Data Driven Computing by the Morphing Fast Fourier Transform Ensemble Kalman Filter in Epidemic Spread Simulations

The FFT EnKF data assimilation method is proposed and applied to a stochastic cell simulation of an epidemic, based on the S-I-R spread model. The FFT EnKF combines spatial statistics and ensemble filtering methodologies into a localized and computationally inexpensive version of EnKF with a very small ensemble, and it is further combined with the morphing EnKF to assimilate changes in the position of the epidemic.Comment: 11 pages, 3 figures. Submitted to ICCS 201

Statistical catastrophe theory: An overview

AbstractThis paper is a summary of an address given to the Conference on Frontiers of Applied Geometry. A stochastic version of catastrophe theory is presented, using stochastic differential equations. We show that there is a nontrivial relationship between the potential functions of the deterministic models and the stationary probability density functions of the stochastic models. In the second part of the paper, we use maximum likelihood theory to derive estimators for the stationary densities, and we demonstrate how to test statistical hypotheses for these models

Estimation Theory for the Cusp Catastrophe Model

The cusp model of catastrophe theory is very closely related to certain multiparameter exponential families of probability density functions. This relationship is exploited to create an estimation theory for the cusp model. An example is presented in which an independent variable has a bifurcation effect on the dependent variable

Estimation Theory for the Cusp Catastrophe Model

The cusp model of catastrophe theory is very closely related to certain multiparameter exponential families of probability density functions. This relationship is exploited to create an estimation theory for the cusp model. An example is presented in which an independent variable has a bifurcation effect on the dependent variable

On the Convergence of the Ensemble Kalman Filter

Convergence of the ensemble Kalman filter in the limit for large ensembles to the Kalman filter is proved. In each step of the filter, convergence of the ensemble sample covariance follows from a weak law of large numbers for exchangeable random variables, Slutsky’s theorem gives weak convergence of ensemble members, and L p bounds on the ensemble then give L p convergence

The Earth of the Modern

One of the central questions in comparative studies of colonialism is what makes more recent variants of imperial extension so culturally distinctive, aside from the more obvious political-economic dimensions? This set of papers focuses on how European and Euro-American promulgated variants of colonialism can be viewed as embodying central tenets of modernism, such as progressivism, technocentrism, and hybridity. Moreover, the authors demonstrate how colonial practices in the era of the modern were not merely the result of policies emanating from imperial capitals, but were an outgrowth of conflict, mediation, and accommodation between colonizer and colonized. Thus, archaeological research is important for stressing that the past five centuries have seen a time of contested modernities, rather than the growth of \u27a\u27 modernist sensibility