(Forthcoming at the Journal of Public Administration Research and Theory, 2013)
Panel data analysis has become a popular tool for researchers in public policy and public administration. Combining information from both spatial and temporal dimensions, panel data allow researchers to use repeated observations of the same units (e.g. government agencies, public organizations, public managers, etc.), and could increase both quantity and quality of the empirical information. Nonetheless, practices of choosing different panel model specifications are not always guided by substantive considerations. Using a state-level panel data set related to public health administration as an example, I compare four categories of panel model specifications: (1) the fixed effects model, (2) the random effects model, (3) the random coefficients (heterogeneous-parameter model), and (4) linear dynamic models. I provide an overview of the substantive consideration relevant to different statistical specifications. I compare, furthermore, estimation results and discuss how these different model choices may lead to different substantive interpretations. Based on model comparisons, I demonstrate several potential problems of different panel models. I conclude with a discussion on how to choose among different models based on substantive and theoretical considerations.
(American Journal of Political Science 2011, With Christine S. Lipsmeyer)
At a time of mounting concern about how traditional welfare states will react to globalization, there has been increasing interest in specifying how global economic forces affect welfare policies in industrialized states. Building on theories from the political economy and comparative institutional literatures, we analyze the influence of an important aspect of globalization—the flow of immigration. Focusing on states in the European Union, we present a theoretical model that illustrates the interactive relationships between immigration, EU labor market integration, and domestic institutions. Our findings highlight how immigration in conjunction with domestic political institutions affects unemployment provisions, while labor market integrative forces remain in the background. The story of immigration and unemployment compensation in the EU is less about the opening of borders and the market forces of integration and more about the domestic political pressures.
Full Article in .pdf Format and Replication Materials
(Forthcoming at the American Journal of Public Health, with Breanca Thomas)
Objectives. We examine the association between school-based obesity policies, social capital, and self-reported weight-control behaviors among adolescents. We focused on how the collective roles of community and adopted policies affect gender groups differently.
Methods. We estimated state-level ecologic models using one-way random-effects SUR estimation based on panel data from 1991 to 2009. Multiplicative interaction terms were used to assess how social capital condition the effects of school-based obesity policies.
Results. More school-based obesity policies within active communities are mixed in improving weight-control behaviors. They increase both healthy and unhealthy weight-control behaviors among boys, but do not increase healthy weight-control behaviors among girls.
Conclusions. Social capital is an important contextual factor that conditions policy effectiveness at large scales. Heterogeneous behavioral responses were associated to both school-based obesity policies and social capital. The results suggest that building social capital and developing policy programs to balance outcomes for both gender groups may be challenging in managing childhood obesity.