Jakub Bijak
Biographic Data
| ID | 208559 |
|---|---|
| NAME | Jakub Bijak |
| GIVEN NAMES | Jakub |
| FAMILY NAME | Bijak |
| SIGNATURE | BIJAK J |
| AFFILIATIONS | University of Southampton |
| ORCID | 0000-0002-2563-5040 |
| VERIFIED | Yes |
| TOTAL WORKS | 32 |
| TOTAL CITATIONS | 150 |
| AUTHOR COUNT | 31 |
| EDITOR COUNT | 1 |
| FIRST PUBLICATION YEAR | 2005 |
| LATEST PUBLICATION YEAR | 2026 |
| H-INDEX | 8 |
Eliciting Utility Functions for International Migration Decisions
Migration is a highly complex and uncertain process that has the potential to have large impacts on societies around the world. One key driver of this complexity and uncertainty is the autonomous agency of the actors involved, particularly the decision‐making processes of potential migrants. Most theories and models rely on simplistic decision rules or a decision‐making process that assumes rational agents. However, a considerable body of researc…
Can Incorporating Parity Information Improve the Reliability of Completed Cohort Fertility Projections? Insights From a Bayesian Generalized Additive Model Approach
Fertility projections inform population projections and are used to plan for the future provision of vital services such as maternity care and schooling. Existing fertility forecasting models tend to use aggregate births data indexed by age and time alone, thereby neglecting to include information about parity, that is, the number of previous live-born children. This omission risks ignoring a crucial mechanism of fertility dynamics. We propose a …
Probabilistic projections of distributions of kin over the life course
BACKGROUNDMathematical kinship demography is an expanding area of research.Recent papers have explored the expected number of kin a typical individual should experience.Despite the uncertainty of the future number and distributions of kin, just one paper investigates it. OBJECTIVEWe aim to develop a new method for obtaining the probability that a typical population member experiences one or more of some kin at any age through the life course. MET…
Assessing Timely Migration Trends Through Digital Traces: A Case Study of the UK Before Brexit
Digital trace data presents an opportunity for promptly monitoring shifts in migrant populations. This contribution aims to determine whether the number of European migrants in the United Kingdom (UK) declined between March 2019 and March 2020, using weekly estimates derived from the Facebook Advertising Platform. The collected data is disaggregated according to age, level of education, and country of origin. To examine the fluctuation in the num…
From Uncertainty to Policy: A Guide to Migration Scenarios
This is an open access title available under the terms of a CC BY-NC-ND 4.0 License. It is free to read, download and share on Elgaronline.com. This unique book provides a practical and interdisciplinary blueprint for determining quantitative scenarios of future international migration. Focusing on complexity and uncertainty as the defining challenges of migration, it explores how scenario building can be used to inform and underpin effective mig…
Exploring the Potential of Using a Text-Based Game to Inform Simulation Models of Risky Migration Decisions
Background In this paper, we explore the potential of games to collect empirical data for informing agent-based simulation models of migration. To examine the usefulness of game-based approaches, we conducted a simple, yet carefully designed psychological experiment. Methods In a preregistered study, we used a novel, immersive experimental setting to investigate the risky migration decisions made by migrants and non-migrants. Participants (284 mi…
A Fast Embedded Language for Continuous-Time Agent-Based Simulation
In agent-based simulation methods and applications, discrete timestep approaches prevail. To support continuous-time agent-based simulation, we analyze how methods for simulating population-based Con-tinu-ous-Time Markov Chains (CMTCs) can be adopted and derive implications for the concrete realization. To corroborate our findings, we develop an efficient internal domain-specific language (DSL) based on ML3, a modeling language for linked lives i…
European migration governance in the context of uncertainty
Migration inherently embodies uncertainty and dynamism, eluding precise conceptualization, definition and measurement. Embedded within intricate migration driver environments and shaped by the diverse agency of actors involved—prospective migrants, intermediaries and policymakers—migration defies easy prediction and effective policy response. This inherent complexity within international migration flows poses immediate and long‐term governance ch…
From Conflict Zones to Europe: Syrian and Afghan Refugees’ Journeys, Stories, and Strategies
This article explores the journeys of Syrian and Afghan refugees to Europe, looking at two of the largest and politically most salient flows of asylum seekers during the 2010s. Following political disturbances in their home countries, millions of Syrians and Afghans have been forcibly displaced or had to seek safety elsewhere. In search of protection for themselves and their families, some of them had to cross multiple borders to reach European d…
