Ethno-Caste Influences on Migration Rates and Destinations.

While studies commonly show differences in out-migration between ethnic groups, ethnicity most often features no more than a side note in the emigration literature, and we have very little insight about why people from different ethnic groups migrate at different rates. Understanding ethnic differences in migration rates and destination choice has important implications for the present-day and future potential for either dampening or exacerbating ethnic discrimination and opportunity structures. Building on existing migration theory, we identify three possible mechanisms through which ethnicity might influence out-migration rates and destination choice: human and economic capital, contemporary discrimination, and historical legacies that are perpetuated through social networks. Our empirical investigation uses longitudinal panel survey data from Nepal and we find that all three of these mechanisms likely influence out-migration and destinations of the five major ethno-caste groups. However, we show that historical legacy and human and economic capital emerge as the key drivers of ethnic differences in out-migration here. We discuss what these results mean for migration studies as well as the potential for the institution of migration to affect patterns of ethno-caste-based disadvantage in Nepal. The theoretical basis and empirical evidence from our study also suggest ways to understand the reasoning for and consequence of ethnic and racial differentials in migration patterns in other areas of the world.

When does Social Capital Matter for Migration? A Study of Networks, Brokers, and Migrants in Nepal.

The study of social capital has been one of the strongest areas of recent advance in migration research, but there are still many questions about how it works and why it has varying effects in studies of different places. In this article, we address the contextual variation in social capital's effects on migration by considering migration brokers. We argue that destinations for which migration is logistically difficult to arrange give rise to brokerage industries and hypothesize that brokers in turn substitute for the informational capital typically provided by social networks. Our empirical tests in Nepal support this narrative, showing that social networks matter for migration to destinations where brokers are not available and have little discernible effect on migration to brokered destinations. Our results suggest that migration research should consider the growing role of brokerage agencies, that theorizations of social capital more broadly must contend with how it is delimited by brokers, and that social scientists might also consider other consequences that can arise from these migration brokers that are increasingly common in many countries and provide a marketized replacement for social capital in some cases.

Spatial and Temporal Dimensions of Weather Shocks and Migration in Nepal.

Research shows that environmental shocks can influence migration. However, studies vary widely in the shocks and type of migration measured, the context, and the strength and direction of environmental effects. In addition, existing theories provide opposing predictions for this relationship. There is a clear need for further theoretical development in the climate-migration literature. This study, in rural Nepal, examines four types of weather shocks, over various time frames, on four types of migration. Results suggest that the most substantial influence of weather shocks is not in a wholesale increase or decrease in migration. Instead, weather shocks are related to changes in the type of migration used, resulting in less long-term and more short-term migrations in the population. We use the Ready-Willing-and-Able perspective to make sense of these patterns.

Influences of Material Aspirations on Migration.

In this article, we investigate the influences of material aspirations on migration in Nepal, positing that material aspirations may have important influences on decisions to migrate and where to locate. We discuss a theoretical model explaining how these aspirations might be key influences in the migration decision. Using detailed continuous migration histories from the 2008-2012 Chitwan Valley Family Study, we estimate logistic and alternative-specific conditional logit models to examine how material aspirations in Nepal influence migration rates and destinations. Our empirical analyses provide strong evidence that material aspirations have large effects on overall rates of migration and affect destination-specific migration rates, particularly for relatively wealthy Western and Asian destinations. We also show an interaction effect between material aspirations and destination-specific expected earnings in influencing people's migration choices. It is the people with high aspirations who migrate to destinations with high earning potentials.

Fear of violence during armed conflict: Social roles and responsibilities as determinants of fear.

This article investigates the prevalence and determinants of fear as a consequence of living through armed conflict. We use survey data from Nepal during the armed conflict (1996-2006) to examine how trauma, sex and gender, age, marriage, and household size affect fear of violence. We also disaggregate types of worry, and find substantial variance on whether respondents were more concerned about livelihood consequences of conflict than physical danger. We supplement quantitative analyses with discussion of in-depth interviews from the study area on these same topics. Overall, our results highlight the enduring impact of gender roles in Nepal and that conflict might disproportionately affect those who are already vulnerable and have greater social responsibilities. This article provides a unique comparison between fear of violence during armed conflict in a low-income country to the fear of crime literature based in high-income countries.

Climate Shocks and Migration: An Agent-Based Modeling Approach.

This is a study of migration responses to climate shocks. We construct an agent-based model that incorporates dynamic linkages between demographic behaviors, such as migration, marriage, and births, and agriculture and land use, which depend on rainfall patterns. The rules and parameterization of our model are empirically derived from qualitative and quantitative analyses of a well-studied demographic field site, Nang Rong district, Northeast Thailand. With this model, we simulate patterns of migration under four weather regimes in a rice economy: 1) a reference, 'normal' scenario; 2) seven years of unusually wet weather; 3) seven years of unusually dry weather; and 4) seven years of extremely variable weather. Results show relatively small impacts on migration. Experiments with the model show that existing high migration rates and strong selection factors, which are unaffected by climate change, are likely responsible for the weak migration response.

