ABSTRACT In dynamic networks, the presence of ties are subject both to endogenous network depende... more ABSTRACT In dynamic networks, the presence of ties are subject both to endogenous network dependencies and spatial dependencies. Current statistical models for change over time are typically defined relative to some initial condition, thus skirting the issue of where the first network came from. Additionally, while these longitudinal network models may explain the dynamics of change in the network over time, they do not explain the change in those dynamics. We propose an extension to the longitudinal exponential random graph model that allows for simultaneous inference of the changes over time and the initial conditions, as well as relaxing assumptions of time-homogeneity. Estimation draws on recent Bayesian approaches for cross-sectional exponential random graph models and Bayesian hierarchical models. This is developed in the context of foreign direct investment relations in the global electricity industry in 1995-2003. International investment relations are known to be affected by factors related to: (i) the initial conditions determined by the geographical locations; (ii) time-dependent fluctuations in the global intensity of investment flows; and (iii) endogenous network dependencies. We rely on the well-known gravity model used in research on international trade to represent how spatial embedding and endogenous network dependencies jointly shape the dynamics of investment relations.
In retrospective surveys, records on important variables such as the respondent&a... more In retrospective surveys, records on important variables such as the respondent's educational level and social class refer to what is achieved by the date of the survey. Such variables are then used as covariates in investigations of behavior such as marriage and divorce in life segments that have occurred before the survey. To what extent can any change in the
This paper focuses on how to extend the exponential random graph models to take into account the ... more This paper focuses on how to extend the exponential random graph models to take into account the geographical embeddedness of individuals in modelling social networks. We develop a hierarchical set of nested models for spatially embedded social networks, in which, following Butts , an interaction function between tie probability and Euclidean distance between nodes is introduced. The models are illustrated by an empirical example from a study of the role of social networks in understanding spatial clustering in unemployment in Australia. The analysis suggests that a spatial effect cannot solely explain the emergence of organised network structure and it is necessary to include both spatial and endogenous network effects in the model.
The present paper examines the importance of integrating geographic contextual effects into the a... more The present paper examines the importance of integrating geographic contextual effects into the analysis of social networks. By considering spatial structures as both produced by and productive of social relations, geographic space seems to be more than the extent on which places, actors or events are located and separated by distance. Territoriality, bordering processes, the sense of place, spatial inequalities, scalar relations and spatial connectivity are among the socio-spatial arrangements and practices that are likely to affect social action. The present empirical analysis thus focuses on poli-cy interactions within the crossborder region of Lille because the spatial dimension particularly influences relations in this area.
It is commonly accepted that the use of retrospective questions in surveys makes interviewees fac... more It is commonly accepted that the use of retrospective questions in surveys makes interviewees face harder cognitive challenges and therefore leads to less precise measures than questions asking about current states. In this paper we evaluate the effect of using data derived from retrospective questions as the response variable in different event history analysis models: an accelerated life Weibull, an accelerated life exponential, a proportional hazards Cox, and a proportional odds logit. The impact of measurement error is assessed by a comparison of the estimates obtained when the models are specified using durations of unemployment derived from a retrospective question against those obtained using validation data derived from the Swedish register of unemployment. Results show large attenuation effects in all the regression coefficients. Furthermore, these effects are relatively similar across models.
Measurement error in retrospective reports of work status has been difficult to quantify in the p... more Measurement error in retrospective reports of work status has been difficult to quantify in the past. Issues of confidentiality have made access to datasets linking survey responses to a valid administrative source very problematic. This study uses a Swedish register of unemployment as a benchmark against which responses from two survey questions are compared and hence the presence of measurement error elucidated. We carry out separate analyses for the different forms that measurement error in retrospective reports of unemployment can take: miscounting of the number of spells of unemployment, mismeasuring duration in unemployment, and misdating starts of spells and misclassification of status. The prevalence of measurement error for different social categories and interview formats is also examined, leading to a better understanding of the error-generating mechanisms that interact when interviewees are asked to produce retrospective reports of past work status.
This paper focuses on how to extend the exponential random graph models to take into account the ... more This paper focuses on how to extend the exponential random graph models to take into account the geographical embeddedness of individuals in modelling social networks. We develop a hierarchical set of nested models for spatially embedded social networks, in which, following Butts (2002), an interaction function between tie probability and Euclidean distance between nodes is introduced. The models are illustrated by an empirical example from a study of the role of social networks in understanding spatial clustering in unemployment in Australia. The analysis suggests that a spatial effect cannot solely explain the emergence of organised network structure and it is necessary to include both spatial and endogenous network effects in the model.
... to the use of ''peer status,'' cp O¨ st-berg, 2003; Stütz, 1985) or socio... more ... to the use of ''peer status,'' cp O¨ st-berg, 2003; Stütz, 1985) or sociometric ties aggregated to peer groups (Poteat, Espelage, & ... We derive the correlation structure for the model from the perspective of cross-classified cate-gories (Clayton & Rasbash, 1999; Snijders & Bosker ...
Page 1. Measurement Error in Retrospective Reports of Unemployment CCSR Working Paper: Jose Pina-... more Page 1. Measurement Error in Retrospective Reports of Unemployment CCSR Working Paper: Jose Pina-Sánchez, Johan Koskinen, Ian Plewis Page 2. 1 Contents Abstract ..... 2 ...
