Kooperation unter Konkurrenten? Regionale Kulturmuster und soziale Praktiken betriebsübergreifender Personalwirtschaft

During the recent financial and economic crisis, trade unions and employers’ associations have increasingly concluded collective agreements on so-called “collegial temporary work” that enables flexible deployment of employees, especially for small and medium sized enterprises. Empirical results show large differences in the application of those collective agreements: While the possibilities of the agreements were sometimes actively used in some regions, companies in other regions avoided implementation – despite their potential to cope with important challenges of economic crises and skill shortages. The paper selects a structuration theory perspective to analyze the reasons for the differences in the practice of this human resource management strategy by comparing two German regions (Braunschweig and the Ruhr area). The differences in the practices can be traced back to regional cultural patterns, interests of key actors, and the degree of involvement during the implementation period.     

Protecting the Old in a Young Economy: Old Age Insurance in the West Bank and Gaza Strip

Taking the West Bank and Gaza Strip as a reference point, this paper looks at social protection in developing economies, which are beset by economic stagnation, widespread poverty and unemployment. If the main breadwinner dies, is unable to work or is an older person, these factors are prime causes of absolute poverty. This is hardly surprising, since private and public systems of social security are totally inadequate in this area in particular. Current thinking on social security suggests that what is needed is the rapid introduction of a comprehensive system of retirement provision, comprising a mandatory capital-funded insurance component, with defined contributions, administered on a decentralized basis; and a state-administered pay-as-you-go basic insurance component with lump-sum transfers to safeguard the poorest. A system of this kind works to prevent poverty in old age by redistributing funds from some individuals to others and ensuring an income for life, and it represents a compromise between a fair return on what people have contributed and a fair distribution over society as a whole. It is thus a major force for stability in society.     

Mother–infant Interaction Quality and Infants' Ability to Encode Actions as Goal‐directed

The current study investigated the relationship between mother–child interaction quality and infants' ability to interpret actions as goal‐directed at 7 months in a sample of 37 dyads. Interaction quality was assessed in a free play interaction using two distinct methods: one assessed the overall affective quality (emotional availability), and one focused on the mother's proclivity to treat her infant as an intentional agent (mind‐mindedness). Furthermore, infants' ability to interpret human actions as goal‐directed was assessed. Analyses revealed that only maternal emotional availability, and not maternal mind‐mindedness, was related to infants' goal‐encoding ability. This link remained stable even when controlling for child temperament, working memory, and maternal education. These findings provide first evidence that emotionally available caregiving promotes social‐cognitive development in preverbal infants.     

Estimating the Spot Covariation of Asset Prices—Statistical Theory and Empirical Evidence

ABSTRACT

We propose a new estimator for the spot covariance matrix of a multi-dimensional continuous semimartingale log asset price process, which is subject to noise and nonsynchronous observations. The estimator is constructed based on a local average of block-wise parametric spectral covariance estimates. The latter originate from a local method of moments (LMM), which recently has been introduced by Bibinger et al.. We prove consistency and a point-wise stable central limit theorem for the proposed spot covariance estimator in a very general setup with stochastic volatility, leverage effects, and general noise distributions. Moreover, we extend the LMM estimator to be robust against autocorrelated noise and propose a method to adaptively infer the autocorrelations from the data. Based on simulations we provide empirical guidance on the effective implementation of the estimator and apply it to high-frequency data of a cross-section of Nasdaq blue chip stocks. Employing the estimator to estimate spot covariances, correlations, and volatilities in normal but also unusual periods yields novel insights into intraday covariance and correlation dynamics. We show that intraday (co-)variations (i) follow underlying periodicity patterns, (ii) reveal substantial intraday variability associated with (co-)variation risk, and (iii) can increase strongly and nearly instantaneously if new information arrives. Supplementary materials for this article are available online.     

