Eric Silverman

University of Glasgow | UofG · MRC/CSO Social and Public Health Sciences Unit

In a recent paper Zhang et al. elegantly incorporate the evolution of inter-host virus fitness into an epidemiological model. They show that this leads to substantial changes in the system dynamics and in particular that evolution can ``rescue" the pathogen population if the mutation rate is high enough. However, their model rests on the assumption...

To help health economic modelers respond to demands for greater use of complex systems models in public health. To propose identifiable features of such models and support researchers to plan public health modeling projects using these models. A working group of experts in complex systems modeling and economic evaluation was brought together to dev...

Background Agent based models are a computational methodology in which systems of simulated heterogeneous agents interact with one another and their environment; they are a research tool with the potential to provide greater understanding of the complex, interdependent, and systemic determinants of population health challenges, particularly when co...

Since the beginning of the COVID-19 pandemic, various models of virus spread have been proposed. While most of these models focused on the replication of the interaction processes through which the virus is passed on from infected agents to susceptible ones, less effort has been devoted to the process through which agents modify their behaviour as...

Social care is a frequent topic in UK policy debates, with widespread concern that the country will be unable to face the challenges posed by the increase in demand for social care. While this is a societal problem whose dynamics depends on long-term trends, such as the increase of human lifespans and the drop of birth-rates, a short-term crisis, s...

Human groups show a variety of leadership dynamics ranging from egalitarian groups with no leader, to groups with changing leaders, to absolutist groups with a single long-term leader. Here, we model transitions between these different phases of leadership dynamics, investigating the role of inequalities in relationships between individuals. Our re...

In this proof-of-concept work, we evaluate the performance of multiple machine-learning methods as surrogate models for use in the analysis of agent-based models (ABMs). Analysing agent-based modelling outputs can be challenging, as the relationships between input parameters can be non-linear or even chaotic even in relatively simple models, and ea...

The Covid-19 pandemic is deeply affecting every aspect of people daily lives around the world, both through the effects of the virus itself and the related mitigation measures put into place by governments. However, the impact of the virus is not equal within each society, as an increasing number of empirical studies show that its effects at the in...

Today’s most troublesome population health challenges are often driven by social and environmental determinants, which are difficult to model using traditional epidemiological methods. We agree with those who have argued for the wider adoption of agent-based modelling (ABM) in taking on these challenges. However, while ABM has been used occasionall...

Providing for the needs of the vulnerable is a critical component of social and health policy-making. In particular, caring for children and for vulnerable older people is vital to the wellbeing of millions of families throughout the world. In most developed countries, this care is provided through both formal and informal means, and is therefore g...

In this paper, we evaluate the performance of multiple machine-learning methods in the emulation of agent-based models (ABMs). ABMs are a popular methodology for modelling complex systems composed of multiple interacting processes. The analysis of ABM outputs is often not straightforward, as the relationships between input parameters can be non-lin...

Providing for the needs of the vulnerable is a critical component of social and health policy-making. In particular, caring for children and for vulnerable older people is vital to the wellbeing of millions of families throughout the world. In most developed countries, this care is provided through both formal and informal means, and is therefore g...

Today's most troublesome population health challenges are often driven by social and environmental determinants, which are difficult to model using traditional epidemiological methods. We agree with those who have argued for the wider adoption of agent-based modelling (ABM) in taking on these challenges. However, while ABM has been used occasionall...

Human groups show a variety of leadership structures from no leader, to changing leaders, to a single long-term leader. When a leader is deposed, the presence of a power vacuum can mean they are often quickly replaced. We lack an explanation of how such phenomena can emerge from simple rules of interraction between individuals. Here, we model trans...

Current demographic trends in the UK include a fast-growing elderly population and dropping birth rates, and demand for social care among the aged is rising. The UK depends on informal social care-family members or friends providing care-for some 50% of care provision. However, lower birth rates and a greying population mean that care availability...

Current demographic trends in the UK include a fast-growing elderly population and dropping birth rates, and demand for social care amongst the aged is rising. The UK depends on informal social care -- family members or friends providing care -- for some 50\% of care provision. However, lower birth rates and a graying population mean that care avai...

Recently we have witnessed a number of rapid shifts toward populism in the rhetoric and policies of major political parties, as exemplified in the 2016 Brexit Referendum, 2016 US Election, and 2017 UK General Election. Our perspective here is to focus on understanding the underlying societal processes behind these recent political shifts. We use no...