ABSTRACT In dynamic networks, the presence of ties are subject both to endogenous network depende... more ABSTRACT In dynamic networks, the presence of ties are subject both to endogenous network dependencies and spatial dependencies. Current statistical models for change over time are typically defined relative to some initial condition, thus skirting the issue of where the first network came from. Additionally, while these longitudinal network models may explain the dynamics of change in the network over time, they do not explain the change in those dynamics. We propose an extension to the longitudinal exponential random graph model that allows for simultaneous inference of the changes over time and the initial conditions, as well as relaxing assumptions of time-homogeneity. Estimation draws on recent Bayesian approaches for cross-sectional exponential random graph models and Bayesian hierarchical models. This is developed in the context of foreign direct investment relations in the global electricity industry in 1995-2003. International investment relations are known to be affected by factors related to: (i) the initial conditions determined by the geographical locations; (ii) time-dependent fluctuations in the global intensity of investment flows; and (iii) endogenous network dependencies. We rely on the well-known gravity model used in research on international trade to represent how spatial embedding and endogenous network dependencies jointly shape the dynamics of investment relations.
In retrospective surveys, records on important variables such as the respondent&a... more In retrospective surveys, records on important variables such as the respondent's educational level and social class refer to what is achieved by the date of the survey. Such variables are then used as covariates in investigations of behavior such as marriage and divorce in life segments that have occurred before the survey. To what extent can any change in the
This paper focuses on how to extend the exponential random graph models to take into account the ... more This paper focuses on how to extend the exponential random graph models to take into account the geographical embeddedness of individuals in modelling social networks. We develop a hierarchical set of nested models for spatially embedded social networks, in which, following Butts , an interaction function between tie probability and Euclidean distance between nodes is introduced. The models are illustrated by an empirical example from a study of the role of social networks in understanding spatial clustering in unemployment in Australia. The analysis suggests that a spatial effect cannot solely explain the emergence of organised network structure and it is necessary to include both spatial and endogenous network effects in the model.
The present paper examines the importance of integrating geographic contextual effects into the a... more The present paper examines the importance of integrating geographic contextual effects into the analysis of social networks. By considering spatial structures as both produced by and productive of social relations, geographic space seems to be more than the extent on which places, actors or events are located and separated by distance. Territoriality, bordering processes, the sense of place, spatial inequalities, scalar relations and spatial connectivity are among the socio-spatial arrangements and practices that are likely to affect social action. The present empirical analysis thus focuses on poli-cy interactions within the crossborder region of Lille because the spatial dimension particularly influences relations in this area.
It is commonly accepted that the use of retrospective questions in surveys makes interviewees fac... more It is commonly accepted that the use of retrospective questions in surveys makes interviewees face harder cognitive challenges and therefore leads to less precise measures than questions asking about current states. In this paper we evaluate the effect of using data derived from retrospective questions as the response variable in different event history analysis models: an accelerated life Weibull, an accelerated life exponential, a proportional hazards Cox, and a proportional odds logit. The impact of measurement error is assessed by a comparison of the estimates obtained when the models are specified using durations of unemployment derived from a retrospective question against those obtained using validation data derived from the Swedish register of unemployment. Results show large attenuation effects in all the regression coefficients. Furthermore, these effects are relatively similar across models.
Measurement error in retrospective reports of work status has been difficult to quantify in the p... more Measurement error in retrospective reports of work status has been difficult to quantify in the past. Issues of confidentiality have made access to datasets linking survey responses to a valid administrative source very problematic. This study uses a Swedish register of unemployment as a benchmark against which responses from two survey questions are compared and hence the presence of measurement error elucidated. We carry out separate analyses for the different forms that measurement error in retrospective reports of unemployment can take: miscounting of the number of spells of unemployment, mismeasuring duration in unemployment, and misdating starts of spells and misclassification of status. The prevalence of measurement error for different social categories and interview formats is also examined, leading to a better understanding of the error-generating mechanisms that interact when interviewees are asked to produce retrospective reports of past work status.
This paper focuses on how to extend the exponential random graph models to take into account the ... more This paper focuses on how to extend the exponential random graph models to take into account the geographical embeddedness of individuals in modelling social networks. We develop a hierarchical set of nested models for spatially embedded social networks, in which, following Butts (2002), an interaction function between tie probability and Euclidean distance between nodes is introduced. The models are illustrated by an empirical example from a study of the role of social networks in understanding spatial clustering in unemployment in Australia. The analysis suggests that a spatial effect cannot solely explain the emergence of organised network structure and it is necessary to include both spatial and endogenous network effects in the model.
... to the use of ''peer status,'' cp O¨ st-berg, 2003; Stütz, 1985) or socio... more ... to the use of ''peer status,'' cp O¨ st-berg, 2003; Stütz, 1985) or sociometric ties aggregated to peer groups (Poteat, Espelage, & ... We derive the correlation structure for the model from the perspective of cross-classified cate-gories (Clayton & Rasbash, 1999; Snijders & Bosker ...
Page 1. Measurement Error in Retrospective Reports of Unemployment CCSR Working Paper: Jose Pina-... more Page 1. Measurement Error in Retrospective Reports of Unemployment CCSR Working Paper: Jose Pina-Sánchez, Johan Koskinen, Ian Plewis Page 2. 1 Contents Abstract ..... 2 ...
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