Although there has been a notable increase in research on the effect of social relationships on turnover across different disciplines, including management, sociology, communication, applied ...psychology, corporate strategy, and economics over the past two decades, this stream of research has not been complied into a thorough and theoretically insightful review. In this article, we review and integrate the literature on social relationships and turnover by (a) defining social relationships broadly; (b) taking an interdisciplinary approach; (c) examining relational components embedded in turnover theories; (d) summarizing findings on the association between behavioral, structural, and psychological features of social relationships and turnover; (e) explaining how the findings can contribute to extant turnover theories; (f) discussing operationalizations of social relationships; (g) identifying limitations of prior research and theories; and (h) providing directions for future research. Our review charts what is known and unknown about the association between social relationships and turnover with the goal of laying out a path for moving forward.
ABSTRACT
Using new and published data, we construct a sample of 160 brightest cluster galaxies (BCGs) spanning the redshift interval 0.03 < z < 1.63. We use this sample, which covers 70 per cent of ...the history of the universe, to measure the growth in the stellar mass of BCGs after correcting for the correlation between the stellar mass of the BCG and the mass of the cluster in which it lives. We find that the stellar mass of BCGs increases by a factor of 1.8 ± 0.3 between z = 0.9 and z = 0.2. Compared to earlier works, our result is closer to the predictions of semi‐analytic models. However, BCGs at z = 0.9, relative to BCGs at z = 0.2, are still a factor of 1.5 more massive than the predictions of these models. Star formation rates in BCGs at z ∼ 1 are generally too low to result in significant amounts of mass. Instead, it is likely that most of the mass build up occurs through mainly dry mergers in which perhaps half of the mass is lost to the intra‐cluster medium of the cluster.
Employee turnover rates are among the highest for entry-level employees in the hospitality industry. Research focused on identifying the antecedents of turnover in this employment context has been ...limited, however. To address this gap in the literature, the present study examined the impact of coworker support on turnover with a sample of 188 servers from a national restaurant chain. Specifically, this study assessed the impact of coworker instrumental support and coworker emotional support on turnover. The results demonstrated that coworker emotional support was negatively related to turnover. However, coworker instrumental support was positively related to turnover, counter to the hypothesized relationship. This counterintuitive finding leads us to consider the role of coworker support on turnover in a new light.
We present Advanced Camera for Surveys, NICMOS, and Keck adaptive-optics-assisted photometry of 20 Type Ia supernovae (SNe Ia) from the Hubble Space Telescope (HST) Cluster Supernova Survey. The SNe ...Ia were discovered over the redshift interval 0.623 < z < 1.415. Of these SNe Ia, 14 pass our strict selection cuts and are used in combination with the world's sample of SNe Ia to derive the best current constraints on dark energy. Of our new SNe Ia, 10 are beyond redshift z = 1, thereby nearly doubling the statistical weight of HST-discovered SNe Ia beyond this redshift. Our detailed analysis corrects for the recently identified correlation between SN Ia luminosity and host galaxy mass and corrects the NICMOS zero point at the count rates appropriate for very distant SNe Ia. Adding these SNe improves the best combined constraint on dark-energy density, rho sub(DE)(z), at redshifts 1.0 < z < 1.6 by 18% (including systematic errors). For a flat LAMBDACDM universe, we find ohm sub(Lambda) = 0.729 + or - 0.014 (68% confidence level (CL) including systematic errors). For a flat wCDM model, we measure a constant dark-energy equation-of-state parameter w = -1.013 super(+0.068) sub(-0.073) (68% CL). Curvature is constrained to ~0.7% in the owCDM model and to 2% in a model in which dark energy is allowed to vary with parameters w sub(0) and w sub(a). Further tightening the constraints on the time evolution of dark energy will require several improvements, including high-quality multi-passband photometry of a sample of several dozen z > 1 SNe Ia. We describe how such a sample could be efficiently obtained by targeting cluster fields with WFC3 on board HST. The updated supernova Union2.1 compilation of 580 SNe is available at http://supernova.lbl.gov/Union.
Recent independent results from numerical simulations and observations have shown that brightest cluster galaxies (BCGs) have increased their stellar mass by a factor of almost 2 between z ∼ 0.9 and ...z ∼ 0.2. The numerical simulations further suggest that more than half this mass is accreted through major mergers. Using a sample of 18 distant galaxy clusters with over 600 spectroscopically confirmed cluster members between them, we search for observational evidence that major mergers do play a significant role. We find a major merger rate of 0.38 ± 0.14 mergers per Gyr at z ∼ 1. While the uncertainties, which stem from the small size of our sample, are relatively large, our rate is consistent with the results that are derived from numerical simulations. If we assume that this rate continues to the present day and that half of the mass of the companion is accreted on to the BCG during these mergers, then we find that this rate can explain the growth in the stellar mass of the BCGs that is observed and predicted by simulations. Major mergers therefore appear to be playing an important role, perhaps even the dominant one, in the build up of stellar mass in these extraordinary galaxies.
