2,482 research outputs found
Weighted ergodic theorems for Banach-Kantorovich lattice
In the present paper we prove weighted ergodic theorems and multiparameter
weighted ergodic theorems for positive contractions acting on
. Our main tool is the use of methods of
measurable bundles of Banach-Kantorovich lattices.Comment: 11 page
Dynamics of waves in 1D electron systems: Density oscillations driven by population inversion
We explore dynamics of a density pulse induced by a local quench in a
one-dimensional electron system. The spectral curvature leads to an "overturn"
(population inversion) of the wave. We show that beyond this time the density
profile develops strong oscillations with a period much larger than the Fermi
wave length. The effect is studied first for the case of free fermions by means
of direct quantum simulations and via semiclassical analysis of the evolution
of Wigner function. We demonstrate then that the period of oscillations is
correctly reproduced by a hydrodynamic theory with an appropriate dispersive
term. Finally, we explore the effect of different types of electron-electron
interaction on the phenomenon. We show that sufficiently strong interaction
[ where is the fermionic mass and the relevant spatial
scale] determines the dominant dispersive term in the hydrodynamic equations.
Hydrodynamic theory reveals crucial dependence of the density evolution on the
relative sign of the interaction and the density perturbation.Comment: 20 pages, 13 figure
Generalized Bayesian Record Linkage and Regression with Exact Error Propagation
Record linkage (de-duplication or entity resolution) is the process of
merging noisy databases to remove duplicate entities. While record linkage
removes duplicate entities from such databases, the downstream task is any
inferential, predictive, or post-linkage task on the linked data. One goal of
the downstream task is obtaining a larger reference data set, allowing one to
perform more accurate statistical analyses. In addition, there is inherent
record linkage uncertainty passed to the downstream task. Motivated by the
above, we propose a generalized Bayesian record linkage method and consider
multiple regression analysis as the downstream task. Records are linked via a
random partition model, which allows for a wide class to be considered. In
addition, we jointly model the record linkage and downstream task, which allows
one to account for the record linkage uncertainty exactly. Moreover, one is
able to generate a feedback propagation mechanism of the information from the
proposed Bayesian record linkage model into the downstream task. This feedback
effect is essential to eliminate potential biases that can jeopardize resulting
downstream task. We apply our methodology to multiple linear regression, and
illustrate empirically that the "feedback effect" is able to improve the
performance of record linkage.Comment: 18 pages, 5 figure
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