Revisiting aspiration and ability in international migration

ABSTRACT

It is a refreshingly simple thought that migration is the combined result of two factors: the aspiration to migrate and the ability to migrate. Without having to resort to overly structural or individualistic explanations, this analytical distinction helps disentangle complex questions around why some people migrate but others do not. Still, aspiration and ability raise their own thorny theoretical and methodological questions. To begin with, what does it mean to have migration aspirations? How can such concepts be objects of empirical research? And is it meaningful to say that individuals possess the ability to migrate if their preference is to stay? The aspiration/ability model was originally proposed in this journal and has since been diversely applied and adapted. In this article, we look back at more than a decade of research to examine a series of theoretical and empirical developments related to the aspiration/ability model and its extensions. We identify two-step approaches as a class of analytical frameworks that share the basic logic of the aspiration/ability model. Covering expansive theoretical, methodological and empirical ground, we seek to lay a foundation for new research on global migration in its diverse forms.

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KEYWORDS:

• Migration aspirations
• aspiration/ability model
• capabilities
• two-step approaches
• migration theory

Introduction

Under what conditions do people decide to move? That has been the key question in migration theory, with the assumption being that if people so decide, they move. But such a model seems untenable in a world where prospective migrants face overwhelming obstacles in the form of legal hurdles, exorbitant costs or dangerous journeys. Actual migration requires more than a positive assessment of its costs and benefits. Many migration desires remain unfulfilled, but nevertheless have consequences for individuals and communities.

The conceptual pair of aspiration and ability was introduced in this very journal by Carling (2002) to explain the prevalence of what he termed ‘involuntary immobility’ – the aspiration to migrate but the inability to do so – among people in Cape Verde. This analytical framework has resonated with the work of other migration researchers who have taken issue with sweeping accounts of mobility and focused on what Vigh (2009, 93) has called ‘the restricted character of social and global mobility’ (e.g. Alpes 2012; Burrell 2012; Gaibazzi 2014; Jónsson 2008; Paul 2011). Beyond highlighting the frustrations of restricted mobility, the distinction between wishing to migrate and being able to do so has inspired more general analyses of migration processes (de Haas 2010; Docquier, Peri, and Ruyssen 2014). In this article, we revisit the potential of the aspiration/ability model (Carling 2002) and its offshoots in migration theory. The model was presented as a general framework, appropriate ‘for analysing migration within most contexts’ (Carling 2002, 8). Here we address diverse aspects of the model’s applicability and limitations. We look back on more than a decade of research to examine areas of progress and of continuing challenge. We start by relating the aspiration/ability model to a broader set of approaches to migration theory. In 10 sections we then examine methodological, empirical and theoretical developments in the study of migration aspiration, migration ability and interaction between the two.

Our objective is neither to endorse a preservation of the aspiration/ability model in its original form nor to promote a particular revision of it. Instead, we use the model as a starting point for consolidating diverse strands of research that disaggregate migration dynamics along similar lines. The next section accounts for this common feature, which we refer to as a two-step approach.

Before proceeding, we briefly review the original model and its constituent elements (Figure 1). In this model, a migration ‘aspiration’ is defined simply as a conviction that migration is preferable to non-migration; it can vary in degree and in the balance between choice and coercion. The fluid boundary of migration aspirations is represented by a dashed line in the figure. Among those who aspire to migrate, some have the ability to do so, manifest in their actual, observable migration. Those who do not migrate fall into two categories: involuntary non-migrants, who have aspirations to migrate but lack the ability, and voluntary non-migrants, who stay because of a belief that non-migration is preferable to migration.

Figure 1. The aspiration/ability model. Reproduced from Carling (2002).

Each of the two decisive factors – aspiration and ability – is determined simultaneously from above and below. The aspiration to migrate emerges within a particular macro-level emigration environment, encompassing the social, economic and political context in which particular social constructions of migration exist. Individual characteristics interact with this environment to determine patterns of who wishes to leave and who wishes to stay.

