Dynamic Effects of Trust and Cognitive Social Structures on Information Transfer Relationships

Changes in relationships are due to human actions. We assume that these human actions are functions of perceptions of a focal individual, but also the perceptions of other individuals who are part of the organizational and social environment. We hypothesize that perceptions based trust and perceptions of the structural environment individuals operate in affect relationship change more than the "actual" environment in which individuals operate. An empirically analysis shows the dynamic effects of perceptions on changes in two types of relationships, which are believed to be important in account management. We explore, 1, whether the levels of perceptions, and, 2, whether changes in perceptions affect relationship changes. For example, we consider the effects of the amount of trust as well as the change in the amount of trust one individual puts in another individual. We find that perceptions have more impact on relationship change than "actual" network variables have. Furthermore, the results show that it is useful to distinguish between level and change effects of perceptions.trust;dynamic cognitive social structures;network theory;relationship development

An Equilibrium-Correction Model for Dynamic Network Data

We propose a two-stage MRQAP to analyze dynamic network data, within the framework of an equilibrium-correction (EC) model. Extensive simulation results indicate practical relevance of our method and its improvement over standard OLS. An empirical illustration additionally shows that the EC model yields interpretable parameters, in contrast to an unrestricted dynamic model.cognitive social structures;consistent accuracy;network centrality;structural autocorrelation;two-stage equilibrium model

Koronare Herzerkrankung: Innovative Techniken und Strategien der interventionellen Koronardiagnostik und -therapie

Die PCI ist die am häufigsten an epikardialen Herzgefäßen durchgeführte Prozedur zur Behandlung der KHK. Bei Patienten mit therapierefraktärer Angina pectoris stellt die therapeutische Arteriogenese eine aussichtsreiche Therapieoption dar. Im Großtiermodell am Schwein werden mittels Micro-CT-Analyse präexistente Kollateralgefäße und mittels MRT deren funktionelle Bedeutung nachgewiesen. Ein minimalinvasives Tiermodell mit perkutan interventionell induziertem kontrollierten CTO-artigen Koronargefäßverschluss und seriellen Verlaufsbeobachtungen am gleichen Tier ist die Voraussetzung für die Beurteilung und Stimulation von Kollateralwachstum und der Entwicklung eines natürlichen Koronararterien-bypasses am menschlichen Herzen. Bei stabiler Angina pectoris ist die angiographische Beurteilung und Stenosegradeinschätzung von mittelgradigen Koronarstenosierungen nicht ausreichend. Die Bestimmung der FFR ist indiziert, um die hämodynamische Relevanz und Interventionsnotwendigkeit dieser Koronareinengungen beurteilen und nicht indizierte Revaskularisationsmaßnahmen ohne Nutzen für den Patienten abzuwenden zu können. Trotz Klasse IA Empfehlung der ESC ist die Implementierung der FFR-Index-Methode im klinischen Alltag aber unzureichend. IFR als leichter anzuwendende, kostengünstigere und für den Patienten weniger belastende Methode ist der FFR-Messung als gleichrangig anzusehen und kann als potentiell neuer Standard zu einer besseren Umsetzung und häufigeren leitliniengerechten Anwendung der funktionellen Beurteilung von Koronarstenosierungen in der Klinik führen. Bei indizierter PCI ermöglichen innovative Stenttechnologien bei gleicher Effektivität verglichen zu einem Standard-DES eine schnellere Stent-Einheilung mit verkürzter DAPT-Dauer und niedrigerem Blutungsrisiko. Das an mehr als 2500 Patienten prospektiv durchgeführte PF-SES Register belegt den Nutzen und Vorteil dieses polymerfreien Stents im unselektierten klinischen Alltag. Bei Hochrisikopulationen ist der PF-SES dem unbeschichteten BMS überlegen.This work explores innovative interventional catheterization techniques and strategies for coronary artery disease diagnosis and treatment focusing on clinical advances in coronary physiology assessment and stent technology as well as their impact on clinical efficiency and safety. This work also involves the implementation of a large animal model visualizing collateral vessel growth

New Rules for Corporate Governance in the United States And Germany - A Model for New Zealand?

