Ausländische Investoren und einheimische Zulieferer in Transformationsökonomien: Was befördert positive externe Effekte?

The empirical study analyses the potential for positive external effects from foreign investors in favor of domestic firms using the IWH-FDI micro database and taking into account firm-specific characteristics of foreign investors in selected Central and East European countries as well as in Eastern Germany. The analysis shows that only half of the foreign investors believe that they are important for technological activities in domestic supplier firms. Thereby, the potential for external positive effects is higher in Central and Eastern Europe than in Eastern Germany. A reason for this might be that supplier firms in Eastern Germany already operate on a clearly higher technological level than their counterparts in Central and Eastern Europe. Taking into account the share of domestic supplies of foreign investors, it shows that the potential for positive external effects increases only to a certain point from which on the spillover potential stagnates or even declines. Furthermore, there is clear evidence for the following characteristics of foreign investors to increase the potential for positive external effects: innovativeness of the foreign investor, internal and external technological cooperation of foreign investors, independence from the headquarters in research and development issues and market entry through acquisition (instead of greenfield investment). The share of foreign participation as well as the duration of presence in the host economy does not show any statistically significant effect on the potential for external effects. Policy makers should therefore not only aim at the settlement of employment intensive foreign investors, but also and particularly support investors that are characterized by technological activity and regional integration.

Nonparametric Two-Sample Test for Networks Using Joint Graphon Estimation

This paper focuses on the comparison of networks on the basis of statistical inference. For that purpose, we rely on smooth graphon models as a nonparametric modeling strategy that is able to capture complex structural patterns. The graphon itself can be viewed more broadly as density or intensity function on networks, making the model a natural choice for comparison purposes. Extending graphon estimation towards modeling multiple networks simultaneously consequently provides substantial information about the (dis-)similarity between networks. Fitting such a joint model - which can be accomplished by applying an EM-type algorithm - provides a joint graphon estimate plus a corresponding prediction of the node positions for each network. In particular, it entails a generalized network alignment, where nearby nodes play similar structural roles in their respective domains. Given that, we construct a chi-squared test on equivalence of network structures. Simulation studies and real-world examples support the applicability of our network comparison strategy.Comment: 25 pages, 6 figure

Testing measurement Invariance in a CFA framework – State of the art

In recent years, several studies have stressed out the importance to guarantee the comparability of theoretical constructs (i.e. measurement invariance) in the compared units (e.g., groups or time points) in order to conduct comparative analyses (e.g. Harkness, Van de Vijver, & Mohler, 2003; Meredith, 1993; Vandenberg, & Lance, 2000). If one does not test for measurement invariance (MI) or ignores lack of invariance, differences between groups in the latent constructs cannot be unambiguously attributed to ‘real’ differences or to differences in the measurement attributes. One approach to test for MI is in a confirmatory factor analysis (CFA) framework. In this framework, MI is usually tested with a series of model comparisons that define more and more stringent equality constraints. The presentation will be about new developments in the MI-CFA framework. Among other things, the presentation tries to answer the following questions: • Which scale setting method to use (marker variable, fixed factor or effect coding method) when testing for MI? • Should a top-down- or bottom-up-approach be used? • How to test MI with a large number of groups (>30)? • What are the possibilities to evaluate whether MI exists (e.g., statistical significance of the ∆² after Bonferroni adjustment, changes in approximate fit statistics, magnitude of difference between the parameter estimates)? • How to determine confidence intervals for fit indices? • Can MI be graphically analyzed? • How can be dealt with non-invariance? These questions will be tried to answered by an application to a real world dataset (N ~ 40.000), with a one-factor/five indicator model of a well-being scale tested in 35 groups

Testing measurement invariance in a confirmatory factor analysis framework – State of the art

