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The objective of the study was to determine the membership probability and level of admixture among Slovak Spotted cattle and historically related breeds (Ayshire, Holstein, Swiss Simmental and Slovak Pinzgau). The analysis was based on the panel of 35 934 SNPs that were used for genotyping of 423 individuals. The optimal number of clusters was estimated in two ways; by analysis of Bayesian information criterion and Bayesian clustering algorithm. The optimal number of clusters ranged from 3 to 5, depending on the applied approach. Subsequently, the population structure was tested by discriminant analysis of principal components (DAPC) and unsupervised Bayesian analysis based on the correlated allele frequencies model. The first discriminant function revealed three genetic clusters in population resulting from the production type and origin of analysed breeds. The unsupervised Bayesian analysis showed similar results, where the highest level of admixture was found between Slovak Pinzgau and Slovak Spotted cattle (0.6%). Despite that, the results of this study clearly showed that the Slovak Spotted cattle is genetically separated from other breeds that were involved in its grading-up process.

Classifiers for a highly imbalanced dataset tend to bias in majority classes and, as a result, the minority class samples are usually misclassified as majority class. To overcome this, a proper undersampling technique that removes some majority samples can be an alternative. We propose an efficient and simple undersampling method for imbalanced datasets and show that the proposed method outperforms others with respect to four different performance measures by several illustrative experiments, especially for highly imbalanced datasets.

We report the discovery of VMC J021140.41-735320.4, a faint ($J=19.9$ mag) and extremely red ($J-K_s=3.0$ mag, $W1-W2=0.45$ mag, $J-W2=4.7$ mag) high proper motion object in front of the Magellanic Bridge region. It is even redder in the near-infrared than the reddest L7 dwarfs ($J-K_s \gtrsim 2.8$ mag) found in the survey of Schneider et al. (2017) and its colours do also not match exactly those of other peculiar red L7.5 dwarfs. Therefore, we consider its photometric distance estimate of about 73 pc as uncertain. A preliminary combined proper motion and parallax solution involving 20 epochs from the Visible and Infrared Survey Telescope for Astronomy (VISTA) survey of the Magellanic Clouds (VMC), the VISTA hemisphere survey (VHS), and the Wide-field Infrared Survey Explorer (WISE) yields $\mu_{\alpha}\cos{\delta}=+74.3\pm3.4$ mas/yr, $\mu_{\delta}=+22.3\pm3.4$ mas/yr, and $\pi=21.0\pm7.1$ mas. Applying the BANYAN tool (http://www.exoplanetes.umontreal.ca/banyan/) to these results we find a $\approx$68% membership probability of this object in the AB Doradus young moving group (YMG). With its trignometric distance of $\approx$48 pc, VMC J021140.41-735320.4 has a similar absolute magnitude of $M_{K_s}\approx13.4$ mag as the planetary mass companion of another AB Doradus YMG member candidate, 2MASS J22362452+4751425. Follow-up classification spectroscopy and astrometric monitoring are recommended., Comment: 2 pages, 1 figure, published in RNAAS (abstract not included in original paper)

We analyze the membership probability of young stars belonging to nearby moving groups with $\textit{Gaia}$ DR2 data. The sample of 1429 stars were identified from 'The Catalog of Suspected Nearby Young Moving Group Stars'. Good-quality parallax and proper motion values were retrieved for 890 stars from $\textit{Gaia}$ DR2 database. The analysis for membership probability is performed in the framework of LACEwING algorithm. From the analysis it is confirmed that 279 stars do not belong to any of the known moving groups. We estimated the $\textit{ U, V, W}$ space velocity values for 250 moving group members, which were found to be more accurate than previous values listed in the literature. The velocity ellipses of all the moving groups are well constrained within the "good box", a widely used criterion to identify moving group members. The age of moving group members are uniformly estimated from the analysis of $\textit{Gaia}$ Color-Magnitude Diagram with MIST isochrones. We found a spread in the age distribution of stars belonging to some moving groups, which needs to be understood from further studies., Comment: 14 Pages, 5 Figures, 4 Tables, Accepted for publication in AJ