Toward an Early Warning System for Monitoring Asylum-Related Migration Flows in Europe
Asylum-related migration is highly complex, uncertain, and volatile, which precludes using standard model-based predictions to inform policy and operational decisions. At the same time, asylum's potentially high societal impacts on receiving countries and the resource implications of asylum processes call for more proactive approaches for assessing current and future migration flows. In this article, we propose an alternative approach to asylum m…
A Framework for Estimating Migrant Stocks Using Digital Traces and Survey Data: An Application in the United Kingdom
An accurate estimation of international migration is hampered by a lack of timely and comprehensive data, and by the use of different definitions and measures of migration in different countries. In an effort to address this situation, we complement traditional data sources for the United Kingdom with social media data: our aim is to understand whether information from digital traces can help measure international migration. The Bayesian framewor…
Paleodemographic analysis of age at death for a population of Black Sea Scythians: An exploration by using Bayesian methods
OBJECTIVES: Studies of the demography of past populations involving deterministic life tables can be criticized for ignoring the errors of estimation. Bayesian methods offer an alternative, by focusing on the uncertainty of the estimates, although their results are often sensitive to the choice of prior distributions. The aim of this study is to explore a range of Bayesian methods for estimating age at death for a population of nomadic warriors-S…
Migration Decision-Making and Its Key Dimensions
Migration decisions are made in the context of personal needs and desires, and the individuals making these decisions face uncertain outcomes. Information about future opportunities is incomplete, and whether migration turns out to be a personal success or failure depends mostly on circumstances that are ex ante unknown and ex post not fully under the control of the individuals who migrate. This article elaborates on four dimensions of the comple…
Methodological Investigations in Agent-Based Modelling: With Applications for the Social Sciences
Agent-Based Modelling; ABM; Artificial Intelligence; AI; Computational social science; Social simulation; Population sciences
Streamlining Simulation Experiments with Agent-Based Models in Demography
In the last decade, the uptake of agent-based modeling in demography and other population sciences has been slowly increasing. Still, in such areas, where traditional data-driven, statistical approaches prevail, the hypothesis-driven design of agent-based models leads to questioning the validity of these models. Consequently, suitable means to increase the confidence into models and simulation results are required. To that end, explicit, replicab…
Model-Based Demography: Essays on Integrating Data, Technique and Theory
Book review of Model-Based Demography: Essays on Integrating Data, Technique and Theory. 2018. By THOMAS K. BURCH. Demographic Research Monographs Series. Cham: Springer. Pp. xviii+200. Open access (online) / £44.99 (hardcover). ISBN: 978-3-319-65433-1
Choosing the choice: Reflections on modelling decisions and behaviour in demographic agent-based models
This paper investigates the issues associated with choosing appropriate models of choice for demographic agent-based models. In particular, we discuss the importance of context, time preference, and dealing with uncertainty in decision modelling, as well as the heterogeneity between agents in their decision-making strategies. The paper concludes by advocating empirically driven, modular, and multi-model approaches to designing simulations of huma…
The science of choice: An Introduction
In October 2015, around 30 scholars convened at the Max Planck Institute for Demographic Research (MPIDR) in Rostock to discuss: (a) how individuals and families make decisions about marriage, chil
Warriors Die Young: Increased Mortality in Early Adulthood of Scythians from Glinoe, Moldova, Fourth through Second Centuries bc
Scythians were nomadic groups, playing a dominant role on the Eurasian steppes in the Early Iron Age according to many archaeological and historical sources. In this paper, we aim at assessing demographic features and dynamics of a Scythian population from the Black Sea region. We hypothesise that they differed from other societies not only in terms of culture, but also demography: their fertility was lower, and life expectancy higher than in oth…
Bayesian demography 250 years after Bayes
Bayesian statistics offers an alternative to classical (frequentist) statistics. It is distinguished by its use of probability distributions to describe uncertain quantities, which leads to elegant solutions to many difficult statistical problems. Although Bayesian demography, like Bayesian statistics more generally, is around 250 years old, only recently has it begun to flourish. The aim of this paper is to review the achievements of Bayesian de…
Welfare participation: A comparison between immigrants and natives in the United Kingdom
