48,622 research outputs found

    Market integration reduces kin density in women’s ego-networks in rural Poland

    No full text

    The embeddedness of organizational performance: multiple membership multiple classification models for the analysis of multilevel networks

    Get PDF
    We present a Multiple Membership Multiple Classification (MMMC) model for analysing variation in the performance of organizational sub-units embedded in a multilevel network. The model postulates that the performance of organizational sub-units varies across network levels defined in terms of: (i) direct relations between organizational sub-units; (ii) relations between organizations containing the sub-units, and (iii) cross-level relations between sub-units and organizations. We demonstrate the empirical mer- its of the model in an analysis of inter-hospital patient mobility within a regional community of health care organizations. In the empirical case study we develop, organizational sub-units are departments of emergency medicine (EDs) located within hospitals (organizations). Networks within and across levels are delineated in terms of patient transfer relations between EDs (lower-level, emergency transfers), hospitals (higher-level, elective transfers), and between EDs and hospitals (cross-level, non-emergency transfers). Our main analytical objective is to examine the association of these interdependent and par- tially nested levels of action with variation in waiting time among EDs – one of the most commonly adopted and accepted measures of ED performance. We find evidence that variation in ED waiting time is associated with various components of the multilevel network in which the EDs are embedded. Before allowing for various characteristics of EDs and the hospitals in which they are located, we find, for the null models, that most of the network variation is at the hospital level. After adding these characteris- tics to the model, we find that hospital capacity and ED uncertainty are significantly associated with ED waiting time. We also find that the overall variation in ED waiting time is reduced to less than a half of its estimated value from the null models, and that a greater share of the residual network variation for these models is at the ED level and cross level, rather than the hospital level. This suggests that the covari- ates explain some of the network variation, and shift the relative share of residual variation away from hospital networks. We discuss further extensions to the model for more general analyses of multilevel network dependencies in variables of interest for the lower level nodes of these social structures

    The impact of metropolitan structure on commute behavior in the Netherlands: a multilevel approach

    Get PDF
    The effect of decentralization of land uses on travel behavior remains an unresolved issue in the academic literature. Some US researchers argue that a tendency towards polycentrism is associated with decreasing commute times and distances. Others have, however, suggested and shown the opposite commute times and distances tend to be longer in polycentric than in monocentric urban areas. Using this controversy as a starting point, we analyse how monocentric and polycentric urban structures affect commuting in the Netherlands with data from the 1998 National Travel Survey. Four kinds of urban systems are distinguished: one monocentric and three polycentric systems. In contrast to most previous work, we use multilevel regression analysis to take adequate account of the effects of individual and household attributes. The results indicate that urban structure influences most dimensions of commuting considered here. Yet, individual and household level variables are more important determinants than characteristics of the residential and workplace environment. Gender, household type and their interaction effects remain important determinants of commute behavior in the Netherlands; particularly women in two-earner households commute less than average. Education and income are both positively related to the amount of commuting. Further, the effects of mono- and polycentrism on commuting are more complicated than the literature makes us believe. When individual and household level factors are taken account of, polycentrism does not always result in more efficient commute patterns than monocentric urban structures: in most polycentric urban areas commute distances and times are longer than in monocentric ones. Only when polycentric regions consist of several relatively independent and self-contained development nodes are commute distances shorter than elsewhere. Commute times are in that case comparable to those in monocentric urban areas. The impact of urban structure disappears when commute time is related to the time spent on work activities; the ratio between commute time and work duration is not much affected by the type of urban system in which workers reside. The fact that commute times and distances are not lower in polycentric urban areas may be attributed to the specific situation in the Netherlands: strong spatial planning policies may have obstructed the relocation of employment and housing in close proximity of each other. However, the longer commute in most policentric regions may also indicate that workers and their households not always behave as urban economic theory predicts. In any case, the results show that it is necessary to distinguish several types of polycentric systems instead of merely using a dichotomy of monocentric and polycentric in the analysis of commuting.

    Do cyber-birds flock together? Comparing deviance among social network members of cyber-dependent offenders and traditional offenders

    No full text
    The distinct setting in which cyber-dependent crime takes place may reduce the similarity in the deviance of social network members. We test this assumption by analysing the deviance of the most important social contacts of cyber-dependent offenders and traditional offenders in the Netherlands (N = 344 offenders; N = 1131 social contacts). As expected, similarity in deviance is weaker for cyber-dependent crime. Because this is a strong predictor of traditional offending, this has important implications for criminological research and practice. Additionally, for both crime types the offending behaviour of a person is more strongly linked to the deviance of social ties if those ties are of the same gender and age, and if the offender has daily contact with them. Implications and future criminological research suggestions are discussed

    Change and instability

    Get PDF
    This article examines changes in network structure using data on conversational networks from the 1998 and 2001 rounds of the Malawi Diffusion and Ideation Change project. The principal aims are to show that network structure can change significantly in relatively short periods - in particular at times of rapid social change - and that multilevel analysis is an effective way to explore these types of changes. The article demonstrates that: (i) conversations about AIDS are increasingly occurring within all demographic groups in rural Malawi, (ii) AIDS-related conversational networks have diversified, (iii) there is significant village-level variance in characteristics of reported network partners, but it is a minimal source of total variance in such characteristics, and (iv) that there is significant covariance between the estimated residuals associated with key predictors of size of AIDS- related conversational networks.AIDS/HIV, interaction, Malawi, multilevel, networks

    Regional characteristics, opportunity perception and entrepreneurial activities

    Get PDF
    This paper seeks to better understand the link between regional characteristics and individual entrepreneurship. We combine individual-level GEM data for Western Germany with regional-level data, using multi-level analysis to test our hypotheses. We find no direct link between regional knowledge creation, the economic context and an entrepreneurial culture on the one side and individual business start-up intentions and start-up activity on the other side. However our findings point to the importance of an indirect effect of regional characteristics as knowledge creation, the economic context and an entrepreneurial culture have an effect on the individual perception of founding opportunities which in turn predicted start-up intentions and activity

    The Synthesis of Cyclic Combinatorial Circuits

    Get PDF
    To be added

    Anosognosia for hemiplegia as a tripartite disconnection syndrome

    Get PDF
    © 2019 Pacella et al. This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited.The syndrome of Anosognosia for Hemiplegia (AHP) can provide unique insights into the neurocognitive processes of motor awareness. Yet, prior studies have only explored predominately discreet lesions. Using advanced structural neuroimaging methods in 174 patients with a right-hemisphere stroke, we were able to identify three neural systems that contribute to AHP, when disconnected or directly damaged: the (i) premotor loop (ii) limbic system, and (iii) ventral attentional network. Our results suggest that human motor awareness is contingent on the joint contribution of these three systems.Peer reviewedFinal Published versio
    corecore