In recent years, several studies have stressed out the importance to guarantee the comparability of theoretical constructs (i.e. measurement invariance) in the compared units (e.g., groups or time points) in order to conduct comparative analyses (e.g. Harkness, Van de Vijver, & Mohler, 2003; Meredith, 1993; Vandenberg, & Lance, 2000). If one does not test for measurement invariance (MI) or ignores lack of invariance, differences between groups in the latent constructs cannot be unambiguously attributed to ‘real’ differences or to differences in the measurement attributes. One approach to test for MI is in a confirmatory factor analysis (CFA) framework. The presentation will be about new developments in the MI-CFA framework. Among other things, the presentation tries to answer the following questions: • Which scale setting method to use (marker variable, fixed factor or effect coding method) when testing for MI? • Should a top-down- or bottom-up-approach be used? • How to test MI with a large number of groups (>30)? • What are the possibilities to evaluate whether MI exists (e.g., statistical significance of the change in chi-square after Bonferroni adjustment, changes in approximate fit statistics, magnitude of difference between the parameter estimates)? • How to determine confidence intervals for fit indices? • Can MI be graphically analyzed? • How can be dealt with non-invariance? These questions will be tried to answered by an application to a real world dataset (N ~ 40.000), with a one-factor/five indicator model of a well-being scale tested in 35 groups

Force spectroscopy and single molecule detection with optical tweezers

Sischka A. Kraftspektroskopie und Einzelmoleküldetektion mit der Optischen Pinzette. Bielefeld (Germany): Bielefeld University; 2005.A compact, single beam optical tweezers system for force measurements and manipulation of individual double-stranded DNA (dsDNA) molecules was integrated into a commercial inverted optical microscope. A maximal force of 350 pN combined with a force sensitivity of less than 0.5 pN allows measurements of elastic properties of single molecules which complements and overlaps the force regime accessible with atomic force microscopy (AFM). The manipulation and measurement performance of this system was tested with individual Lambda DNA molecules and renders new aspects of dynamic forces phenomena with higher precision in contrast to AFM studies. An integrated liquid handling system with a fluid cell allows investigation of the force response of individual DNA molecules in the presence of DNA binding agents. Mechanical properties of double-stranded DNA (dsDNA) in the presence of different binding ligands were analyzed in optical tweezers experiments with sub-piconewton force resolution. Different binding modes could unambiguously be distinguished by analyzing the mechanic response of a dsDNA molecule to an applied external force. We compared the effects of the minor groove binder distamycin-A, a major groove binding alpha-helical peptide, the intercalator ethidium bromide, YO-1 and daunomycin as well as the bisintercalator YOYO-1 on Lambda DNA. Binding of molecules to the minor and major groove to dsDNA induces distinct changes in the molecular elasticity compared to the free dsDNA detectable as a shift of the B-S transition to higher forces. Intercalating molecules affect the molecular mechanics by a complete disappearance of the B-S transition and an associated increase in molecular contour length. Significant force hysteresis effects occurring during stretching/relaxation cycles with velocities in the range between 100 nm/s and 12,000 nm/s were found for daunomycin YOYO-1. These time dependent mechanical properties directly reflect the kinetics of the binding and unbinding. Force dependent time constants of 0.29 - 1.34 s and 0.15 - 0.60 s were determined for YOYO-DNA complexes and daunomycin-DNA complexes, respectively. Also we used the optical tweezer setup as an optiomechanical force transducer to analyze the rupture forces between mouse anti-chicken immunoglobulin class M (Anti-IgM) coupled to the surface of a trapped bead and membrane-bound B-cell receptors (immunoglobulin class M) on living chicken DT40 B-cells. The experiment exhibits specific single and multiple bond interactions and dissociations when an external force was applied. At a loading rate of 45 pN/s a single bond rupture force of 12.5 pN and integer multiples of this value during multiple bond rupturing could be identified. These experiments will allow interesting and important in-vitro testing of living cells in the future.Sowohl die Untersuchung der Elastizität kettenförmiger Polymere, die Charakterisierung der Bindung kleiner Moleküle, wie beispielsweise Peptide und Proteine, an eine DNA als auch Kraftmessungen zwischen Liganden und Rezeptoren in oder auf den verschiedensten biologischen Systemen, unter anderem mit der Zielsetzung, Kinetik, Gleichgewichtszustände, strukturelle Charakteristika oder Details der Energielandschaft der Bindungen zu beschreiben - sie alle verlangen nach äußerst sensitiven Kraftmessmethoden. Die beiden prominentesten Techniken sind hierbei die AFM-Kraftspektroskopie und die Optische Pinzette, die parallel zu ihrer überragenden Kraftauflösung auch weit in den Bereich der höheren Kräfte des AFMs vordringen kann. Das Prinzip der Optischen Pinzette basiert auf einem stark fokussierten Laserstrahl, der es ermöglicht, eine dreidimensionale Optische Falle - oder auch Photonisches Potential - zu generieren. Darin können Objekte der Größe einzelner Atome bis hin zu mehreren Dutzend Mikrometern gefangen werden. Das gezielte Fangen und Bewegen von Objekten mit Hilfe der Optischen Falle stellt nur eine Facette der Möglichkeiten dieses Systems dar. Weitaus verfeinerter sind die Mittel, das gefangene Objekt als einen Sensor für äußere Kräfte in dessen unmittelbarer Umgebung zu benutzen. Hierbei können die Auslenkungen des Objektes - welches bei den meisten biophysikalisch relevanten Untersuchungen ein transparentes Kügelchen ist - in eine Kraft übersetzt werden. Im Gegensatz zum AFM, bei dem für Kraftmessungen biochemisch präparierte Oberflächen benötigt werden, kann sich bei der Optischen Pinzette beispielsweise dem zu untersuchenden Objekt von mehreren Seiten beliebig angenähert werden, da das gefangene Objekt frei im Raum bewegt werden kann. Die gezielte biochemische Präparation des gefangenen Objektes eröffnet außerdem die Möglichkeit, die zu charakterisierenden Systeme, wie Makromoleküle oder Proteine, selektiv zu immobilisieren und diese dann gezielt in Kontakt zu bringen mit weiteren zu untersuchenden Molekülen. In dieser Arbeit werden lokale Viskositätsmessungen in Gegenwart von Grenzflächen durchgeführt. Eine weitere Fragestellung ist die Messung von Kräften an intrazellulären Systemen der Signalweiterleitung sowie das noch relativ unerforschte Gebiet der Kraftspektroskopie der Optischen Pinzette an lebenden Zellen. Vorrangigste Untersuchungsgebiete sind jedoch die mechanischen Eigenschaften von doppelsträngigen DNA-Molekülen (in Abhängigkeit von äußeren Parametern) und die Veränderung der Charakteristika in Abhängigkeit von schwach oder unspezifisch bindenden Liganden. Unterschiedlichste Bindungsmoden konnten identifiziert und differenziert werden und quantitative Aspekte der Elastizität jener Komplexe beschrieben werden. Die bislang nahezu kaum charakterisierte Kinetik der Bindungen jener Liganden an dsDNA stellte ein weiteres Untersuchungsgebiet dar. Dies ermöglichte wiederum Rückschlüsse auf konformative und zeitliche Änderungen der Bindung von Liganden an DNA