European migration is a hotly debated topic in the United Kingdom. Using the Labour Force Survey data for 2012 this study analyses benefit claims among Central and Eastern European immigrants, immigrants from the old European Union member states and UK natives. Results of logistic regression modelling show that, compared to natives, social benefit claims are higher among immigrants from the eight Eastern European countries that became member stat…
Bayesian Population Forecasting: Extending the Lee-Carter Method
In this article, we develop a fully integrated and dynamic Bayesian approach to forecast populations by age and sex. The approach embeds the Lee-Carter type models for forecasting the age patterns, with associated measures of uncertainty, of fertility, mortality, immigration, and emigration within a cohort projection model. The methodology may be adapted to handle different data types and sources of information. To illustrate, we analyze time ser…
Forecasting Scottish Migration in the Context of the 2014 Constitutional Change Debate
Migration to and from Scotland might be affected by the outcome of the 2014 Scottish referendum on the constitutional future of the United Kingdom. This potential change in migration has not been thoroughly analysed to date. The aim of this paper is thus to present a set of predictions of the possible effects of Scottish independence on internal and international migration. In particular, different sources of uncertainty of future migration flows…
Quantifying paradigm change in demography
Demography is a uniquely empirical research area amongst the social sciences. We posit that the same principle of empiricism should be applied to studies of the population sciences as a discipline, contributing to greater self-awareness amongst its practit
When Demography Met Social Simulation: A Tale of Two Modelling Approaches
In this paper we present an agent-based model of a human population, designed to illustrate the potential synergies between demography and agent-based social simulation. In the modelling process, we take advantage of the perspectives of both disciplines: demography being more focused on matching statistical models to empirical data, and social simulation on explanations of social mechanisms underlying the observed phenomena. This work is based on…
War-related Deaths in the 1992–1995 Armed Conflicts in Bosnia and Herzegovina: A Critique of Previous Estimates and Recent Results
Migration Decision-Making and Its Key Dimensions
Migration decisions are made in the context of personal needs and desires, and the individuals making these decisions face uncertain outcomes. Information about future opportunities is incomplete, and whether migration turns out to be a personal success or failure depends mostly on circumstances that are ex ante unknown and ex post not fully under the control of the individuals who migrate. This article elaborates on four dimensions of the comple…
Population and labour force projections for 27 European countries, 2002-052: Impact of international migration on population ageing
Population and labour force projections are made for 27 selected European countries for 2002-052, focussing on the impact of international migration on population and labour force dynamics. Starting from single scenarios for fertility, mortality and economic activity, three sets of assumptions are explored regarding migration flows, taking into account probable policy developments in Europe following the enlargement of the EU. In addition to age …
Bayesian demography 250 years after Bayes
Bayesian statistics offers an alternative to classical (frequentist) statistics. It is distinguished by its use of probability distributions to describe uncertain quantities, which leads to elegant solutions to many difficult statistical problems. Although Bayesian demography, like Bayesian statistics more generally, is around 250 years old, only recently has it begun to flourish. The aim of this paper is to review the achievements of Bayesian de…
Bayesian Population Forecasting: Extending the Lee-Carter Method
In this article, we develop a fully integrated and dynamic Bayesian approach to forecast populations by age and sex. The approach embeds the Lee-Carter type models for forecasting the age patterns, with associated measures of uncertainty, of fertility, mortality, immigration, and emigration within a cohort projection model. The methodology may be adapted to handle different data types and sources of information. To illustrate, we analyze time ser…
Replacement Migration Revisited: Simulations of the Effects of Selected Population and Labor Market Strategies for the Aging Europe, 2002–2052
A Framework for Estimating Migrant Stocks Using Digital Traces and Survey Data: An Application in the United Kingdom
An accurate estimation of international migration is hampered by a lack of timely and comprehensive data, and by the use of different definitions and measures of migration in different countries. In an effort to address this situation, we complement traditional data sources for the United Kingdom with social media data: our aim is to understand whether information from digital traces can help measure international migration. The Bayesian framewor…
