Asymptotically minimax Bayes predictive densities

Given a random sample from a distribution with density function that depends on an unknown parameter $\theta$, we are interested in accurately estimating the true parametric density function at a future observation from the same distribution. The asymptotic risk of Bayes predictive density estimates with Kullback--Leibler loss function $D(f_{\theta}||{\hat{f}})=\int{f_{\theta} \log{(f_{\theta}/ hat{f})}}$ is used to examine various ways of choosing prior distributions; the principal type of choice studied is minimax. We seek asymptotically least favorable predictive densities for which the corresponding asymptotic risk is minimax. A result resembling Stein's paradox for estimating normal means by the maximum likelihood holds for the uniform prior in the multivariate location family case: when the dimensionality of the model is at least three, the Jeffreys prior is minimax, though inadmissible. The Jeffreys prior is both admissible and minimax for one- and two-dimensional location problems.Comment: Published at http://dx.doi.org/10.1214/009053606000000885 in the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org

Effect of vetch wheat mixture and broccoli as preceding crops on organic summer vegetables: on farm trial in western Turkey

Organic farming requires the use of practices such as crop rotation, green manure and compost application instead of chemical compounds to enhance farm productivity. In this study, effects of two pre-crops (vetch-wheat mixture and broccoli) and additional fertilization (AF) strategy (compost and commercial fertilizer) were tested on organic production of two main crops (tomato and zucchini) and on soil fertility. The main aim of this on-farm trial is to evaluate the applicability of the results obtained over four years study under experimental conditions. Pre-crops and AF strategy had no significant effect on zucchini yield; highest tomato yield was recorded after vetch-wheat mixture and AF. At the end of the cycle soil organic matter statistically increased in vetch-wheat mixture with AF plots. Soil nitrogen (N) levels increased slightly in all treatments but this increase was not significantly different from the initial level of N. Vetch-wheat mixture and tomato rotation with AF provided the highest gross-margin due to a higher yield

Examination of parental and special education teachers' attitudes towards sports activities of students with intellectual disability

The purpose of this study was to examine the attitudes of parents of students with intellectual disability and special education teachers working in special education schools to the sports activities of students with intellectual disability (ID).The study included 92 volunteer teachers who worked in special education schools, and 116 voluntary parents of children with ID who attended special education schools. The "Attitude Towards Sports Activities of Intellectually Disabled Individuals Scale" was used by participants to determine their attitudes towards the participation of students with intellectual disabilities. The total scale scores of the teachers and the parents were 100.39 ± 9.41 and 117.00 ± 15.47, respectively. When the scale scores of the teachers and the parents were compared, there was a statistically significant difference in favor of the parents (p = 0.000). The results of this study have shown that special education teachers and parents of students with intellectual disabilities have positive attitudes towards their participation in sports activities. The attitudes of the parents were found to be more positive than those of the special special education teachers. © 2018 by authors, all rights reserved

X-ray detector on 2U cubesat BeEagleSAT of QB50

BeEagleSAT is a 2 Unit cubesat to be launched within the EU FP7 project QB 50. It is been produced by Istanbul Technical University and Turkish Air Force Academy. Sabanci University will provide a CdZnTe based semiconductor X-ray detector and associated readout electronics. The detector will utilize cross strip geometry to test the detection system in space, but it will not carry a mask for imaging. The readout will be established by an application specific integrated circuit controlled by a microcontroller. The system will have its own battery and will be turned on intermittently due to power and telemetry constraints. It will characterize the hard X-ray background in 20-150 keV at low Earth orbit conditions as a function of altitude

Ethnic Disparities in Degree Performance

Using unique administrative individual data, this paper examines ethnic differences in degree performance in Dutch colleges and universities. The paper estimates parametric duration models and accounts for unobserved heterogeneity to assess the sources of ethnic disparities. The analysis shows that ethnic minorities from non-western countries have a significantly lower degree performance and higher risk of dropping-out. Especially, Turkish, Moroccan and Caribbean students are less likely to graduate, and graduates among them need much more time to complete their study. There is no evidence that this disadvantage stems from poor parental socioeconomic position and the choice of study subject.tertiary education, drop-out

WP 64 - Struggling for a proper job: recent immigrants in the Netherlands

This article concerns the employment performance of recent immigrants in the Netherlands. The analysis shows different patterns of adjustment in the Dutch labour market for Western and non-Western immigrants. The entry of Western immigrants into the labour market follows a smooth pattern, while non-Western immigrants have relatively low employment and relatively high unemployment upon arrival. In addition, they often start with semi-skilled or unskilled jobs. The labour market position of non-Western immigrants improves significantly over time. However, a considerable proportion of the disadvantages remains and seems to be persistent over time. Among non-Western immigrants, especially the Turks and Moroccans seem to face difficulties in the labour market, while the Surinamese and Antilleans are able to compensate for a large part of their substantial initial disadvantage. The relative success of the last group is probably a result of their familiarity with Dutch society.Immigrants, Employment, Unemployment, Quality of jobs JEL Classification: J15, J21, J24

The validity of PPP: evidence from Lagrange multiplier unit root tests for ASEAN countries

The univariate and panel Lagrange Multiplier (LM) unit root tests with one and two structural breaks proposed by Lee and Strazicich (2003, 2004) which are considerably more powerful than traditional tests are employed to investigate whether the purchasing power parity (PPP) theory holds true for ASEAN countries by using both black market and official exchange rates. We find strong evidence in favour of long-run PPP for six ASEAN countries namely, Indonesia, Malaysia, Myanmar, Philippines, Singapore and Thailand.PPP,ASEAN,LM unit root

Convergence of per capita health care expenditures in OECD Countries

In this article it is investigated the convergence of health care expenditures per capita in OECD during the 1970–2005 period by applying Lima and Resende (2007) persistence methodology. Departures across countries were evaluated in terms of panel data unit root tests advanced by Im et al. (2003). The evidence illustrated that one cannot reject the null hypothesis of unit root for the (log) of the ratio of health care expenditures of each country relative to a reference unit except average of per capita health expenditures The results, therefore, favour a very strong form of persistence for OECD expenditures inequality.

Immigrant Participation in Welfare Benefits in the Netherlands

The efficiency of Dutch welfare system is at the heart of debate as long as immigrants are overrepresented in social welfare benefits during the working age period. This paper examines the degree of participation in social assistance, disability and unemployment benefits across ethnic groups using register data of the entire population in the Netherlands. The analysis shows that migrants are drastically more likely to have a benefit, in particular social assistance and disability benefits. A large part of migrants' dependence can be explained by their background characteristics and immigration history but still a significant unexplained residual is left. Most notably, the probability of welfare use of non-western second generation is about twice as high as the probability of western immigrants, which is a true challenge for policy makers.ethnic minorities, benefits, inactivity