Associations between the social organization of communities and psychiatric disorders in rural Asia.

PURPOSE: We provide rare evidence of factors producing psychiatric variation in a general population sample from rural South Asia. The setting is particularly useful for demonstrating that variations in the social organization of communities, often difficult to observe in rich countries, are associated with important variations in mental health. METHODS: Clinically validated survey measures are used to document variation in psychiatric disorders among 401 adults. This sample is chosen from a systematic sample of the general population of rural Nepal, in a community-level-controlled comparison design. Multilevel logistic regression is used to estimate multivariate models of the association between community-level nonfamily social organization and individual-level psychiatric disorders. RESULTS: Schools, markets, health services and social support groups each substantially reduce the odds of depression, post-traumatic stress disorder (PTSD), intermittent explosive disorder and anxiety disorders. Associations between schools, health services and social support groups and depression are statistically significant and independent of each other. The association between access to markets and PTSD is statistically significant and independent of other social organization and support groups. CONCLUSIONS: Community integration of some nonfamily social organizations promotes mental health in ways that may go unobserved in settings with many such organizations. More research on the mechanisms producing these associations is likely to reveal potential avenues for public policy and programs to improve mental health in the general population.

Changing crops in response to climate: virtual Nang Rong, Thailand in an agent based simulation.

The effects of extended climatic variability on agricultural land use were explored for the type of system found in villages of northeastern Thailand. An agent based model developed for the Nang Rong district was used to simulate land allotted to jasmine rice, heavy rice, cassava, and sugar cane. The land use choices in the model depended on likely economic outcomes, but included elements of bounded rationality in dependence on household demography. The socioeconomic dynamics are endogenous in the system, and climate changes were added as exogenous drivers. Villages changed their agricultural effort in many different ways. Most villages reduced the amount of land under cultivation, primarily with reduction in jasmine rice, but others did not. The variation in responses to climate change indicates potential sensitivity to initial conditions and path dependence for this type of system. The differences between our virtual villages and the real villages of the region indicate effects of bounded rationality and limits on model applications.

How community organizations moderate the effect of armed conflict on migration in Nepal.

This study analyses micro-level variability in migration during armed conflict in Nepal. The analysis is based on a multi-dimensional model of individual out-migration that examines the economic, social, and political consequences of conflict and how community organizations condition the experience of these consequences and systematically alter migration patterns. Detailed data on violent events and individual behaviour during the Maoist insurrection in Nepal and multi-level event-history analysis were used to test the model. The results indicate that community organizations reduced the effect of conflict on out-migration by providing resources that helped people cope with danger, as well as with the economic, social, and political consequences of the conflict. The evidence suggests that the conflict caused the population to be systematically redistributed in a way that will probably affect its future socio-demographic composition--the extent of the redistribution depending on the resources available in each community.

Strategies for origin-based surveying of international migrants.

This paper addresses methodological challenges of investigations of international migration, including difficulties in obtaining information about representative samples of migrants and both their origin and destination location. Our project used an origin-based sample with a destination focused survey and interviewed 91% of migrants from a community in Nepal to any destination and shares techniques employed. Our procedures and high response rate constitute a significant improvement in survey methods that permit the creation of unbiased data on migrants and allow the study of migration in conjunction with origin communities.

Mixed and Complex Mixed Migration during Armed Conflict: Multidimensional Empirical Evidence from Nepal.

Historically, legal, policy, and academic communities largely ascribed to a dichotomy between forced and voluntary migration, creating a black and white vision that was convenient for legal and policy purposes. More recently, discussions have begun addressing the possibility of mixed migration, acknowledging that there is likely a wide continuum between forced and voluntary, and most migrants likely move with some amount of compulsion and some volition, even during armed conflict. While the mixed migration hypothesis is well-received, empirical evidence is disparate and somewhat blunt at this point. In this article, I contribute a direct theoretical and causal pathway discussion of mixed migration. I also propose the complex mixed migration hypothesis, which argues that not only do non-conflict related factors influence migration during conflict, but they do so differently than during periods of relative peace. I empirically test both hypotheses in the context of the recent armed conflict in Nepal. Using detailed survey data and event history models, results provide strong evidence for both mixed migration and complex mixed migration during conflict hypotheses. These hypotheses and evidence suggest that armed conflict might have substantial impacts on long-term population growth and change, with significant relevance in both academic and policy spheres.

Spatiotemporal detection of unusual human population behavior using mobile phone data.

With the aim to contribute to humanitarian response to disasters and violent events, scientists have proposed the development of analytical tools that could identify emergency events in real-time, using mobile phone data. The assumption is that dramatic and discrete changes in behavior, measured with mobile phone data, will indicate extreme events. In this study, we propose an efficient system for spatiotemporal detection of behavioral anomalies from mobile phone data and compare sites with behavioral anomalies to an extensive database of emergency and non-emergency events in Rwanda. Our methodology successfully captures anomalous behavioral patterns associated with a broad range of events, from religious and official holidays to earthquakes, floods, violence against civilians and protests. Our results suggest that human behavioral responses to extreme events are complex and multi-dimensional, including extreme increases and decreases in both calling and movement behaviors. We also find significant temporal and spatial variance in responses to extreme events. Our behavioral anomaly detection system and extensive discussion of results are a significant contribution to the long-term project of creating an effective real-time event detection system with mobile phone data and we discuss the implications of our findings for future research to this end.

