69 research outputs found
Asymptotic inference for high-dimensional data
In this paper, we study inference for high-dimensional data characterized by
small sample sizes relative to the dimension of the data. In particular, we
provide an infinite-dimensional framework to study statistical models that
involve situations in which (i) the number of parameters increase with the
sample size (that is, allowed to be random) and (ii) there is a possibility of
missing data. Under a variety of tail conditions on the components of the data,
we provide precise conditions for the joint consistency of the estimators of
the mean. In the process, we clarify and improve some of the recent consistency
results that appeared in the literature. An important aspect of the work
presented is the development of asymptotic normality results for these models.
As a consequence, we construct different test statistics for one-sample and
two-sample problems concerning the mean vector and obtain their asymptotic
distributions as a corollary of the infinite-dimensional results. Finally, we
use these theoretical results to develop an asymptotically justifiable
methodology for data analyses. Simulation results presented here describe
situations where the methodology can be successfully applied. They also
evaluate its robustness under a variety of conditions, some of which are
substantially different from the technical conditions. Comparisons to other
methods used in the literature are provided. Analyses of real-life data is also
included.Comment: Published in at http://dx.doi.org/10.1214/09-AOS718 the Annals of
Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical
Statistics (http://www.imstat.org
Corrections and acknowledgment for ``Local limit theory and large deviations for supercritical branching processes''
Corrections and acknowledgment for ``Local limit theory and large deviations
for supercritical branching processes'' [math.PR/0407059]Comment: Published at http://dx.doi.org/10.1214/105051606000000574 in the
Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute
of Mathematical Statistics (http://www.imstat.org
Local limit theory and large deviations for supercritical Branching processes
In this paper we study several aspects of the growth of a supercritical
Galton-Watson process {Z_n:n\ge1}, and bring out some criticality phenomena
determined by the Schroder constant. We develop the local limit theory of Z_n,
that is, the behavior of P(Z_n=v_n) as v_n\nearrow \infty, and use this to
study conditional large deviations of {Y_{Z_n}:n\ge1}, where Y_n satisfies an
LDP, particularly of {Z_n^{-1}Z_{n+1}:n\ge1} conditioned on Z_n\ge v_n
Large deviation results for branching processes in fixed and random environments
This thesis considers three different aspects of large deviations for branching processes. First, we study the deviation between the empirical mean and the true mean. Second, we investigate the large deviation behavior exhibited by the tail of the random variable W occurring in multi-type branching processes. Finally, we discuss the large deviations as they apply to a branching random walk in stationary ergodic environments
Effect of diethylstilbesterol and prolactin on the induction of follicle stimulating hormone receptors in immature and cycling rats
Induction of follicle stimulating hormone receptor in the granulosa cells of intact immature rat ovary by diethylstilbesterol, an estrogen, has been studied. A single injection of 4 mg of diethylstilbesterol produced 72 h later a 3-fold increase in follicle stimulating hormone receptor concentration as monitored by [125I]-oFSH binding to isolated cells. The newly induced receptors were kinetically indistinguishable from the preexisting ones, as determined by Lineweaver-Burk plot of the binding data. The induced receptors were functional as evidenced by increased ability of the granulosa cells to incorporate [3H]-leucine into cellular proteins. Neutralization of endogenous follicle stimulating hormone and luteinizing hormone by administering specific antisera had no effect on the ability of diethylstilbesterol to induce follicle stimulating hormone receptors, whereas blockade of endogenous prolactin secretion by ergobromocryptin administration significantly inhibited (~ 30 %) the response to diethylstilbesterol; this inhibition could be completely relieved by ovine prolactin treatment. However, ovine prolactin at the dose tried did not by itself enhance follicle stimulating hormone receptor level. Administration of ergobromocryptin to adult cycling rats at noon of proestrus brought about as measured on diestrusII, (a) a reduction of both follicle stimulating hormone (~ 30 %) and luteinizing hormone (~ 45 %) receptor concentration in granulosa cells, (b) a drastic reduction in the ovarian tissue estradiol with no change in tissue progesterone and (c) reduction in the ability of isolated granulosa cells to convert testosterone to estradiol in response to follicle stimulating hormone. Ergobromocryptin treatment affected only prolactin and not follicle stimulating hormone or luteinizing hormone surges on the proestrus evening. Treatment of rats with ergobromocryptin at proestrus noon followed by an injection of ovine prolactin (1 mg) at 1700 h of the same day completely reversed the ergobromocryptin induced reduction in ovarian tissue estradiol as well as the aromatase activity of the granulosa cells on diestrus II, thus suggesting a role for proestrus prolactin surge in the follicular maturation process
Functional limit laws for the intensity measure of point processes and applications
Motivated by applications to the study of depth functions for tree-indexed
random variables generated by point processes, we describe functional limit
theorems for the intensity measure of point processes. Specifically, we
establish uniform laws of large numbers and uniform central limit theorems over
a class of bounded measurable functions for estimates of the intensity measure.
Using these results, we derive the uniform asymptotic properties of half-space
depth and, as corollaries, obtain the asymptotic behavior of medians and other
quantiles of the standardized intensity measure. Additionally, we obtain
uniform concentration upper bound for the estimator of half-space depth. As a
consequence of our results, we also derive uniform consistency and uniform
asymptotic normality of Lotka-Nagaev and Harris-type estimators for the Laplace
transform of the point processes in a branching random walk.Comment: 38 page
- …