This paper surveys the possibilities for implementing new rules for corporate governance in New Zealand. It focuses on the new rules issued in Germany (the German Code of Corporate Governance) and the United States (the Sarbanes-Oxley Act). The paper analyses both to find out which rules might be appropriate for New Zealand. It is argued that New Zealand needs to adopt a code of corporate governance in order to keep up with international developments, otherwise it risks repelling local investors and failing to attract international investors. It is concluded that most importantly New Zealand should adopt a principles-based "comply-or-explain" approach rather than strict rules, as it offers greater flexibility. The paper further concludes that many of the rules issued in Germany and the United States could improve corporate governance in New Zealand and hence should be implemented

Cracking the Code of Process Safety Culture with Organizational Network Analysis

Organizations in the chemical process industry invest considerable amounts of time and resources managing change and implementing best practices to maintain safe operations and achieve operational objectives. Consequently, most executives and senior managers responsible for performance rely on formal organizational structure to achieve these objectives. However, front line employees responsible for ensuring safe operation of hazardous chemical processes are often influenced more by the informal than the formal organization in their daily activities. The dynamics of informal networks among workers are critical determinants of strong operational discipline (OD), process safety culture, and business performance. Yet, organizational social networks are often overlooked or not well understood by management. We discuss how organizational network analysis (ONA) may improve our understanding of process safety culture. We also share results from our exploratory study that used a novel survey instrument to measure OD at the individual level in conjunction with a social network survey indicating interaction for the exchange of job task performance and process safety advice, respectively

Contrasting Multiple Social Network Autocorrelations for Binary Outcomes, With Applications To Technology Adoption

The rise of socially targeted marketing suggests that decisions made by consumers can be predicted not only from their personal tastes and characteristics, but also from the decisions of people who are close to them in their networks. One obstacle to consider is that there may be several different measures for "closeness" that are appropriate, either through different types of friendships, or different functions of distance on one kind of friendship, where only a subset of these networks may actually be relevant. Another is that these decisions are often binary and more difficult to model with conventional approaches, both conceptually and computationally. To address these issues, we present a hierarchical model for individual binary outcomes that uses and extends the machinery of the auto-probit method for binary data. We demonstrate the behavior of the parameters estimated by the multiple network-regime auto-probit model (m-NAP) under various sensitivity conditions, such as the impact of the prior distribution and the nature of the structure of the network, and demonstrate on several examples of correlated binary data in networks of interest to Information Systems, including the adoption of Caller Ring-Back Tones, whose use is governed by direct connection but explained by additional network topologies

Peer influence in the diffusion of iPhone 3G over a large social network

In this paper, we study the effect of peer influence in the diffusion of the iPhone 3G across a number of communities sampled from a large dataset provided by a major European Mobile carrier in one country. We identify tight communities of users in which peer influence may play a role and use instrumental variables to control for potential correlation between unobserved subscriber heterogeneity and friends' adoption. We provide evidence that the propensity of a subscriber to adopt increases with the percentage of friends who have already adopted. During a period of 11 months, we estimate that 14 percent of iPhone 3Gs sold by this carrier were due to peer influence. This result is obtained after controlling for social clustering, gender, previous adoption of mobile Internet data plans, ownership of technologically advanced handsets, and heterogeneity in the regions where subscribers move during the day and spend most of their evenings. This result remains qualitatively unchanged when we control for changes over time in the structure of the social network. We provide results from several policy experiments showing that, with this level of effect of peer influence, the carrier would have hardly benefitted from using traditional marketing strategies to seed the iPhone 3G to benefit from viral marketing.info:eu-repo/semantics/publishedVersio

Transitivity correlation:A descriptive measure of network transitivity

This paper proposes that common measures for network transitivity, based on the enumeration of transitive triples, do not reflect the theoretical statements about transitivity they aim to describe. These statements are often formulated as comparative conditional probabilities, but these are not directly reflected by simple functions of enumerations. We think that a better approach is obtained by considering the probability of a tie between two randomly drawn nodes, conditional on selected features of the network. Two measures of transitivity based on correlation coefficients between the existence of a tie and the existence, or the number, of two-paths between the nodes are developed, and called "Transitivity Phi" and "Transitivity Correlation." Some desirable properties for these measures are studied and compared to existing clustering coefficients, in both random (Erdos-Renyi) and in stylized networks (windmills). Furthermore, it is shown that in a directed graph, under the condition of zero Transitivity Correlation, the total number of transitive triples is determined by four underlying features: size, density, reciprocity, and the covariance between in- and outdegrees. Also, it is demonstrated that plotting conditional probability of ties, given the number of two-paths, provides valuable insights into empirical regularities and irregularities of transitivity patterns

Dynamic Effects of Trust and Cognitive Social Structures on Information Transfer Relationships

Changes in relationships are due to human actions. We assume that these human actions are functions of perceptions of a focal individual, but also the perceptions of other individuals who are part of the organizational and social environment. We hypothesize that perceptions based trust and perceptions of the structural environment individuals operate in affect relationship change more than the "actual" environment in which individuals operate. An empirically analysis shows the dynamic effects of perceptions on changes in two types of relationships, which are believed to be important in account management. We explore, 1, whether the levels of perceptions, and, 2, whether changes in perceptions affect relationship changes. For example, we consider the effects of the amount of trust as well as the change in the amount of trust one individual puts in another individual. We find that perceptions have more impact on relationship change than "actual" network variables have. Furthermore, the results show that it is useful to distinguish between level and change effects of perceptions