Measures of Human Mobility Using Mobile Phone Records Enhanced with GIS Data.

In the past decade, large scale mobile phone data have become available for the study of human movement patterns. These data hold an immense promise for understanding human behavior on a vast scale, and with a precision and accuracy never before possible with censuses, surveys or other existing data collection techniques. There is already a significant body of literature that has made key inroads into understanding human mobility using this exciting new data source, and there have been several different measures of mobility used. However, existing mobile phone based mobility measures are inconsistent, inaccurate, and confounded with social characteristics of local context. New measures would best be developed immediately as they will influence future studies of mobility using mobile phone data. In this article, we do exactly this. We discuss problems with existing mobile phone based measures of mobility and describe new methods for measuring mobility that address these concerns. Our measures of mobility, which incorporate both mobile phone records and detailed GIS data, are designed to address the spatial nature of human mobility, to remain independent of social characteristics of context, and to be comparable across geographic regions and time. We also contribute a discussion of the variety of uses for these new measures in developing a better understanding of how human mobility influences micro-level human behaviors and well-being, and macro-level social organization and change.

Migrant Values and Beliefs: How Are They Different and How Do They Change?

This is a study of the values of migrants. We examine processes of selection-how values affect migration-and adaptation-how migration influences value changes. Empirical analyses use a unique collection of data that combines detailed information on values from a representative sample of non-migrants in Nepal with a representative sample of Nepali migrants living in the Persian Gulf. Results suggest that migrants were selected from those who were more materialistic, less committed to religion and more family-oriented. In terms of adaptation, our results are consistent with the idea that migrants become more religious, less committed to historical Nepali values, and change ideas about family-orientation in mixed ways. Thus, we find that value adaptations of migrants are complex processes that could have immense impacts on ideational diffusion around the world.

Gender, traumatic events, and mental health disorders in a rural Asian setting.

Research shows a strong association between traumatic life experience and mental health and important gender differences in that relationship in the western European Diaspora; but much less is known about these relationships in other settings. We investigate these relationships in a poor rural Asian setting that recently experienced a decade-long armed conflict. We use data from 400 adult interviews in rural Nepal. The measures come from World Mental Health survey instruments clinically validated for this study population to measure depression, posttraumatic stress disorder, and intermittent explosive disorder. Our results demonstrate that traumatic life experience significantly increases the likelihood of mental health disorders in this setting, and that these traumatic experiences have a larger effect on the mental health of women than men. These findings offer important clues regarding the potential mechanisms producing gender differences in mental health in many settings.

Collecting Survey Data during Armed Conflict.

Surveys provide crucial information about the social consequences of armed conflict, but armed conflict can shape surveys in ways that limit their value. We use longitudinal survey data from throughout the recent armed conflict in Nepal to investigate the relationship between armed conflict events and survey response. The Chitwan Valley Family Study (CVFS) provides a rare window into survey data collection through intense armed conflict. The CVFS data reveal that with operational strategies tailored to the specific conflict, duration of the panel study is the main determinant of attrition from the study, just as in most longitudinal studies outside of conflict settings. Though minor relative to duration, different dimensions of armed conflict can affect survey response in opposing directions, with bombings in the local area reducing response rates but nationwide political events increasing response rates. This important finding demonstrates that survey data quality may be affected differently by various dimensions of armed conflict. Overall, CVFS response rates remained exceptionally high throughout the conflict. We use the CVFS experience to identify principles likely to produce higher quality surveys during periods of generalized violence and instability.

A micro-level event-centered approach to investigating armed conflict and population responses.

In this article, we construct and test a micro-level event-centered approach to the study of armed conflict and behavioral responses in the general population. Event-centered approaches have been successfully used in the macro-political study of armed conflict but have not yet been adopted in micro-behavioral studies. The micro-level event-centered approach that we advocate here includes decomposition of a conflict into discrete political and violent events, examination of the mechanisms through which they affect behavior, and consideration of differential risks within the population. We focus on two mechanisms: instability and threat of harm. We test this approach empirically in the context of the recent decade-long armed conflict in Nepal, using detailed measurements of conflict-related events and a longitudinal study of first migration, first marriage, and first contraceptive use. Results demonstrate that different conflict-related events independently shaped migration, marriage, and childbearing and that they can simultaneously influence behaviors in opposing directions. We find that violent events increased migration, but political events slowed migration. Both violent and political events increased marriage and contraceptive use net of migration. Overall, this micro-level event-centered approach yields a significant advance for the study of how armed conflict affects civilian behavioral responses.