This study shows the application of a system to monitor the state of damage of railway wheel steel specimens during rolling contact fatigue tests. This system can make continuous measurements with an evaluation of damage without stopping the tests and without destructive measurements. Four tests were carried out to train the system by recording torque and vibration data. Both statistical and spectral features were extracted from the sensors signals. A Principal Component Analysis (PCA) was performed to reduce the volume of the initial dataset, then, the data were classified with the k-means algorithm. The results were then converted into probabilities curves. Metallurgical investigations (optical micrographs, wear curves) and hardness tests were carried out to assess the trends of machine learning analysis. The training tests were used to train the proposed algorithm. Three validation tests were performed by using the real-time results of the k-means algorithm as a stop condition. Metallurgical analysis was performed also in this case. The validation tests follow the results of the training test and metallurgical analysis confirms the damage found with the machine learning analysis: when the membership probability of the cluster corresponding to the damage state reaches a value higher than 0.5, the metallurgical analysis clearly shows the cracks on the surface of the specimen due to the rolling contact fatigue (RCF) damage mechanism. These preliminary results are positive, even if reproduced on a limited set of specimens. This approach could be integrated in rolling contact fatigue tests to provide additional information on damage progression.

Nearby young moving groups provide unique samples of similar age stars for testing the evolution of physical properties. Incomplete and/or incorrect group membership classifications reduce the usefulness of the group, which we assume to be coeval. With near-infrared spectra of two candidate members of the TW Hya Association, 2MASS J12354615$-$4115531 (TWA 46) and 2MASS J12371238$-$4021480 (TWA 47), we test their membership by adding radial velocity measurements to the literature. We find that 2MASS J12354615$-$4115531 is a close spectroscopic binary system with a center-of-mass radial velocity of -6.5$\pm$3.9 km s$^{-1}$. This radial velocity and a $\textit{Gaia}$ parallax produces a TWA membership probability of 41.9$\%$ using the Banyan $\Sigma$ tool for 2MASS J12354615$-$4115531. The spectrum of 2MASS J12371238$-$4021480 shows that it appears to be a single star with a radial velocity consistent with the TW Hya Association and a membership probability of 99.5$\%$. The reduced probability of TWA 46 as a true member of TWA highlights the importance of high-resolution, near-infrared spectra in validating low-mass moving group members., Comment: 10 pages, 4 figures, 2 tables

Interstellar polarimetric data of the six open clusters Hogg 15, NGC 6611, NGC 5606, NGC 6231, NGC 5749 and NGC 6250 have been used to estimate the membership probability for the stars within them. For proper-motion member stars, the membership probability estimated using the polarimetric data is in good agreement with the proper-motion cluster membership probability. However, for proper-motion non-member stars, the membership probability estimated by the polarimetric method is in total disagreement with the proper-motion cluster membership probability. The inconsistencies in the determined memberships may be because of the fundamental differences between the two methods of determination: one is based on stellar proper-motion in space and the other is based on selective extinction of the stellar output by the asymmetric aligned dust grains present in the interstellar medium. The results and analysis suggest that the scatter of the Stokes vectors q(%) and u(%) for the proper-motion member stars depends on the interstellar and intra-cluster differential reddening in the open cluster. It is found that this method could be used to estimate the cluster membership probability if we have additional polarimetric and photometric information for a star to identify it as a probable member/non-member of a particular cluster, such as the maximum wavelength value (\lambda_max), the unit weight error of the fit (\sigma_1), the dispersion in the polarimetric position angles (\epsilon), reddening (E(B-V)) or the differential intra-cluster reddening (\Delta E(B-V)). This method could also be used to estimate the membership probability of known member stars having no membership probability as well as to resolve disagreements about membership among different proper-motion surveys., Comment: 11 pages, 3 figures, 5 tables, accepted for publication in MNRAS

Objective Common mental disorders are a major concern in working populations due to their high prevalence and as a barrier to remaining healthy and productive at work. Patients with common mental disorders often suffer from comorbidities, which may limit their functioning at work. We assessed the longitudinal impact of multimorbidity, defined as two or more co-occurring chronic health conditions, on work functioning among workers who had returned to work after sick leave due to a common mental disorder. Methods Prospective cohort study of 156 workers followed for one year after return to work from sick leave due to a common mental disorder. A multimorbidity score was computed by counting severity-weighted chronic health conditions measured at baseline. Work functioning was measured at baseline and at 3, 6 and 12 months follow-up with the Work Role Functioning Questionnaire. Work functioning trajectories were identified using latent class growth analysis to investigate the effect of multimorbidity on the course of work functioning scores. Results A total of 44% workers had multimorbidity. Four work functioning trajectories were identified: one (12% of the workers) showed increasing work functioning scores during follow-up, whereas the other three trajectories showed stable low, medium and high scores (23%, 41% and 25% workers, respectively). Multimorbidity did not predict membership probability in any trajectory. However, within the increasing score trajectory, levels of work functioning were lower among those with a high baseline multimorbidity score; each one unit increase in multimorbidity implied a reduction of 1.4 points in the work functioning score (p > 0.001). Conclusions Multimorbidity has a negative impact on workers’ perception of work functioning after returning to work from a sick leave due to a common mental disorder.