Reforging the Wedding Ring: Exploring a Semi-Artificial Model of Population for the United Kingdom with Gaussian process emulators
We extend the "Wedding Ringâ agent-based model of marriage formation to include some empirical information on the natural population change for the United Kingdom together with behavioural explanations that drive the observed nuptiality trends
From Conflict Zones to Europe: Syrian and Afghan Refugees’ Journeys, Stories, and Strategies
This article explores the journeys of Syrian and Afghan refugees to Europe, looking at two of the largest and politically most salient flows of asylum seekers during the 2010s. Following political disturbances in their home countries, millions of Syrians and Afghans have been forcibly displaced or had to seek safety elsewhere. In search of protection for themselves and their families, some of them had to cross multiple borders to reach European d…
Assessing Timely Migration Trends Through Digital Traces: A Case Study of the UK Before Brexit
Digital trace data presents an opportunity for promptly monitoring shifts in migrant populations. This contribution aims to determine whether the number of European migrants in the United Kingdom (UK) declined between March 2019 and March 2020, using weekly estimates derived from the Facebook Advertising Platform. The collected data is disaggregated according to age, level of education, and country of origin. To examine the fluctuation in the num…
Forecasting Scottish Migration in the Context of the 2014 Constitutional Change Debate
Migration to and from Scotland might be affected by the outcome of the 2014 Scottish referendum on the constitutional future of the United Kingdom. This potential change in migration has not been thoroughly analysed to date. The aim of this paper is thus to present a set of predictions of the possible effects of Scottish independence on internal and international migration. In particular, different sources of uncertainty of future migration flows…
European migration governance in the context of uncertainty
Migration inherently embodies uncertainty and dynamism, eluding precise conceptualization, definition and measurement. Embedded within intricate migration driver environments and shaped by the diverse agency of actors involved—prospective migrants, intermediaries and policymakers—migration defies easy prediction and effective policy response. This inherent complexity within international migration flows poses immediate and long‐term governance ch…
Choosing the choice: Reflections on modelling decisions and behaviour in demographic agent-based models
This paper investigates the issues associated with choosing appropriate models of choice for demographic agent-based models. In particular, we discuss the importance of context, time preference, and dealing with uncertainty in decision modelling, as well as the heterogeneity between agents in their decision-making strategies. The paper concludes by advocating empirically driven, modular, and multi-model approaches to designing simulations of huma…
Quantifying paradigm change in demography
Demography is a uniquely empirical research area amongst the social sciences. We posit that the same principle of empiricism should be applied to studies of the population sciences as a discipline, contributing to greater self-awareness amongst its practit
Forecasting environmental migration to the United Kingdom: An exploration using Bayesian models
Integrating uncertainty in time series population forecasts: An illustration using a simple projection model
Population forecasts are widely used for public policy purposes. Methods to quantify the uncertainty in forecasts tend to ignore model uncertainty and to be based on a single model
Toward an Early Warning System for Monitoring Asylum-Related Migration Flows in Europe
Asylum-related migration is highly complex, uncertain, and volatile, which precludes using standard model-based predictions to inform policy and operational decisions. At the same time, asylum's potentially high societal impacts on receiving countries and the resource implications of asylum processes call for more proactive approaches for assessing current and future migration flows. In this article, we propose an alternative approach to asylum m…
Warriors Die Young: Increased Mortality in Early Adulthood of Scythians from Glinoe, Moldova, Fourth through Second Centuries bc
Scythians were nomadic groups, playing a dominant role on the Eurasian steppes in the Early Iron Age according to many archaeological and historical sources. In this paper, we aim at assessing demographic features and dynamics of a Scythian population from the Black Sea region. We hypothesise that they differed from other societies not only in terms of culture, but also demography: their fertility was lower, and life expectancy higher than in oth…
The science of choice: An Introduction
In October 2015, around 30 scholars convened at the Max Planck Institute for Demographic Research (MPIDR) in Rostock to discuss: (a) how individuals and families make decisions about marriage, chil
War-related Deaths in the 1992–1995 Armed Conflicts in Bosnia and Herzegovina: A Critique of Previous Estimates and Recent Results
