Mixture of normals probit models

This paper generalizes the normal probit model of dichotomous choice by introducing mixtures of normals distributions for the disturbance term. By mixing on both the mean and variance parameters and by increasing the number of distributions in the mixture these models effectively remove the normality assumption and are much closer to semiparametric models. When a Bayesian approach is taken, there is an exact finite-sample distribution theory for the choice probability conditional on the covariates. The paper uses artificial data to show how posterior odds ratios can discriminate between normal and nonnormal distributions in probit models. The method is also applied to female labor force participation decisions in a sample with 1,555 observations from the PSID. In this application, Bayes factors strongly favor mixture of normals probit models over the conventional probit model, and the most favored models have mixtures of four normal distributions for the disturbance term.Econometric models

Herschel evidence for disk flattening or gas depletion in transitional disks

Transitional disks are protoplanetary disks characterized by reduced near- and mid-infrared emission with respect to full disks. This characteristic spectral energy distribution indicates the presence of an optically thin inner cavity within the dust disk believed to mark the disappearance of the primordial massive disk. We present new Herschel Space Observatory PACS spectra of [OI] 63 micron for 21 transitional disks. Our survey complements the larger Herschel GASPS program "Gas in Protoplanetary Systems" (Dent et al. 2013) by quadrupling the number of transitional disks observed with PACS at this wavelength. [OI] 63 micron traces material in the outer regions of the disk, beyond the inner cavity of most transitional disks. We find that transitional disks have [OI] 63 micron line luminosities two times fainter than their full disk counterparts. We self consistently determine various stellar properties (e.g. bolometric luminosity, FUV excess, etc.) and disk properties (e.g. disk dust mass, etc.) that could influence the [OI] 63 micron line luminosity and we find no correlations that can explain the lower [OI] 63 micron line luminosities in transitional disks. Using a grid of thermo-chemical protoplanetary disk models, we conclude that either transitional disks are less flared than full disks or they possess lower gas-to-dust ratios due to a depletion of gas mass. This result suggests that transitional disks are more evolved than their full disk counterparts, possibly even at large radii.Comment: Accepted for publication in ApJ; 52 pages, 16 figures, 8 table

Effects of Supplementary Concentrate Level and Separate or Mixed Feeding of Grass Silage and Concentrates on Rumen Fluid Composition in Steers

The effects of dietary concentrate level and method of feeding (separate or mixed) on performance and carcass traits of steers may be mediated through changes in rumen fluid composition. The objectives of this study were to determine the effects on rumen fluid composition of (1) supplementary concentrate level with grass silage, and (2) separate or mixed feeding of silage and concentrates

Effects of Supplementary Concentrate Level and Separate or Mixed Feeding of Grass Silage and Concentrates on Carcass Tissue Composition in Steers

Supplementary concentrate level may affect carcass composition in steers. Feeder wagons facilitate feeding and management. The objectives were to determine the effects of (1) supplementary concentrate level with grass silage, and (2) separate or mixed feeding of silage and concentrates, on ribs joint composition

Intensity of Vascular Streak Dieback in Different Cocoa Clones and Various Agro-climatic Conditions

Vascular streak dieback (VSD) is one of the main diseases on cocoa. This disease can produce a heavy damage in susceptible plants. Agro-climatic condition influences the VSD disease severity level. A study on the relationship between agro-climatic condition and VSD disease severity was conducted in eight locations which were selected based on difference in agro-climatic conditions including altitude, rainfall, number of wet, and dry months. Randomized complete block design was used consisting of eight agro-climatic conditions as treatments which consisted of 200 trees samples, and scored for VSD intensity. A study was also conducted on the response of cocoa clones with different level of resistance at different altitude at Kendeng Lembu, Jatirono, Sungai Lembu, Banjarsari, and Sumber Asin Plantations. A split plot design was applied consisting of two factors. The first factor was location including Pager Gunung (highland) and Besaran (lowland). The second factor was clone resistance with two levels: PA 191 (resistant) and BL 703 (susceptible). VSD scores and stomatal characteristics (stomata number, stomata diameter, and stomata aperture) were determined. The results of experiment showed that VSD scoring differed significantly between the eight agro-climatic conditions. The highest VSD score occurred in the lowland (Gereng Rejo, Banjarsari Plantation, 38 m asl.), where the average annual rainfall was 2161 mm, with five dry months. Cocoa trees in Sumber Asin (580 m asl.), with the average annual rainfall of 2302 mm and 8.5 wet months/3.5 dry months were mostly free of VSD disease. Altitude was positively correlated with rainfall, and negatively correlated with VSD severity. Number of wet months was negatively correlated with VSD severity. Conversely, number of dry months was positively correlated with VSD. The result indicated that genotype, environment, or their interaction did not significantly affect number and aperture of stomata. Although stomatal diameter was significantly affected by environment, genotypes or their interaction with environment did not influence this character

French responses to the Prague Spring: connections, (mis)perception and appropriation

Looking at the vast literature on the events of 1968 in various European countries, it is striking that the histories of '1968' of the Western and Eastern halves of the continent are largely still written separately.1 Nevertheless, despite the very different political and socio-economic contexts, the protest movements on both sides of the Iron Curtain shared a number of characteristics. The 1968 events in Czechoslovakia and Western Europe were, reduced to the basics, investigations into the possibility of marrying social justice with liberty, and thus reflected a tension within European Marxism. This essay provides an analysis specifically of the responses by the French left—the Communist Party, the student movements and the gauchistes—to the Prague Spring, characterised by misunderstandings and strategic appropriation. The Prague Spring was seen by both the reformist and the radical left in France as a moderate movement. This limited interpretation of the Prague Spring as a liberal democratic project continues to inform our memory of it

Effects of Supplementary Concentrate Level and Separate or Mixed Feeding of Grass Silage and Concentrates on Carcass Tissue Colour Traits in Steers

The level of supplementary concentrates fed with grass silage and the method of feeding (separate or mixed) may affect carcass tissue colour in steers. The objectives were to determine the effects of (1) supplementary concentrate level with grass silage, and (2) separate or mixed feeding of silage and concentrates, on muscle and fat colour