13 research outputs found
On the frequentist coverage of Bayesian credible intervals for lower bounded means
For estimating a lower bounded location or mean parameter for a symmetric and
logconcave density, we investigate the frequentist performance of the
Bayesian HPD credible set associated with priors which are
truncations of flat priors onto the restricted parameter space. Various new
properties are obtained. Namely, we identify precisely where the minimum
coverage is obtained and we show that this minimum coverage is bounded between
and ; with
the lower bound improving (for ) on the
previously established ([9]; [8]) lower bound .
Several illustrative examples are given.Comment: Published in at http://dx.doi.org/10.1214/08-EJS292 the Electronic
Journal of Statistics (http://www.i-journals.org/ejs/) by the Institute of
Mathematical Statistics (http://www.imstat.org
ChromoShake: a chromosome dynamics simulator reveals that chromatin loops stiffen centromeric chromatin
ChromoShake is a three-dimensional simulator designed to find the thermodynamically favored states for given chromosome geometries. The simulator has been applied to a geometric model based on experimentally determined positions and fluctuations of DNA and the distribution of cohesin and condensin in the budding yeast centromere. Simulations of chromatin in differing initial configurations reveal novel principles for understanding the structure and function of a eukaryotic centromere. The entropic position of DNA loops mirrors their experimental position, consistent with their radial displacement from the spindle axis. The barrel-like distribution of cohesin complexes surrounding the central spindle in metaphase is a consequence of the size of the DNA loops within the pericentromere to which cohesin is bound. Linkage between DNA loops of different centromeres is requisite to recapitulate experimentally determined correlations in DNA motion. The consequences of radial loops and cohesin and condensin binding are to stiffen the DNA along the spindle axis, imparting an active function to the centromere in mitosis
Charge tunneling rates in ultrasmall junctions
1.1. Ultrasmall tunnel junctions With the advances of microfabrication techniques in recent years it has become possible to fabricate tunnel junctions of increasingly smaller dimensions and thereby decreasing capacitance C. Nowadays one can study tunnel junctions in a regime wher