The cross-country validation of the WHO 5 well-being index with item response theory and the alignment procedure

The five-item World Health Organization Well-Being Index (WHO-5) is a frequently used brief stan- dard measure in large-scale cross-cultural clinical studies. Despite its frequent use, some psychometric questions remain that concern the choice of an adequate item response theory (IRT) model, the evaluation of reliability at important cutoffpoints, and most importantly the assessment of measurement invariance across countries. Data from the 6 th European Working Condition survey (2015) were used that collected nationally representative samples of employed and self-employed individuals ( N = 43,469) via computer-aided personal interviews across 35 European countries. An in-depth IRT analysis was conducted for each country, testing dif- ferent IRT assumptions (e.g., unidimensionality), comparing different IRT-models, and calculating reliabilities. Furthermore, measurement invariance analysis was conducted with the recently proposed alignment procedure. The graded response model fitted the data best for all countries. Furthermore, IRT assumptions were mostly fulfilled. The WHO-5 showed overall and at critical points high reliability. Measurement invariance anal- ysis revealed metric invariance but discarded scalar invariance across countries. Analysis of the test characteristic curves of the aligned graded response model indicated low levels of differential test functioning at medium levels of the WHO-5, but differential test functioning increased at more extreme levels. The current study has no external criterion (e.g., structured clinical interviews) to assess sensitivity and specificity of the WHO-5 as a depression screening-tool. The WHO-5 is a psychometrically sound measure. However, large-scale cross-cultural studies should employ a latent variable modeling approach that accounts for non-invariant parameters across countries (e.g., alignment)

Workplace bullying: Validation of a measurement and the role of competition, passive avoidant leadership style, psychological contract violation and basic need frustration.