Botometer distributions. The distributions of scores assigned by Botometer to samples of 2,000 accounts taken from each of the three focal groups. (PNG)

All groups in the sample. Plot showing the groups found by our sample and summarising the how the accounts follow one antoher at a group level. Groups shown (> 200 members) are sized by the number of members. Lines between groups are the same colour as the originating group. Links are the same colour as the group containing the following accounts a...

Group dynamics. Movie showing the dynamics of the three groups and their following behaviour over time. It shows how initial growth and internal following behaviour of the GOP group is superceded by growth and following of the Trump group. Areas of groups represent the size of the group at the time shown. For each month, link widths are scaled to r...

Despite tremendous advancements in population health in recent history, human society currently faces significant challenges from wicked health problems. These are problems where the causal mechanisms at play are obscured and difficult to address, and consequently they have defied efforts to develop effective interventions and policy solutions usin...

A model-based demography is a new approach to better understand human populations. It investigate the interactions between various population systems, as well as the functional mechanisms behind them. The interactions and mechanisms are best described by formal models based on data and theory-based rules, derived from observations of system propert...

In this chapter we will examine one influential modelling project in detail: the residential segregation model by Schelling. This model has been a seminal example of abstract social modelling since its inception; our analysis will discuss the development of the model itself as well as its subsequent effect on the field and on modelling more general...

Modern demography, while growing increasingly interdisciplinary over years, has largely remained a data-focused discipline. Demographic research often proceeds under the premises of logical empiricism, in which data is the primary focus on theoretical development or innovation receive far less emphasis. In this chapter, we will investigate some dem...

In this chapter, we investigate the use of simulation in Artificial Life as a means for ‘making the artificial real’ – and in doing so develop a framework for artificiality in computational models of living systems. I first describe the differences in the Strong and Weak Artificial Life perspectives, and how each of these attempts to justify itself...

In this chapter we examine an agent-based model of social care costs in the context of an ageing population. The model brings together statistical demographic modelling with a spatial agent-based model including a rudimentary economic model. Agents undergo the core demographic processes of fertility, mortality, and migration, and as they age they m...

Having discussed the current state-of-the-art in modelling for the social sciences, we will begin to delve more deeply into the modelling frameworks discussed thus far. Both Alife and social science simulation will be studied using these modelling frameworks, which will allow us to examine the limitations of these approaches to modelling. We will t...

In Part I, our analysis of modelling focused primarily on the field of artificial life and population biology. In Part II, we will begin to investigate the application of agent-based modelling to the social sciences. This chapter will describe the current status of agent-based social science research, outlining some of the most influential work in...

This chapter takes our previous discussion of simulation in Artificial Life and places it into the broader context of population biology, which can be viewed as an earlier progenitor of Alife. Population biologists frequently use mathematical models to investigate the behaviour of animal populations, drawing from a similar methodological toolbox as...

This chapter examines the philosophical underpinnings of simulation science, with particular emphasis on the new challenges created by the increased use of computational modelling throughout many disciplines of science. In order to illuminate these philosophical discussions, the discussion here focuses on simulation in the context of Artificial Lif...

This open access book examines the methodological complications of using complexity science concepts within the social science domain. The opening chapters take the reader on a tour through the development of simulation methodologies in the fields of artificial life and population biology, then demonstrates the growing popularity and relevance of t...

In this chapter we will go further and propose that ABMs, beyond just herald- ing the birth of a new subfield, have the potential to push the demographic 1 research agenda in a new direction. We will summarise the historical development of demography from Graunt’s time until the present day, and demonstrate the demography has displayed a penchant fo...

This open access book examines the methodological complications of using complexity science concepts within the social science domain. The opening chapters take the reader on a tour through the development of simulation methodologies in the fields of artificial life and population biology, then demonstrates the growing popularity and relevance of t...

General presentation of a volume which will appear in the Springer Methodos Series, edited by Daniel Courgeau and Robert Franck, on agent-based modelling.

This chapter aims to contribute to the debate on the role of model-based approaches, such as agent-based modelling, in the future of demography. First we call attention to the developments of the discipline since the 17th century, and we describe its four successive paradigms related to the period, cohort, event-history and multilevel perspectives....

This paper presents an agent-based model of fixed-term academic employment in a competitive research funding environment. The goal of the model is to investigate the effects of job insecurity on research productivity. Agents may be either established academics who may apply for grants, or postdoctoral researchers who are unable to apply for grants...

In this paper, we examine the four Idols – errors of thinking and judgement – which according to Francis Bacon’s Novum Organum (1620) beset human minds. These are Idols of the Tribe – false assertions that the sense of man is the measure of things; Idols of the Cave – idols of the individual man; Idols of the Market Place – formed by the intercours...