Population and labour force projections for 27 European countries, 2002-052: Impact of international migration on population ageing
Population and labour force projections are made for 27 selected European countries for 2002-052, focussing on the impact of international migration on population and labour force dynamics. Starting from single scenarios for fertility, mortality and economic activity, three sets of assumptions are explored regarding migration flows, taking into account probable policy developments in Europe following the enlargement of the EU. In addition to age …
Replacement Migration Revisited: Simulations of the Effects of Selected Population and Labor Market Strategies for the Aging Europe, 2002–2052
When Demography Met Social Simulation: A Tale of Two Modelling Approaches
In this paper we present an agent-based model of a human population, designed to illustrate the potential synergies between demography and agent-based social simulation. In the modelling process, we take advantage of the perspectives of both disciplines: demography being more focused on matching statistical models to empirical data, and social simulation on explanations of social mechanisms underlying the observed phenomena. This work is based on…
Forecasting environmental migration to the United Kingdom: An exploration using Bayesian models
Probability and Social Science. Methodological Relationships between the Two Approaches
No abstract available
Integrating uncertainty in time series population forecasts: An illustration using a simple projection model
Population forecasts are widely used for public policy purposes. Methods to quantify the uncertainty in forecasts tend to ignore model uncertainty and to be based on a single model
Reforging the Wedding Ring: Exploring a Semi-Artificial Model of Population for the United Kingdom with Gaussian process emulators
We extend the "Wedding Ringâ agent-based model of marriage formation to include some empirical information on the natural population change for the United Kingdom together with behavioural explanations that drive the observed nuptiality trends
Forecasting Scottish Migration in the Context of the 2014 Constitutional Change Debate
Migration to and from Scotland might be affected by the outcome of the 2014 Scottish referendum on the constitutional future of the United Kingdom. This potential change in migration has not been thoroughly analysed to date. The aim of this paper is thus to present a set of predictions of the possible effects of Scottish independence on internal and international migration. In particular, different sources of uncertainty of future migration flows…
Quantifying paradigm change in demography
Demography is a uniquely empirical research area amongst the social sciences. We posit that the same principle of empiricism should be applied to studies of the population sciences as a discipline, contributing to greater self-awareness amongst its practit
Welfare participation: A comparison between immigrants and natives in the United Kingdom
European migration is a hotly debated topic in the United Kingdom. Using the Labour Force Survey data for 2012 this study analyses benefit claims among Central and Eastern European immigrants, immigrants from the old European Union member states and UK natives. Results of logistic regression modelling show that, compared to natives, social benefit claims are higher among immigrants from the eight Eastern European countries that became member stat…
Bayesian Population Forecasting: Extending the Lee-Carter Method
In this article, we develop a fully integrated and dynamic Bayesian approach to forecast populations by age and sex. The approach embeds the Lee-Carter type models for forecasting the age patterns, with associated measures of uncertainty, of fertility, mortality, immigration, and emigration within a cohort projection model. The methodology may be adapted to handle different data types and sources of information. To illustrate, we analyze time ser…
Bayesian demography 250 years after Bayes
Bayesian statistics offers an alternative to classical (frequentist) statistics. It is distinguished by its use of probability distributions to describe uncertain quantities, which leads to elegant solutions to many difficult statistical problems. Although Bayesian demography, like Bayesian statistics more generally, is around 250 years old, only recently has it begun to flourish. The aim of this paper is to review the achievements of Bayesian de…
Choosing the choice: Reflections on modelling decisions and behaviour in demographic agent-based models
This paper investigates the issues associated with choosing appropriate models of choice for demographic agent-based models. In particular, we discuss the importance of context, time preference, and dealing with uncertainty in decision modelling, as well as the heterogeneity between agents in their decision-making strategies. The paper concludes by advocating empirically driven, modular, and multi-model approaches to designing simulations of huma…
The science of choice: An Introduction
In October 2015, around 30 scholars convened at the Max Planck Institute for Demographic Research (MPIDR) in Rostock to discuss: (a) how individuals and families make decisions about marriage, chil