This paper investigates the spatial distribution of cattle breeders in Texas to quantify how climate factors influence cattle breed selection. A multivariate probit model is employed to examine the county-level binary choices of Bos taurus, Bos indicus and composite breeds derived from cattle breed association membership data. The estimation results suggest that summer heat stress is a significant factor for breed selection: positive for Bos indicus and negative for Bos taurus and composite breeds, with the average marginal effects on breed membership probability being 9.7 %, −26.5 % and −7.9 %, respectively. The intensity of the summer heat impacts can lead to noteworthy changes in spatial distributions of Texas cattle breeds in the event of climate change.

We present an analysis of the WISE photometric data for 829 stars in the Sco-Cen OB2 association, using the latest high-mass membership probabilities. We detect infrared excesses associated with 135 BAF-type stars, 99 of which are secure Sco-Cen members. There is a clear increase in excess fraction with membership probability, which can be fitted linearly. We infer that 41+-5% of Sco-Cen OB2 BAF stars to have excesses, while the field star excess fraction is consistent with zero. This is the first time that the probability of non-membership has been used in the calculation of excess fractions for young stars. We do not observe any significant change in excess fraction between the three subgroups. Within our sample, we have observed that B-type association members have a significantly smaller excess fraction than A and F-type association members.

We use new data from Gaia DR2 to confirm that the young L1 $\gamma$ candidate member of the TW Hya association (TWA) is now a bona fide member with a model-dependent mass estimate of ~15 $M_{Jup}$. The ambiguous M9 $\gamma$ candidate member 2MASS J12474428---3816464 also gets a higher Bayesian membership probability for TWA membership as a result of Gaia DR2 data and a new radial velocity measurement, but it remains unclear whether it is a true member of TWA or if it is an unrelated young interloper, because it is separated by 4.6 km/s from the locus of TWA members in UVW space.

Museum collections are often invaluable repositories of information for archaeologists, as they contain large numbers of intact, well provenanced objects. However, the utility of such collections for chemical analysis is often limited by the inability to perform destructive analysis on them. We report here on the analysis of Killke (ad 1000–1400) and Inka (ad 1400–1532) ceramics from the Cuzco area of Peru housed in the Field Museum of Natural History South American collections using a specially modified open-cell laser to generate compositional data from complete intact vessels in a minimally destructive manner. These data are compared to measurements performed using a conventional laser cell on Killke and Inka sherds from the same collections and regional raw material samples. We discuss both the utility and shortcomings of the open-cell system as a means of ceramic analysis, as well as implications for archaeological understanding of prehistoric ceramic production and economy in the Cuzco area.

Using deep exposures (~10^5 s) with the ROSAT HRI, we have performed flux-limited surveys for X-ray sources in the vicinity of the Hyades-age open stellar clusters NGC 6633 and IC 4756, detecting 31 and 13 sources respectively. Our primary aim is to search for so-far unrecognised cluster members. We propose identifications or classifications (cluster member, field star, extragalactic field object) for the X-ray sources, based on published membership lists, and on X-ray:optical flux ratios and optical colour--magnitude diagrams. Results of simulating the expected X-ray-emitting source populations are compared with the ROSAT measurements and with the expected capabilities of the XMM mission. The simulations provide a novel method of comparing the activity levels of NGC 6633 and IC 4756 with that of the Hyades. The measurements and simulations confirm that cluster members are the major class of X-ray emitter in these fields at flux levels f_x > 10^{-14}/erg/cm^2/s (0.1--2.4 keV), contributing ~40 per cent of the total X-ray sources. We find 6 possible new members in NGC 6633, and 4 candidates in IC 4756; all require further observation to establish membership probability.

We present mean absolute proper motions of 112 open clusters, determined using the data from the Tycho2 Catalogue. For 28 clusters, this is the rst determination of proper motion. The measurements made use of a large number of stars (usually several tens) for each cluster. The total number of stars studied in the elds of the 164 open clusters is 5016, of which 4006 were considered members. The mean proper motions of the clusters and membership probability of individual stars were obtained from the proper motion data by applying the statistical method proposed by Sanders (1971).