Workplace bullying, mobbing or harassment describe a situation where an employee is the target of systematic mistreatment by other organizational members (i.e., colleagues, supervisors, subordinates) that may cause severe social, psychological and psychosomatic problems in the targeted employee. Since the appearance of the book “The harassed worker” by Brodsky (1976) and initial studies by Heinz Leymann (1986, 1990), workplace bullying research has developed into a huge and still massively growing research area that is conducted all over the globe. Especially, when related concepts are considered, a vast amount of studies have researched prevalence, risk factors, consequences, and, very recently, psychological mechanisms of workplace bullying exposure. A literature review revealed that existing workplace bullying exposure self-report inventories exhibit some weaknesses. Therefore, the first study (Chapter 2) aimed to develop a new short scale, the Luxembourg Workplace Mobbing Scale (LWMS) in three different language versions (i.e., Luxembourgish, French, German). Furthermore, it investigated the psychometric properties and the validity of this scale and examined if the three language versions exhibit measurement invariance. The LWMS revealed good psychometric properties in terms of its internal consistency and its factor structure. Furthermore, metric and partial scalar invariance across the three language versions could be established. Initial validation tests revealed high criterion validity of the LWMS. In line with recent workplace bullying exposure research, the LWMS was meaningfully linked with other working factors and measures of psychological health. The second study (Chapter 3) aimed to test the LWMS’s factor structure and measurement invariance across possible risk groups of bullying exposure (i.e., gender, age, and occupational groups). Moreover, based on recent theories and findings on workplace bullying the study aimed to further elucidate the LWMS’s nomological net with relevant psychological (i.e., psychological well-being, work engagement, sleeping hours, suicidal thoughts) and physiological health measures (i.e., physiological health problems, alcohol and smoking consumption, body mass index) as well as with important organizational criteria (i.e., work performance, turnover intention, absenteeism) and with self-labeling victim status. Evaluation of different measurement invariance models confirm metric and (partial) scalar invariance across all compared groups. Neither age, gender, nor the most frequent areas of occupation in Luxembourg represent important risk factors for workplace bullying exposure. Regarding criterion validity, with the exceptions of alcohol and smoking consumption, all proposed psychological and physiological health measures as well as organizational criteria are meaningfully associated with the LWMS. In summary, the LWMS is especially useful, when the identification of workplace bullying exposure risk groups or cross-cultural research is of concern. The third study (Chapter 4) aimed to test specific organizational risk factors of the occurrence of workplace bullying. Specifically, competition and passive avoidant leadership style were tested as risk factors of workplace bullying (exposure and perpetration) assessed with two assessment methods (behavioral experience and self-labeling method). Consistent with theoretical reasoning and prior research, results demonstrated that competition as well as passive avoidant leadership style are important risk factors of workplace bullying exposure. Moreover, results showed that the same effects showed up for perpetration. Even more interesting, passive avoidant leadership style acted as a moderator on the effect of competition on workplace bullying exposure. In line with theory, competition is stronger related to workplace bullying exposure, when passive avoidant leadership is high. Thus, passive avoidant leadership style can be considered a disruptive factor reinforcing the negative association with competition. Regarding workplace bullying perpetration the same moderation effect was only found for the self-labeled assessment method. The fourth study (Chapter 5) aimed to identify different psychological mechanisms (i.e., psychological contract violation and frustration of basic needs) that link being target of workplace bullying and health, attitudinal and behavioral outcomes. Furthermore, their relative impact and importance on different outcomes were highlighted. Psychological contract violation was an important mediator for decreased job satisfaction and higher turnover intentions, whereas frustration of autonomy mediated the effect between workplace bullying exposure and increased levels of burnout, frustration of competence mediated the effect of bullying exposure on decreased work performance and frustration of relatedness was strongly associated with decreased well-being and vigor. Results showed that feelings of psychological contract violation and frustration of basic needs accounted for unique variation in many outcome variables, pointing to the individual contribution of both psychological mechanisms. The present thesis deepens our understanding of the organizational circumstances under which workplace bullying is more likely and the psychological mechanisms that link the bullying exposure with several outcomes. These results can guide possible prevention and intervention strategies