Using crushed waste bricks for urban greening with contrasting grassland mixtures: no negative effects of brick-augmented substrates varying in soil type,moisture and acid pre-treatment

Ecological restoration aims at supporting biodiversity and ecosystem services, and urban greening is a great opportunity to achieve this goal. This is facilitated by species-rich seed mixtures based on local provenances, which are designed for certain nutrient and moisture regimes based on functional plant traits. Such grassland mixtures might be cultivated on crushed waste bricks, which would be a new component of water-holding urban substrates. Thus, we studied the effects of brick quantity and quality, acid pre-treatment of bricks, soil type and moisture on biomass of designed seed mixtures. Three greenhouse experiments were conducted, with substrates consisting of different brick ratios (5% vs. 30%), brick types (clean production waste vs. demolition material), and brick treatments (acid vs. control) tested on three trait-based mixtures and a non-regional commercial standard mixture. The trait-based mixtures included information on specific leaf area, seed mass and grass-to-legume ratio. There were no negative effects of demolition bricks, soil texture and moisture on grassland biomass. Acid-treated clean porous bricks improved biomass production of the standard and intermediate mixtures, while the effect was minimal with demolition bricks. Designed seed mixtures had a biomass similar to the standard mixture under dry conditions but did not benefit from high moisture like the standard mixture. In conclusion, waste bricks are a useful additive for urban restoration substrates to save raw material, and specifically designed regional mixtures can replace commercial grassland types on these substrates.

     

Permutation tests — A revival?!

It is shown that permutation tests have optimum properties for interesting classes of continuous distributions as well as for discrete ones. General conditions sufficient for uniformly maximal power on subclasses are given. Moreover, a variety of examples is presented. Research supported by Deutsche Forschungsgemeinschaft (DFG) grant No. Schm 677/5-1     

Woodland fragments in urban landscapes are important bat areas: an example of the endangered Bechstein’s bat Myotis bechsteinii

Urban Ecosystems - Urban areas are increasing globally causing fragmentation and loss of habitats for many forest dwelling species. At the same time new habitats are created, which may be exploited...     

Die Mehrebenen-Analyse. Ihre praktische Anwendung und theoretische Annahmen

Multilevel analysis has become more common during the last ten years. A reason might be that this method allows us to analyse micro- and macro relationships in one step. Loosely, one can characterize it as a combination of variance analysis and regression analysis. Nevertheless, questions occur frequently concerning its practical application, the statistical requirements, the differences to OLS-Regression, and so on. Answering these questions, this paper has two particular aims. The first aim is to show the practical use and to give an idea of the possibilities of this method. The second aim is to discuss statistical requirements and frequently asked questions. For this purpose the application of a two level regression is illustrated by using data from ISSP and analysing the perception of vertical conflicts in an international view. This paper starts with a practical application. The random intercept model is discussed, where the intercepts vary among macro units and therefore regression lines run at different levels. Afterwards a random slope model is shown. Here, the regression coefficients also vary among countries. Among these practical applications other topics are discussed, e. g. model fit, minimum sample size, explained variance, estimation-methods, and standardisation of coefficients. Finally there is given a brief overview of this method and different software programs.     

Maximum Test versus Adaptive Tests for the Two-Sample Location Problem

For the non-parametric two-sample location problem, adaptive tests based on a selector statistic are compared with a maximum and a sum test, respectively. When the class of all continuous distributions is not restricted, the sum test is not a robust test, i.e. it does not have a relatively high power across the different possible distributions. However, according to our simulation results, the adaptive tests as well as the maximum test are robust. For a small sample size, the maximum test is preferable, whereas for a large sample size the comparison between the adaptive tests and the maximum test does not show a clear winner. Consequently, one may argue in favour of the maximum test since it is a useful test for all sample sizes. Furthermore, it does not need a selector and the specification of which test is to be performed for which values of the selector. When the family of possible distributions is restricted, the maximin efficiency robust test may be a further robust alternative. However, for the family of t distributions this test is not as powerful as the corresponding maximum test.     

Individuelle und kontextuelle Determinanten der Teilhabe an Sozialkapital

We ask for conditions influencing membership in social organizations as strongholds of social capital. Beside individual characteristics, contextual factors such as political, social, or economic settings are also taken into consideration to explain individual decisions to participate in social organizations. The influences of individual and contextual level factors are tested simultaneously in several multi-level analyses. The results show that membership in social associations on the one hand is affected by individual characteristics such as marked trust in others, high level of education, church attendance, strong ties with the neighbourhood, age and sex, and on the other hand by contextual factors such as a catholic social context and institutional settings. In particular, Swiss direct democracy offering larger possibilities of participation facilitates membership in social organizations.