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Human decision making in the newsvendor context has been analyzed intensively in laboratory experiments, where various decision biases have been identified. However, it is unclear whether the biases also exist in practice. We analyze the ordering decisions of a manufacturer who faces a multiproduct newsvendor problem with an aggregate service‐level constraint. We find that the manufacturer broadly exhibits the same biases as subjects in the laboratory and is prone to another bias that has not been identified before, that is, group aggregation. The bias can be attributed to the multi‐product problem of the manufacturer, and refers to the observation that the service levels are not optimized for individual products, but rather for product groups. Our data allow us to analyze the performance of a manufacturer in detail and we find that target service levels are achieved effectively, but not efficiently. We provide rationales for the manufacturer's ordering behavior, discuss managerial implications, and quantify the financial benefits of debiasing ordering decisions. [ABSTRACT FROM AUTHOR]

We examine inventory decisions in a multiperiod newsvendor model. In particular, we analyze the impact of budget cycles in a behavioral setting. We derive optimal rational decisions and characterize the behavioral decision‐making process using a short‐sightedness factor. We test the aforementioned effect in a laboratory environment. We find that subjects reduce order‐up‐to levels significantly at the end of the current budget cycle, which results in a cyclic pattern during the budget cycle. This indicates that the subjects are short‐sighted with respect to future budget cycles. To control for inventory that is carried over from one period to the next, we introduce a starting‐inventory factor and find that order‐up‐to levels increase in the starting inventory. [ABSTRACT FROM AUTHOR]

Aim: This study analysed how nursing workloads in a neonatal intensive care unit (NICU) depended on the type of respiratory support provided, and how this relationship varied by the infant's postnatal age and weight.Methods: We used a prospective study design in a NICU in a tertiary perinatal centre in Germany. This entailed collecting data on nursing activities by observing 41 nurses for 155 hours between June 2015 and November 2015 and measuring the average nursing capacity required for direct care. Regression analysis was used to test for differences in nursing workloads between respiratory support types.Results: Mechanically ventilated infants each required an average of 60% of the time one nurse had available to spend on direct care during the periods observed. In contrast, those receiving noninvasive ventilation only required 34% and special care infants required 13%. After the first 72 hours of life, mechanically ventilated infants required an average nursing capacity of 40%, while infants receiving noninvasive ventilation required 32% and special care infants required 25%.Conclusion: Invasive support was associated with higher workloads than noninvasive support. The differences were partially moderated by individual factors, such as the infant's age. The findings should be replicated within a multicentre design. [ABSTRACT FROM AUTHOR]

Important but rare and subtle processes driving galaxy morphology and star formation may be missed by traditional spiral, elliptical, irregular or Sérsic bulge/disc classifications. To overcome this limitation, we use a principal component analysis (PCA) of non-parametric morphological indicators (concentration, asymmetry, Gini coefficient, M20, multimode, intensity and deviation) measured at rest-frame B band (corresponding to HST/WFC3 F125Wat 1.4 1010M⊙) galaxy morphologies. PCA quantifies the correlations between these morphological indicators and determines the relative importance of each. The first three principal components (PCs) capture ~75 per cent of the variance inherent to our sample. We interpret the first PC as bulge strength, the second PC as dominated by concentration and the third PC as dominated by asymmetry. Both PC1 and PC2 correlate with the visual appearance of a central bulge and predict galaxy quiescence. PC1 is a better predictor of quenching than stellar mass, as good as other structural indicators (Sérsic-n or compactness). We divide the PCA results into groups using an agglomerative hierarchical clustering method. Unlike Sérsic, this classification scheme separates compact galaxies from larger, smooth protoelliptical systems, and star-forming disc-dominated clumpy galaxies from star-forming bulge-dominated asymmetric galaxies. Distinguishing between these galaxy structural types in a quantitative manner is an important step towards understanding the connections between morphology, galaxy assembly and star formation. [ABSTRACT FROM AUTHOR]

We study the stellar mass Tully-Fisher relation (TFR; stellar mass versus rotation velocity) for a morphologically blind selection of emission line galaxies in the field at redshifts 0.1 < z < 0.375. Kinematics (σg, Vrot) are measured from emission lines in Keck/DEIMOS spectra and quantitative morphology is measured from V- and I-band Hubble images. We find a transition stellar mass in the TFR, log M*/M⊙ = 9.5. Above this mass, nearly all galaxies are rotation dominated, on average more morphologically disc-like according to quantitative morphology, and lie on a relatively tight TFR. Below this mass, the TFR has significant scatter to low rotation velocity and galaxies can either be rotation-dominated discs on the TFR or asymmetric or compact galaxies which scatter off. We refer to this transition mass as the 'mass of disc formation', Mdf because above it all star-forming galaxies form discs (except for a small number of major mergers and highly star-forming systems), whereas below it a galaxy may or may not form a disc. [ABSTRACT FROM AUTHOR]

From mock Hubble Space Telescope images, we quantify non-parametric statistics of galaxy morphology, thereby predicting the emergence of relationships among stellar mass, star formation, and observed rest-frame optical structure at 1 < z < 3. We measure automated diagnostics of galaxy morphology in cosmological simulations of the formation of 22 central galaxies with 9.3 < log10M*/M⊙ < 10.7. These high-spatial-resolution zoom-in calculations enable accurate modelling of the rest-frame UV and optical morphology. Even with small numbers of galaxies, we find that structural evolution is neither universal nor monotonic: galaxy interactions can trigger either bulge or disc formation, and optically bulge-dominated galaxies at this mass may not remain so forever. Simulated galaxies with M* > 1010M⊙ contain relatively more disc-dominated light profiles than those with lower mass, reflecting significant disc brightening in some haloes at 1 < z < 2. By this epoch, simulated galaxies with specific star formation rates below 10-9.7 yr-1 are more likely than normal star-formers to have a broader mix of structural types, especially at M* > 1010M⊙. We analyse a cosmological major merger at z ~ 1.5 and find that the newly proposed Multimode-Intensity-Deviation (MID) morphology diagnostics trace later merger stages while Gini-M20 trace earlier ones. MID is sensitive also to clumpy star-forming discs. The observability time of typical MID-enhanced events in our simulation sample is <100 Myr. A larger sample of cosmological assembly histories may be required to calibrate such diagnostics in the face of their sensitivity to viewing angle, segmentation algorithm, and various phenomena such as clumpy star formation and minor mergers. [ABSTRACT FROM AUTHOR]

At local, galaxy properties are well known to be clearly different in different environments. However, it is still an open question how this environment-dependent trend has been shaped. We present the results of our investigation about the evolution of star-formation properties of galaxies over a wide redshift range, from z ~ 2 to z ~ 0.5, focusing its dependence on their stellar mass and environment (Lee et al. 2015). In the UKIDSS/UDS region, covering ~2800 square arcmin, we estimated photometric redshifts and stellar population properties, such as stellar masses and star-formation rates, using the deep optical and near-infrared data available in this field. Then, we identified galaxy cluster candidates within the given redshift range. Through the analysis and comparison of star-formation (SF) properties of galaxies in clusters and in field, we found interesting results regarding the evolution of SF properties of galaxies: (1) regardless of redshifts, stellar mass is a key parameter controlling quenching of star formation in galaxies; (2) At z < 1, environmental effects become important at quenching star formation regardless of stellar mass of galaxies; and (3) However, the result of the environmental quenching is prominent only for low mass galaxies (M* < 1010 M⊙) since the star formation in most of high mass galaxies are already quenched at z > 1. [ABSTRACT FROM PUBLISHER]