Here we posit that ABMs can be classed as one manifestation of a broader paradigm, system-based modelling, which is focused primarily on understanding interactions. In our view, this paradigm can form the foundation of the next step in the cumulative progression of demographic knowledge. This paper proceeds first by detailing the successive paradi...

Previous work has proposed that computational modelling of social systems is composed of two primary streams of research: systems sociology, which is focused on the generation of social theory; and social simulation, which focuses on the study of real-world social systems. Here we argue that the social simulation stream stands to benefit from recen...

BACKGROUND 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 practitioners. OBJECTIVE The paper aims to include measurable data in the study of changes...

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 simu...

Background: We extend the "Wedding Ring‟ 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. Objective: We propose a method to explore statistical properties of agent-based demographic...

In this paper we present an agent-based model of the ageing UK population. The goal of this model is to integrate statistical demographic projections of the UK population with an agent-based platform that allows us to examine the interaction between population change and the cost of social care in an ageing population. The model captures the basic...

In this paper we present an agent-based model of the dynam-ics of mortality, fertility, and partnership formation in a closed popula-tion. One of our goals is to bridge the methodological and conceptual gaps that remain between demography and agent-based social simulation ap-proaches. Model construction incorporates elements of both perspectives, w...

The UK's population is ageing, which presents a challenge as older people are the primary users of health and social care services. We present an agent-based model of the basic demographic processes that impinge on the supply of, and demand for, social care: namely mortality, fertility, health-status transitions, internal migration, and the formati...

This paper introduces a major new cross-disciplinary research project that looks at the UK health and social care system, as part of an ambitious, broader initiative to apply methods from complexity science to a range of key global challenges. This particular project aims to develop new, integrated models for the supply and demand of both health an...

Since its inception, ALife has moved from producing large numbers of highly-idealised, theoretical models towards greater integration with empirically collected data. In contrast, demography — the interdisciplinary study of human populations — has been largely following the principles of logical empiricism, with models driven mainly by data, and in...

Quinn (2001) sought to demonstrate that communication between simulated agents could be evolved without pre-defined communication channels. Quinn’s work was exciting because it showed the potential for ALife models to look at the real origin of communication; however, the work has never been replicated. In order to test the generality of Quinn’s re...

Finding robust explanations of behaviours in Alife and related fields is made difficult by the lack of any formalised definition of robustness. A concerted effort to develop a framework which allows for robust explanations of those behaviours to be developed is needed, as well as a discussion of what constitutes a potentially useful definition for...

Quinn (2001) sought to demonstrate that communication be-tween simulated agents could be evolved without pre-defined communication channels. Quinn's work was exciting because it showed the potential for ALife models to look at the real origin of communication; however, the work has never been replicated. In order to test the generality of Quinn's r...

Thought displays a systematicity that cannot be explained by the connections between simple neuron-like units. This is the gist of Fodor and Pylyshyn’s (F & P) challenge to connectionism. Furthermore, they assume thought to be representational and there is no available method to detect representations among the mere relations between neurons and th...

Robustness is a property present in every living system which provides resilience against internal or external perturbations. Robustness is also highly desirable in engineered systems, as it makes them more resistant to unpredicted events. Despite its ubiquity, this concept is not yet understood and no existing framework provides a methodology to q...

For practitioners across a growing number of academic disciplines there is a strong sense that simulation models of complex realworld systems provide something that differs fundamentally from that which is offered by mathematical models of the same phenomena. The precise nature of this difference has been difficult to isolate and explain, but, occa...

We identify two distinct themes in social science modelling. One, more specific, approach is that of social simulation which addresses how behaviour of many actors can lead to emergent effects. We argue that this approach, while useful as a tool in social science policy devel- opment, is fundamentally constrained due to the fact that its models are...

Proceedings from the ninth International Conference on Artificial Life; papers by scientists of many disciplines focusing on the principles of organization and applications of complex, life-like systems. Artificial Life is an interdisciplinary effort to investigate the fundamental properties of living systems through the simulation and synthesis of...

Strong articial life research is often thought to rely on Alife systems as sources of novel empirical data. It is hoped that by augmenting our observations of natural life, this novel data can help settle empirical questions, and thereby separate fun- damental properties of living systems from those aspects that are merely contingent on the idiosyn...

For practitioners across a growing number of academic disciplines there is a strong sense that simulation models of complex realworld systems provide something that differs fundamentally from that which is offered by mathematical models of the same phenomena. The precise nature of this difference has been difficult to isolate and explain, but, occa...