Tukey-Type Distributions in the Context of Financial Data

Abstract

In one-parameter (θ) families, we were not aware of explicit hypothesis testing scenarios where maximal invariant statistics failed to distinguish the models. We start with a concrete example (Sec. 2.2) to highlight such a hypothesis testing problem involving markedly different models. In this problem, because of the absence of a nontrivial uniformly most powerful invariant (UMPI) test, we briefly suggest two approaches to test the hypothesis. The first resolution (Sec. 3.1) is frequentist in nature. It utilizes a weight function on the parameter space and compares “average” distributions obtained under the null and alternative models in the sense of Wald (1947 Wald , A. ( 1947 ). Sequential Analysis . New York : Wiley . [Google Scholar] 1950 Wald , A. ( 1950 ). Statistical Decision Functions . New York : Wiley . [Google Scholar]). In contrast, a fully Bayesian resolution (Sec. 3.2) is also included. The note ends with a series of other interesting examples involving one-parameter families where maximal invariant statistics fail to distinguish the hypothesized models. The examples include easy-to-construct families of probability models involving only a single location or scale parameter θ.     

Home gardening practice in Pune (India), the role of communities,urban environment and the contribution to urban sustainability

Urban Ecosystems - Urban agriculture (UA) is regarded as an emerging tool and strategy for sustainable urban development as it addresses a wide array of environmental, economic and social...     

Die Entwicklung der Fehler- und Feedbackkultur durch Team-Coaching

The development of an error culture and feedback culture by team coachingTeams and departments can be relieved of a tremendous burden and collaborate far more efficiently by mutually reflecting on making mistakes, giving and receiving feedback, calling meetings, trying things out in real life situations and, by doing so, establishing new forms of a culture that embraces failure and feedback. This approach works in areas such as team coaching. The purpose of this paper is to present a practical method for developing a team-based culture of learning from failure and feedback. The paper is designed to encourage professional trainers not to leave company employees and management on their own with the issue of establishing such a culture but to make the introduced tools a part of staff training, management and other company development programs as well as team workshops or to develop one’s own formats for introducing a culture of learning from failure and feedback.     

Kurtosis modelling by means of the J-transformation

Summary: The H–family of distributions or H–distributions, introduced by Tukey (1960; 1977), are generated by a single transformation of the standard normal distribution and allow for leptokurtosis represented by the parameter h. Alternatively, Haynes et al. (1997) generated leptokurtic distributions by applying the K–transformation to the normal distribution. In this study we propose a third transformation, the so–called J–transformation, and derive some properties of this transformation. Moreover, so-called elongation generating functions (EGFs) are introduced. By means of EGFs we are able to visualize the strength of tail elongation and to construct new transformations. Finally, we compare the three transformations towards their goodness–of–fit in the context of financial return data.     

Path-related empirical research on M&A-outcome: review and research agenda

This article attempts to reflect the current state and progress of contemporary research on financial and non-financial M&A outcome. Based on a review of 183 empirical M&A studies an integrative framework is developed, in which impact factors are classified into four major dimensions to explore the impact on M&A outcome: antecedents, transaction content characteristics, transaction process characteristics, and the transaction itself. The review reveals that M&A research is dominated by studies focusing on state variables at the expense of path-related variables. The review also shows that, to date, neither state-related research nor path-related research on financial and non-financial M&A outcome categories have reached maturity. Although there is still room for clarifying the impact of various state-related variables, the most valuable new insights are expected to emerge from researching path-related variables. Building on these insights, an extensive future research agenda is presented, which focuses on path-related research questions and methodological issues.     

Coaching als Befähigung

Coaching as an instrument of staff development is becoming increasingly popular. The different coaching concepts comprehend praxeological and methodological orientations, and their metatheoretical base often remains largely unreflected. This paper situates coaching as a distinct profession with a stand-alone approach within the sciences. In the sense that coaching processes transcend conflicts and presented topics on underlying needs attributed to significant connection points to the theories Johan Galtung and the “capability approach” resulting in the tradition of Amartya Sen and Martha Nussbaum. This is preceded by a meta-theoretical localization of the process of a praxeology of coaching.     

Drivers of biodiversity patterns in parks of a growing South American megacity

How urban habitats contribute to biodiversity conservation is a key challenge in a rapidly urbanising world. Urban parks can provide important habitats for native species, but previous studies are geographically biased; fast growing megacities, in particular in South America, are clearly understudied. To assess habitat functions and underlying drivers in parks of Santiago de Chile, we analysed the assemblages of wild growing plant species in two ubiquitous park habitat types (grasslands, wooded areas) in 15 parks (150 plots) along an urban-rural gradient. We first used linear contrasts to compare species richness, beta diversity and the proportion of introduced species. We then tested for the explanatory value of environmental variables operating at different spatial scales (plot, park, urban matrix). Unlike in most previous studies, biodiversity patterns were not related to the position of the parks on the urban-rural gradient. Introduced species, mostly from Europe, generally dominated both habitat types (>90 %). Socio-economic (population growth or density), but not spatial, variables were retained in most models. Maintenance intensity was most influential in predicting species assemblages, complemented by park age in wooded areas. A high proportion of European grassland species indicates a trend of homogenisation in park grassland at a cross-continental scale. We conclude that habitat functions of urban parks for native species that have been mainly demonstrated for Europe cannot be generalised to South American megacities. This highlights the need for innovative and locally appropriate conservation approaches (e.g., re-introduction of native species) to foster biodiversity functions in urban parks of South American megacities.     

Orientierungsprozesse im Vertrauensdilemma. Beziehungskonstruktionen in Beratungen zur privaten Altersvorsorge

Financial advice given by consultants is crucial for retirement saving decisions. We argue that those willing to save are facing a dilemma since there is a widespread mistrust towards the financial industry while financial advice is indispensable for coping with complexity in the decision process. Exploring the case of the state-subsidized Riester-pension in Germany, we show that savers construct personal relationships with the advisor to deal with this complex dilemma in terms of theories on trust. Using a mixed-method design embracing both quantitative techniques—cross-sectional as well as longitudinal (fixed-effects) approaches—and qualitative evidence, we shed new light on old age saving decisions. In detail, the exploitation of longitudinal surveys (of GSOEP and the German SAVE Panel 2004–2010) and of 18 problem-centred interviews provides the following findings: (1) Retirement saving decisions often rely on pre-existing relationships to financial advisors. (2) The less alternative resources available, the more savers rely on these relationships. (3) Financial advisors use their existing relationships to sell pensions. (4) The qualitative material unveils different patterns concerning the decision-making process which are trusteeship, strategic alliance, and acceptable ad-hoc collaboration. Altogether, the widespread idea of private retirement saving resulting from an atomistic and rational planning of the future is an illusion.