Selection models with monotone weight functions in meta analysis

Publication bias, the fact that studies identified for inclusion in a meta analysis do not represent all studies on the topic of interest, is commonly recognized as a threat to the validity of the results of a meta analysis. One way to explicitly model publication bias is via selection models or weighted probability distributions. We adopt the nonparametric approach initially introduced by Dear (1992) but impose that the weight function $w$ is monotonely non-increasing as a function of the $p$-value. Since in meta analysis one typically only has few studies or "observations", regularization of the estimation problem seems sensible. In addition, virtually all parametric weight functions proposed so far in the literature are in fact decreasing. We discuss how to estimate a decreasing weight function in the above model and illustrate the new methodology on two well-known examples. The new approach potentially offers more insight in the selection process than other methods and is more flexible than parametric approaches. Some basic properties of the log-likelihood function and computation of a $p$-value quantifying the evidence against the null hypothesis of a constant weight function are indicated. In addition, we provide an approximate selection bias adjusted profile likelihood confidence interval for the treatment effect. The corresponding software and the datasets used to illustrate it are provided as the R package selectMeta. This enables full reproducibility of the results in this paper.Comment: 15 pages, 2 figures. Some minor changes according to reviewer comment

Dynamic facilitation explains democratic particle motion of metabasin transitions

Transitions between metabasins in supercooled liquids seem to occur through rapid "democratic" collective particle rearrangements. Here we show that this apparent homogeneous particle motion is a direct consequence of dynamic facilitation. We do so by studying metabasin transitions in facilitated spin models and constrained lattice gases. We find that metabasin transitions occur through a sequence of locally facilitated events taking place over a relatively short time frame. When observed on small enough spatial windows these events appear sudden and homogeneous. Our results indicate that metabasin transitions are essentially "non-democratic" in origin and yet another manifestation of dynamical heterogeneity in glass formers.Comment: 6 pages, 6 figure

Potential Biomass Yields in the South Central US

This paper describes research to create a national database of switchgrass supply as part of the biomass program launched by the Department of Energy. The paper provides an estimate of county level switchgrass yield data for the state of Oklahoma. The estimates are made for the top five most productive and abundant soils for each county in Oklahoma. A simple approach of ratio calculation and estimation is used to predict the switchgrass yield of one soil type by comparing it with the yield of several other crops in another soil type. The data for switchgrass yield for a particular soil type are obtained from the state research experiment stations. The yields for other crops for the top five soils are obtained from the NASS data sources. Switchgrass supply for Oklahoma was estimated to be 49.5 million tons from the top soils with the Northeast crop reporting district to be the dominant supplier.Biofuel, Switchgrass, Ratio Estimation, South Central, Oklahoma, Agricultural and Food Policy, Crop Production/Industries, Environmental Economics and Policy, Production Economics, Productivity Analysis, Research and Development/Tech Change/Emerging Technologies, Resource /Energy Economics and Policy,

Multi-kilowatt modularized spacecraft power processing system development

A review of existing information pertaining to spacecraft power processing systems and equipment was accomplished with a view towards applicability to the modularization of multi-kilowatt power processors. Power requirements for future spacecraft were determined from the NASA mission model-shuttle systems payload data study which provided the limits for modular power equipment capabilities. Three power processing systems were compared to evaluation criteria to select the system best suited for modularity. The shunt regulated direct energy transfer system was selected by this analysis for a conceptual design effort which produced equipment specifications, schematics, envelope drawings, and power module configurations

Disaster Assistance for U.S. Farmers: An Overview of the Current Debate and Two Proposals

The U.S. drought of 1988 has again focused attention on federal assistance to farm operators affected by natural disasters. Disaster aid to farmers, which currently includes subsidized crop insurance, emergency loans, and direct payments, has been a significant claimant on federal outlays since the mid-1970s. Its cost has generated on-going national debate and continuous pol icy experimentation. Genealogy of this debate is explored in this article, and two proposals are advanced

Disaster Assistance for U.S. Farmers: An Overview of the Current Debate and Two Proposals

The U.S. drought of 1988 has focused attention on federal assistance to farmers affected by drought and other natural disasters. However, disaster aid for farm operators has been a significant claimant on federal outlays since the mid-1970s. Current aid programs include emergency loans, direct payments, and subsidized crop insurance. Historically, cost of this assistance has been viewed as unacceptably high, resulting in continuous national debate and associated policy experimentation. Genealogy of this debate is explored, and two proposals are advanced

Matrix elements of atomic interaction operators for d sup n configurations

Tabulation of matrix elements of atomic interaction operators for various configuration

Modeling the amplification dynamics of human Alu retrotransposons

Journal ArticleRetrotransposons have had a considerable impact on the overall architecture of the human genome. Currently, there are three lineages of retrotransposons (Alu, L1, and SVA) that are believed to be actively replicating in humans. While estimates of their copy number, sequence diversity, and levels of insertion polymorphism can readily be obtained from existing genomic sequence data and population sampling, a detailed understanding of the temporal pattern of retrotransposon amplification remains elusive

Nest Hatch Chronology of Northern Bobwhite and Implications for Management

Managers in Missouri, USA, and in other Midwestern states have long operated under the belief that the peak of nest hatching for northern bobwhite (Colinus virginianus; hereafter, bobwhite) is 15 June. Though it is widely understood that bobwhite nests hatch throughout the summer, many management decisions are made based on the accepted peak. Fully understanding the dynamics behind bobwhite nest timing is critical, as management activities in nesting cover during summer are common. To better understand nest chronology, we used radio-telemetry to monitor nest incubation initiation, hatch date, and renesting rate on 6 conservation areas in southwestern Missouri from 2014 to 2018. Nest hatch date varied by area and year, but only 8.5% of nests hatched on or before 15 June. The 7-day interval during which the most nests hatched was 15–21 June, but we also saw high numbers of nests hatch in early July and mid- to late August. The median hatch date across all 5 years of the study was 17 July. Our results suggest that the entire summer is critical for bobwhite nesting activities, with late summer being just as important as the early summer months. We encourage bobwhite managers and conservation program policymakers across the Midwest to rethink previously held constructs of bobwhite nest timing. We also recommend that summer disturbances to nesting cover be kept to a minimum when the goal is to maximize bobwhite reproductive output