1,490 research outputs found
Unbiased and Consistent Nested Sampling via Sequential Monte Carlo
We introduce a new class of sequential Monte Carlo methods called Nested
Sampling via Sequential Monte Carlo (NS-SMC), which reframes the Nested
Sampling method of Skilling (2006) in terms of sequential Monte Carlo
techniques. This new framework allows convergence results to be obtained in the
setting when Markov chain Monte Carlo (MCMC) is used to produce new samples. An
additional benefit is that marginal likelihood estimates are unbiased. In
contrast to NS, the analysis of NS-SMC does not require the (unrealistic)
assumption that the simulated samples be independent. As the original NS
algorithm is a special case of NS-SMC, this provides insights as to why NS
seems to produce accurate estimates despite a typical violation of its
assumptions. For applications of NS-SMC, we give advice on tuning MCMC kernels
in an automated manner via a preliminary pilot run, and present a new method
for appropriately choosing the number of MCMC repeats at each iteration.
Finally, a numerical study is conducted where the performance of NS-SMC and
temperature-annealed SMC is compared on several challenging and realistic
problems. MATLAB code for our experiments is made available at
https://github.com/LeahPrice/SMC-NS .Comment: 45 pages, some minor typographical errors fixed since last versio
Impact and Concerns Related to Electronic Records Management and Storage
Electronic document or records management systems have been around for several decades. New technologies have evolved in recent years that provide new and expanded opportunities for organizations to use this electronically stored information in new ways. These storage technologies have also increased the number of real and potential problems, both short and long term, for technology managers. The purpose of this paper is to provide a brief outline of some research in process being done by the authors in the area of electronic document management and to invoke suggestions from other researchers
amei: An R Package for the Adaptive Management of Epidemiological Interventions
The amei package for R is a tool that provides a flexible statistical framework for generating optimal epidemiological interventions that are designed to minimize the total expected cost of an emerging epidemic. Uncertainty regarding the underlying disease parameters is propagated through to the decision process via Bayesian posterior inference. The strategies produced through this framework are adaptive: vaccination schedules are iteratively adjusted to reflect the anticipated trajectory of the epidemic given the current population state and updated parameter estimates. This document briefly covers the background and methodology underpinning the implementation provided by the package and contains extensive examples showing the functions and methods in action.
Laboratory Rearing of \u3ci\u3eLycaeides Melissa Samuelis\u3c/i\u3e (Lepidoptera: Lycaenidae), An Endangered Butterfly in Michigan
The Karner blue butterfly (Lycaeides melissa samuelis) is listed as a federally endangered species in the United States. It occurs in oak savanna and pine barren habitats from eastern Minnesota to New Hampshire. In 1994, we successfully reared Karner blue larvae under controlled laboratory conditions for experimental purposes, and report on those rearing methods here. We collected 20 female Karner blue adults of the spring generation from two areas in Michigan, and housed them in cages in an environmental chamber at 240 -26Ā°C for 5 days. The female butterflies produced 154 eggs, of which 72 hatched in an average of 4.5 days, and 68 first instars survived. Eggs, larvae and pupae were kept in a growth chamber at 24Ā°C. Developmental time from egg to adult averaged 26 days; the average duration of each instar ranged from 3 to 4 days, and the average pupal duration was 8 days. Thirty three lab- oratory-reared Karner blue larvae successfully completed the 4 instars, and were released as adults into maternal collection sites. Laboratory rearing may be a viable means of providing Karner blue individuals for reintroduction into areas where the species is extirpated, for supplementation of small populations, or for research. Ultimately, such methods may become an integral part in the recovery of this and other rare invertebrate species
Program Review--Intentional Harmony: Managing Work and Life
Intentional Harmony: Balancing Work and Life, a program developed by the University of Illinois Cooperative Extension, is designed to address the effects of work stress on the employee, partnerships, parenting, friend and family relationships, and personal health. The program is comprehensive, concise, and research-based. There is some empirical evidence of the effectiveness of the parenting unit. Additional research with random assignment of participants to experimental and control groups is recommended. An evaluation instrument is provided
Addressing Students\u27 Anxiety Levels in a High School Mathematics Classroom
In our ever-changing world, the use of technology is at all-time high. With the advent of our new technologies come new jobs and opportunities based on an education in mathematics and science. Now, more than ever we should be seeing an increase of students who enter college with a degree focused in these areas. Instead we are seeing little growth in these fields and anxiety is to blame.
This self-study was conducted to understand the ways in which: assessment, goal setting, teaching style, and technology affect studentās anxiety levels in mathematics. The study was conducted in an urban high school. Questionnaires, teacher journals, and lesson plans were analyzed. Students were asked to rate their anxiety levels during different classroom activities. Students were also asked what type of teaching styles, goals, technology use and assessments raised or lowered their anxiety levels. Several of these items were found to affect students anxiety levels in varying ways
Review of Fathers Reading Every Day (FRED): Leader\u27s Guide
There is a growing need for science-based, effective programs that enhance child-father relationships. This article reviews Fathers Reading Every Day (FRED): Leader\u27s Guide. The authors found FRED to be clearly research-based, to address the need to improve father-child relationships, to have limited empirical evidence of program effectiveness, and to be ready for busy Cooperative Extension agents and other professionals to use. It is recommended that further pretest-posttest, experimental-control group studies be conducted on its effectiveness
Exploratory Survey for the Emerald Ash Borer, \u3ci\u3eAgrilus Planipennis\u3c/i\u3e (Coleoptera: Buprestidae), and Its Natural Enemies in China
An exploratory survey for the emerald ash borer, Agrilus planipennis, and its natural enemies was conducted in China during October and November 2003. We examined 29 field plots in six provinces. We visually inspected living Fraxinus chinensis, F. mandshurica, F. pennsylvanica, F. rhynchophylla, and F. velutina then peeled off the bark in search of A. planipennis and associated natural enemies. We found active A. planipennis infestations in nine of the 29 field plots, including plots in the provinces of Hebei, Heilongjiang, Jilin, Liaoning, and the provincial level city of Tianjin. Signs of past A. planipennis infestations were found in five of the 20 plots where no active infestations were present. The distribution of A. planipennis was patchy within the forest, and larval densities varied greatly among trees and at different heights within the same tree. Agrilus planipennis densities ranged from 0 to 284 larvae/m2 of bark surface for 1-m log sections. The Nearctic ash species, F. pennsylvanica and F. velutina, planted in China were apparently more susceptible to A. planipennis attack than were the native Chinese ash species. Similarly, ash trees growing along streets or in plantations or city parks were more susceptible to A. planipennis infestation compared with trees in natural forests. We identified two species of natural enemies attacking A. planipennis during this survey. In Changchun City, Jilin Province and Guangang District, Tianjin City, we found a previously reported but undescribed species of Spathius sp. (Braconidae) parasitizing an average of 6.3% A. planipennis larvae in individual trees, ranging from 0 to 50%. In Changchun City, Jilin Province and in Benxi County, Liaoning Province, we discovered a previously unknown gregarious endoparasitoid of A. planipennis larvae, Tetrastichus nov. sp. (Eulophidae), with a total parasitism rate of 6.6% in individual trees, ranging from 0 to 50%. We discussed the potential role of natural enemies in the management of A. planipennis in North America
The Origins of Doha Project : Online Digital Heritage Remediation and Public Outreach in a Vanishing Pearling Town in the Arabian Gulf
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