87 stars in the NGC 6913 field with both UBV and Vilnius photometry are selected to be the sample. The membership probability of the stars is greater than 50%. The correlation among Vilnius photometry, UBV photometry and reddening in the cluster is reviewed. It is found that the photometry in the Vilnius X, Y and Z bands can be used to make rough spectral classification. The values of E( B-V ) are well correlated with the Vilnius colors of X-Y, Y-Z, Z-V and V-S in NGC 6913. The ratio of ( V-S )/( Y-Z ) of the MPCM (Most Possible Cluster Members) is a constant (1.30 ∼ p0.06), and has no effect on the values of E( B-V ), ( B-V ) 0 and V 0 . Comparing with the observational data of all the stars of NGC 6913 region, we propose that the value of ( V-S )/( Y-Z ) can probably be used to select the preliminary candidates of one open cluster. In addition, 12 variable stars are discovered in the NGC 6913 region, in which star #155 has a variation with an amplitude of 4.25 mag.

The satellites MOST and CoRoT have observed the young open cluster NGC 2264 in 2006 and 2008, respectively. The resulting high-precision time-series photometry has been used to investigate the pulsational properties of pre-main sequence (PMS) cluster members. We present a highlight of this study.

Open clusters become a powerful astrophysics laboratory once the essential problem of stellar membership has been solved. In this paper different methods to compute membership probabilities using kinematical variables, mainly proper motions, are presented.

I review the current methods of extracting parameters from cluster colour-magnitude diagrams, and compare them with the requirements for extracting the new information available from the next generation of optical and infrared sky surveys. I conclude that the basic statistical tools are beginning to emerge, but that there are significant problems with optical pre-main-sequence isochrones which will severely limit our ability to determine parameters for pre-main-sequence populations. In addition we need better tools to use the information relating background and foreground contamination which the sky surveys will provide.

In this chapter, we formulate the probabilistic ranking queries on uncertain data. We first introduce two basic uncertain data models and basic probabilistic ranking queries. Then, we discuss three extended uncertain data models that suit different application scenarios. Ranking queries on the extended uncertain data models are also developed.

Astrometric cluster membership probabilities have been derived from proper motion of the open cluster NGC 2301. A comparison with previous investigations is presented.

Despite enormous effort put into the membership determination of M67, we do not know very well its peripheral members. Since the Bonn double astrograph as well as Pulkovo normal astrograph plates cover nearly 1.5 × 1.5 on the sky we have combined newly derived astrometric data from both instruments. Nearly 2,000 stars were measured down to the plate limit B ≈ 16.5. The proper-motion standard error for well-measured stars is ±0.3 mas/yr. For the membership probability solution we selected only 1363 stars, all brighter than V ≈ 15.0, with good proper motions. The membership solution yielded 446 cluster members showing convincing discrimination between the cluster and field stars. The spatial distribution of peripheral cluster members seems to be asymmetric, although, it does not indicate that the tidal radius of the cluster has been reached.

Stochastic logic is a nonstandard logic that essentially takes interdependence and global connection into account. The present paper gives the basic operations and properties of this kind of nonstandard logic using the model provided by the stochastic sets defined by joint probability (or credibility) distributions. The Cantor sets are obtained when the joint distributions are degenerate.

A proper motion study from Tautenburg Schmidt plates is presented for the globular cluster M 3 and its vicinity. The plates were scanned with the Automated Photographic Measuring (APM) system in Cambridge (UK). With a limiting magnitude of B = 21, proper motions of 2 to 3 mas/yr accuracy have been obtained for stars with B < 19. The proper motions were determined applying a stepwise regression method with 3rd order polynomials in the plate-to-plate solutions with about 2000 reference galaxies. We used the results for the determination of membership probabilities and looked for internal motions of M 3.

Analysis of a large micro-data set shows that state public-sector bargaining laws significantly influence state and local government union membership in several ways. Membership probability is lowest where a right-to-work law is present; it is greatest when there are mandatory agency shop provisions. Compulsory arbitration leads to a significantly greater probability of membership than does the right-to-strike. Simulations based on model estimates indicate that policy changes along the lines of proposed national public bargaining laws could lead to major changes in public-sector union density. Among individual and demographic characteristics, membership probability is significantly affected by full-time/part-time status and the statewide extent of private-sector unionism. Although non-whites and males are more likely to be union members, race and gender membership differentials are shown to be relatively small.

Using the relative proper motions of 1,067 stars in the region of the open cluster M67, we calculated the membership probability for each star by a maximum liklihood method. 375 stars were found to have probabilities greater than 0.65 and these were taken to be members. A discriminating analysis gave 412 members. Some comparison with Sanders' (1976) calculation is made.