $R$. We wish to predict $z(\cdot)$ at point $x$ in $R$ based observations $z(x_1), z(x_2), \ldots, z(x_N)$ $R$, where $\{x_i\}^\infty_{i = 1}$ has as limit but does not contain $x$. Suppose misspecified, an equivalent (mutually absolutely continuous) corresponding Gaussian measure true function. Then predictor $z(x)$ will asymptotically...
AbstractFor space–time processes on global or large scales, it is critical to use models that respect the Earth's spherical shape. The covariance functions of such should be not only positive definite sphere × time, but also capable capturing dynamics well. We develop time are flexible in producing interactions, especially asymmetries. Our idea consider a sum independent which each process obtained by applying first-order differential operator fully symmetric time. resulting can produce...
Global climate models aim to reproduce physical processes on a global scale and predict quantities such as temperature given some forcing inputs. We consider ensembles made of collections runs with different initial conditions scenarios. The purpose this work is show how the simulated temperatures in ensemble can be reproduced (emulated) space/time statistical model that addresses issue capturing nonstationarities latitude more effectively than current alternatives literature. we propose...
Abstract. Changes in extreme weather may produce some of the largest societal impacts anthropogenic climate change. However, it is intrinsically difficult to estimate changes events from short observational record. In this work we use millennial runs Community Climate System Model version 3 (CCSM3) equilibrated pre-industrial and possible future (700 1400 ppm CO2) conditions examine both how extremes change model well these can be estimated as a function run length. We distributions...