Warriors Die Young: Increased Mortality in Early Adulthood of Scythians from Glinoe, Moldova, Fourth through Second Centuries bc
Scythians were nomadic groups, playing a dominant role on the Eurasian steppes in the Early Iron Age according to many archaeological and historical sources. In this paper, we aim at assessing demographic features and dynamics of a Scythian population from the Black Sea region. We hypothesise that they differed from other societies not only in terms of culture, but also demography: their fertility was lower, and life expectancy higher than in oth…
Methodological Investigations in Agent-Based Modelling: With Applications for the Social Sciences
Agent-Based Modelling; ABM; Artificial Intelligence; AI; Computational social science; Social simulation; Population sciences
Streamlining Simulation Experiments with Agent-Based Models in Demography
In the last decade, the uptake of agent-based modeling in demography and other population sciences has been slowly increasing. Still, in such areas, where traditional data-driven, statistical approaches prevail, the hypothesis-driven design of agent-based models leads to questioning the validity of these models. Consequently, suitable means to increase the confidence into models and simulation results are required. To that end, explicit, replicab…
Model-Based Demography: Essays on Integrating Data, Technique and Theory
Book review of Model-Based Demography: Essays on Integrating Data, Technique and Theory. 2018. By THOMAS K. BURCH. Demographic Research Monographs Series. Cham: Springer. Pp. xviii+200. Open access (online) / £44.99 (hardcover). ISBN: 978-3-319-65433-1
A Framework for Estimating Migrant Stocks Using Digital Traces and Survey Data: An Application in the United Kingdom
An accurate estimation of international migration is hampered by a lack of timely and comprehensive data, and by the use of different definitions and measures of migration in different countries. In an effort to address this situation, we complement traditional data sources for the United Kingdom with social media data: our aim is to understand whether information from digital traces can help measure international migration. The Bayesian framewor…
Paleodemographic analysis of age at death for a population of Black Sea Scythians: An exploration by using Bayesian methods
OBJECTIVES: Studies of the demography of past populations involving deterministic life tables can be criticized for ignoring the errors of estimation. Bayesian methods offer an alternative, by focusing on the uncertainty of the estimates, although their results are often sensitive to the choice of prior distributions. The aim of this study is to explore a range of Bayesian methods for estimating age at death for a population of nomadic warriors-S…
Migration Decision-Making and Its Key Dimensions
Migration decisions are made in the context of personal needs and desires, and the individuals making these decisions face uncertain outcomes. Information about future opportunities is incomplete, and whether migration turns out to be a personal success or failure depends mostly on circumstances that are ex ante unknown and ex post not fully under the control of the individuals who migrate. This article elaborates on four dimensions of the comple…
From Conflict Zones to Europe: Syrian and Afghan Refugees’ Journeys, Stories, and Strategies
This article explores the journeys of Syrian and Afghan refugees to Europe, looking at two of the largest and politically most salient flows of asylum seekers during the 2010s. Following political disturbances in their home countries, millions of Syrians and Afghans have been forcibly displaced or had to seek safety elsewhere. In search of protection for themselves and their families, some of them had to cross multiple borders to reach European d…
Toward an Early Warning System for Monitoring Asylum-Related Migration Flows in Europe
Asylum-related migration is highly complex, uncertain, and volatile, which precludes using standard model-based predictions to inform policy and operational decisions. At the same time, asylum's potentially high societal impacts on receiving countries and the resource implications of asylum processes call for more proactive approaches for assessing current and future migration flows. In this article, we propose an alternative approach to asylum m…
From Uncertainty to Policy: A Guide to Migration Scenarios
This is an open access title available under the terms of a CC BY-NC-ND 4.0 License. It is free to read, download and share on Elgaronline.com. This unique book provides a practical and interdisciplinary blueprint for determining quantitative scenarios of future international migration. Focusing on complexity and uncertainty as the defining challenges of migration, it explores how scenario building can be used to inform and underpin effective mig…
Sociology (19 works) · Computer Science (17 works) · Economics (15 works) · Geography (14 works) · Population (14 works) · Demography (12 works) · Insurance, Mortality, Demography, Risk Management (12 works) · Migration and Labor Dynamics (10 works) · Political science (9 works) · Artificial Intelligence (8 works)