Impulse Balance and Multiple‐Period Feedback in the Newsvendor Game

Human subjects in the newsvendor game place suboptimal orders: orders are typically between the expected profit‐maximizing quantity and mean demand (“pull‐to‐center bias”). In previous work, we have shown that impulse balance equilibrium (IBE), which is based on a simple ex post rationality principle along with an equilibrium condition, can predict ordering decisions in the laboratory. In this study, we extend IBE to standing orders and multiple‐period feedback and show that it predicts—in line with previous findings—that constraining newsvendors to make a standing order for a sequence of periods moves the average of submitted orders toward the optimum.     

Aller Anfang ist schwer — Problem-und Zieldefinition in der Organisationsberatung

The article examines the initial phase of (management) consulting projects from a sociological perspective. The main focus lies on the processes of defining the initial problems that lead to the consulting project and the goals of the project. The article describes the clarification process carried out jointly by consultants and clients in the first phase of a project. After stressing the importance of these activities for project success, the factors that might disturb these processes are then analyzed and discussed, primarily following system-theoretical and micro-political considerations.     

中红外光谱检测土壤中碳酸盐——什么最重要

碳酸盐检测是土壤科学中的常规检测。在本研究中,用中红外光谱方法对采自奥地利130多个不同的森林区域的大量土壤样品进行评价。评价了有机层中的20条谱带和矿物土壤中15条谱带区域,并且通过模型计算检测了被调查土壤样品中的碳酸盐。对于有机层的所有样品,相关系数都很低(R2=0.68),可以通过对F(中度分解的有机物)和H(高度腐烂的有机物质)的混合样品进行组分离来增加相关系数。FH层土壤、森林类型土壤、矿质土壤母质的相关系数达到R2=0.92。对于所有0到5和5至10cm的矿质土壤层,相关系数从一开始就很高(R2=0.97),当隔离一组石灰岩作为母质的10个样品时,相关系数可以增加到R2=0.99。最后,本研究着重介绍了土壤样品的化学多样性对于中红外光谱检测土壤中碳酸盐的影响潜力。     

Impaired Metacognitive Capacities in Individuals with Problem Gambling

Impaired insight into behavior may be one of the clinical characteristics of pathological gambling. In the present study, we tested whether the capacity to evaluate accurately the quality of one’s own decisions during a non-gambling task was impaired in problem gamblers. Twenty-five problem gamblers and 25 matched healthy participants performed an artificial grammar-learning paradigm, in which the quality of choice remains uncertain throughout the task. After each trial of this task, participants had to indicate how confident they were in the grammaticality judgements using a scale ranging from 1 (low confidence) to 7 (high confidence). Results showed that (i), problem gamblers’ performance on the grammaticality test was lower than controls’; (ii) there was a significant correlation between grammaticality judgments and confidence for control participants, which indicates metacognitive insight and the presence of conscious knowledge; (iii) this correlation was not significant in problem gamblers, which suggests a disconnection between performance and confidence in this group. These findings suggest that problem gamblers are impaired in their metacognitive abilities on a non-gambling task, which suggests that compulsive gambling is associated with poor insight as a general factor. Clinical interventions tailored to improve metacognition in gambling could be a fruitful avenue of research in order to prevent pathological gambling.     

Transactional Sex: Supply and Demand Among European Men Who have Sex with Men (MSM) in the Context of Local Laws

Objectives: Transactional sex (TS) is generally defined as the trading of sex for material goods. Cast within the broader context of prostitution laws, we examined variations in the sociodemographic profile of men who have sex with men engaging in TS by payment direction (buying/selling). Methods: The data were collected as part of the 38-country European Men who have sex with men Internet Survey project, conducted in 2010. Results: About 12% of respondents reported engaging in TS in the past year. TS was associated with laws, age, education, employment, and residence. Conclusions: The striking sociodemographic differences in TS by payment direction suggest a power differential and a leading role of socioeconomic factors in TS.     

Checking a Semiparametric Additive Risk Model

McKeague and Sasieni [A partly parametric additive risk model. Biometrika 81 (1994) 501] propose a restriction of Aalen’s additive risk model by the additional hypothesis that some of the covariates have time-independent influence on the intensity of the observed counting process. We introduce goodness-of-fit tests for this semiparametric Aalen model. The asymptotic distribution properties of the test statistics are derived by means of martingale techniques. The tests can be adjusted to detect particular alternatives. As one of the most important alternatives we consider Cox’s proportional hazards model. We present simulation studies and an application to a real data set.     

The representation of street art on Flickr. Studying reception with visual content analysis

Street art is public art; it’s accessible; it’s of the people; it’s an urban voice; it’s on public view; it’s on-the-street. Nonetheless, the World Wide Web has been party responsible for street art becoming both recognised and popular. As a result, this study is investigating how street art is represented on the open photo-sharing platform, Flickr. It is a social network site offering a large portfolio of photographs showing a wide range of images, which have been categorised and classified using ‘tags’. By using a visual content analysis based on theoretically determined categories to examine the uploaded photographs, this investigation will shed light on what a selection of Flickr users recognise as street art and how they record and index it.