Abstract
We present an optical study of the strong-lensing galaxy cluster MS 0440.5+0204 at
z
= 0.19593, based on CFHT/MegaCam
g
′,
r
′ photometry and GMOS/Gemini and CFHT/MOS/SIS spectroscopy in a ...broader area than previous works. We have determined new spectroscopic redshifts for the most prominent gravitational arcs surrounding the central galaxy in the cluster. The new redshifts and the information provided by the photometric catalog allow us to perform a detailed weak- and strong-lensing mass reconstruction of the cluster. The large number of member galaxies and the area covered by our observations allow us to estimate more accurately the velocity dispersion and mass of the cluster and to examine in detail the nature of the cluster and surrounding structures. The dynamical mass is in good agreement with the mass inferred from the lensing analysis and X-ray estimates. About 68% of the galaxies are located in the inner ≲0.86
h
70
−
1
Mpc region of the cluster. The galaxy redshift distribution in the inner region of the cluster shows a complex structure with at least three substructures along the line of sight. Other substructures are also identified in the galaxy density map and in the weak-lensing mass map. The member galaxies in the northeast overdensity are distributed in a filament between the clusters MS 0440.5+0204 and ZwCL 0441.1+0211, suggesting that these two structures might be connected. MS 0440.5+0204 appears to be dynamically active, with a cluster core that is likely experiencing a merging process, and with other nearby groups at projected distances of ≲1
h
70
−
1
Mpc that could be being accreted by the cluster.
We study the surface brightness profiles of a sample of brightest cluster galaxies (BCGs) with 0.3 < z < 0.9. The BCGs are selected from the first Red-sequence Cluster Survey and an X-ray cluster ...survey. Although the single Sersic model fits the profiles well, we argue that the systematics in the sky background measurement and the coupling between the model parameters make the comparison of the best-fit model parameters ambiguous. For the very massive ETGs and BCGs, the slope of the Kormendy relation starts to trace the slope of the surface brightness profiles and becomes insensitive to subtle profile evolution. These results are generally consistent with dry mergers being the major driver of the mass growth for BCGs and massive ETGs. We also find strong correlations between the richness of clusters and the properties of BCGs; the more massive the clusters are, the more massive the BCGs (M* sub(bcg) is proportional to M super(0.6) sub(clusters )) and the shallower their surface brightness profiles.
Context. The connection of cluster mergers with the presence of extended, diffuse radio sources in galaxy clusters is still debated. An interesting case is the rich, merging cluster Abell 520, ...containing a radio halo. A recent gravitational analysis has shown in this cluster the presence of a massive dark core suggested to be a possible problem for the current cold dark matter paradigm. Aims. We aim to obtain new insights into the internal dynamics of Abell 520 analyzing velocities and positions of member galaxies. Methods. Our analysis is based on redshift data for 293 galaxies in the cluster field obtained combining new redshift data for 8 galaxies acquired at the TNG with data obtained by CNOC team and other few data from the literature. We also use new photometric data obtained at the INT telescope. We combine galaxy velocities and positions to select 167 cluster members around z sim0.201. We analyze the cluster structure using the weighted gap analysis, the KMM method, the Dressler-Shectman statistics and the analysis of the velocity dispersion profiles. We compare our results with those from X-ray, radio and gravitational lensing analyses. Results. We compute a global line-of-sight (LOS) velocity dispersion of galaxies, sigma_=1066_ km s super(-1). We detect the presence of a high velocity group (HVG) with a rest-frame relative LOS velocity of { v_{rf}}\sim 2000 km s super(-1) with respect to the main system (MS). Using two alternative cluster models we estimate a mass range M(\mbox{<}1; h_ 6\mathrm{Mpc}) =(4.0-9.6) similar to \times 10 logical or ; h_ similar to M_. We also find that the MS shows evidence of subclumps along two preferred directions. The main, complex structure {\cal NE}1+{\cal NE}2 (with a velocity comparable to that of the MS) and the {\cal SW} structure (at { v_{rf}}\sim +1100 km s super(-1)) define the NE-SW direction, the same of the merger suggested by X-ray and radio data. The {\cal E} and {\cal W} structures (at { v_{rf}}\sim-1150 and {v_{rf}}\sim-300 km s super(-1)) define the E-W direction. Moreover, we find no dynamical trace of an important structure around the lensing dark core. Rather, the HVG and a minor MS group, having different velocities, are roughly centered in the same position of the lensing dark core, i.e. are somewhat aligned with the LOS. Conclusions. We find that Abell 520 is definitely a very complex system. Our results suggest that we are looking at a cluster forming at the crossing of three filaments of the large scale structure. The filament aligned with the LOS and projected onto the center of the forming cluster might explain the apparent massive dark core shown by gravitational lensing analysis.
Research investigating the validity of personality measures has established these measures as useful selection tools. However, personality measures are vulnerable to response distortion leading to ...employer concerns about the influence of applicant faking, with specific concerns about the influence of social desirability. A traditional method used to circumvent this is the application of a correction based on a social desirability scale score. This study sought to evaluate whether such corrections are effective tools for removing the influence of intentional distortion. A within-subjects design facilitated comparisons between honest, faked, and corrected scores. The goal was to evaluate whether a social desirability correction allows one to approximate an individual's honest score. The results suggest that a social desirability correction is ineffective and fails to produce a corrected score that approximates an honest score. Results are interpreted with respect to applicant comparison and construct validity.
Cognitively loaded tests of knowledge, skill, and ability often contribute to decisions regarding education, jobs, licensure, or certification. Users of such tests often face difficult choices when ...trying to optimize both the performance and ethnic diversity of chosen individuals. The authors describe the nature of this quandary, review research on different strategies to address it, and recommend using selection materials that assess the full range of relevant attributes using a format that minimizes verbal content as much as is consistent with the outcome one is trying to achieve. They also recommend the use of test preparation, face-valid assessments, and the consideration of relevant job or life experiences. Regardless of the strategy adopted, it is unreasonable to expect that one can maximize both the performance and ethnic diversity of selected individuals.
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