Comparisons of approximate confidence intervals for the smallest extreme value distribution simple linear regression model under time censoring

Exact confidence interval estimation for accelerated life regression models with censored smallest extreme value (or Weibull) data is often impractical. This paper evaluates the accuracy of approximate confidence intervals based on the asymptotic normality of the maximum likelihood estimator, the asymptotic X²distribution of the likelihood ratio statistic, mean and variance correction to the likelihood ratio statistic, and the so-called Bartlett correction to the likelihood ratio statistic. The Monte Carlo evaluations under various degrees of time censoring show that uncorrected likelihood ratio intervals are very accurate in situations with heavy censoring. The benefits of mean and variance correction to the likelihood ratio statistic are only realized with light or no censoring. Bartlett correction tends to result in conservative intervals. Intervals based on the asymptotic normality of maximum likelihood estimators are anticonservative and should be used with much caution.     

A Model of the Macroeconomic Effects of Privatization on Employment in Transition and Developing Countries with an Application to China

It is generally agreed that privatization of state-owned enterprises improves economic efficiency, but it is also widely feared that it exacerbates unemployment especially in transition and developing economies. This paper proposes a theoretical model of the macroeconomic relationships between privatization, efficiency, output, and employment. The model explains how privatization affects employment in transition and developing economies through different, and often opposing, channels. As a result, job losses at firms being privatized may result in overall job gains or losses in the economy, depending on the macroeconomic conditions. We apply this model to China and find that the model provides an intuitively appealing explanation for the job gains and losses caused by privatization in China during its transition. The model further suggests policies to maximize the gains and minimize the costs of privatization.     

The survival of newly founded firms: a case-study into varying-coefficient models

Summary.  The success of a newly founded firm depends on various initial risk factors or start-up conditions such as the market that the business is aiming for, the experience and the age of the founder, the preparation before the launch, the financial frame and the legal form of the firm. These risk factors determine the chance of survival for the venture. However, the effects of these risk factors may change with time. Some effects may vanish whereas others remain constant. We analyse the survival of 1123 newly founded firms in the state of Bavaria, Germany. Our focus is on the investigation of time variation in the effects of risk factors. Time variation is tackled within the framework of varying-coefficient models, where time smoothly modifies the effects of risk factors. An important issue in our analysis is the separation of risk factors which have time-varying effects from those which have time constant effects. We make use of the Akaike criterion to separate these two types of risk factor.     

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Aus der Praxis: Erfolgsfaktoren der Post-Merger Integration

The article describes the internationalization process of a Facility Management company. Five key factors for success have been identified: new perspectives for employees, maintenance of independency + homogenization of structures, transparency, internationalization of management and formation of a common identity. The role of organization development in this process and future challenges for post-merger integration are depicted.     

Wirkprinzipien handlungsorientierter Beratungs- und Trainingsmethoden

The article suggests effect principles of action-oriented methods for organizational counselling and training. It is shown that action-oriented methods use “surplus reality” (a concept developed by J. L. Moreno) as a constitutive medium in which they duplicate organizational reality by means of scenic embodiment. The authors show how action-oriented methods derive their specific potential for the depiction and reflection of work-related problems in organizational counselling, training, supervision and coaching from this surplus reality.     

National Income,Political Freedom,and Investments in R&D and Education: A Comparative Analysis of the Second Digital Divide Among 15-Year-Old Students

Social Indicators Research - Digital technology has become an indispensable component in education around the world. Despite its growing importance, a gap in students’ digital skills and...     

Renaissance of a rural artifact in a city with a million people: biodiversity responses to an agro-forestry restoration in a large urban traditional fruit orchard

The rural landscapes surrounding large cities are rapidly becoming incorporated into the urban environment. The most conspicuous changes involve green spaces, such as former agro-forestry systems like fruit orchards. In this paper, we assess the influence on biodiversity of restoring a large urban traditional fruit orchard as reflected by six selected taxa: plants, lichens, butterflies, beetles, orthopteroids and birds. The study was performed in Prague, which is the capital city of the Czech Republic and has more than a million inhabitants. We studied the effect of orchard renewal in 45 patches (15 for birds and 30 for other taxa). The majority of taxa responded positively to the restoration. The restoration had a significant positive effect on the species richness of lichens, butterflies and beetles. All taxa showed significantly altered species compositions, and the number of red-listed species increased. Orchards have a high potential for multi-functional use. Orchards are productive agro-forestry systems and host numerous possible human activities. Therefore, orchard restoration also has a social aspect. Moreover, our research in this artificial ecosystem revealed that its restoration increased the biodiversity and conservation potential of the associated areas.

     

Approximations of Studentás t and chi-square percentage points

Three tables provide coefficients for polynomial approximations of Student's t and chi-square percentage points at 10 probability levels, with relative error less than .00005