In a similar vein, the ability to migrate is conditioned by the macro-level context of obstacles and opportunities, referred to in the model as the immigration interface. The interface comprises a range of possible modes of migrating, either in compliance with or defiance of the various migration regulations, such as legal labour migration, family reunification, asylum migration and visa overstaying. Each mode is associated with a different set of barriers and requirements, reflected in person-to-person variation in the ability to migrate.

Taking a two-step approach

The aspiration/ability model centres on the break-up of migration into two separate steps: the evaluation of migration as a potential course of action and the realisation of actual mobility or immobility at a given moment. Looking at the past decade’s diverse migration research, we can identify such a two-step approach as a broad class of analytical frameworks. Many studies do not use the vocabulary of aspiration and ability, nor do they form a cross-referenced body of literature. Still, the underlying logic is distinct.

Two-step approaches are united by their attention to thoughts and feelings that precede migration outcomes. These psychological elements have been variously described as migration aspirations, desires, wishes, intentions or needs (Alpes 2014; Bal and Willems 2014; Black and Collyer 2014; Cai et al. 2014; Carling and Collins 2018; Czaika and Vothknecht 2014; De Jong, Richter, and Isarabhakdi 1996). There are substantive nuances between some of these terms, which we consider in the following section. But for the fundamental logic of the theoretical model, our preferred term migration ‘aspirations’ is interchangeable with migration ‘wishes’ or ‘desires’.

Two-step approaches share the premise that migration aspirations may or may not result in actual mobility. Variation in migration across time or between groups can be attributed to differences in aspiration, ability or both. And when there is no observable variation, there might be differences in aspiration and ability that cancel each other out. As an example, consider the international migration rates from urban and rural areas in Mexico. Compared to urban dwellers, rural residents are more likely to want to migrate but less likely to realise these desires if they have them (Creighton 2013). If we try to explain rural–urban differences on the basis of observed outcomes alone, we are muddling the two underlying processes.

Various renditions of two-step approaches have been applied in disparate areas of the migration research landscape. The notion of two steps is most explicit in quantitative studies that employ data on both aspirations and behaviour. A number of such studies have addressed residential mobility in high-income countries (e.g. Coulter 2013; de Groot et al. 2011). In the realm of international migration, Docquier and his economist colleagues (2014) recently combined country-level survey data on migration desires with estimates of net migration flows to model what they refer to as ‘the determinants of potential and actual migration’. Their two-step framework of migration draws from labour market economics, with the analogy of people entering a pool of jobseekers first and finding employment opportunities second. In the context of humanitarian crises, geographers Black and Collyer (2014) use the metaphor of being ‘trapped’ to describe populations who are in need of escaping danger but are unable to do so. Across various disciplines and areas of application, two-step approaches not only help explain migration patterns, but also yield insights into the absence of migration: immobility could result from a preference to stay or an inability to fulfil migration desires.

Measuring migration aspirations

Two-step approaches hinge on identifying migration aspirations, which are inherently elusive. Many researchers have sought to do so through surveys, but how can survey questions properly determine whether or not people wish to migrate? The various survey instruments reflect methodological challenges and raise theoretical questions about what exactly it is we are trying to measure.

Survey questions enquiring into the possibility of migrating to another country take seven main forms, as laid out in Table 1. The diversity of forms lies not only in wording variation; the questions differ fundamentally. The first type of question, which directly addresses migration aspirations or desires, indexes a general evaluation of whether or not migrating would be better than staying. Its core concept is ‘pure’ preference, disregarding any possible constraints on carrying through. The pertinent question in the Gallup World Poll (GWP) begins with ‘Ideally, if you had the opportunity … ’, which is the notion captured by our use of the word ‘aspiration’: a wish, desire or preference to migrate.

Table 1. A typology of survey questions on migration aspirations and related concepts.

Theoretical concept	Selected survey questions
1. Aspiration, desire or preference to migrate	‘Ideally, if you had the opportunity, would you like to move permanently to another country, or would you prefer to continue living in this country?’ (OECD 2015); ‘Ideally, if you had the opportunity, would you like to go abroad to live or work some time during the next five years, or would you prefer staying in [this country]?’ (Carling 2013); ‘Would you like to someday live in the United States?’ (Becerra et al. 2010); ‘Would you like to move from your current location to a different place at some point in the next 10 years?’ (Young Lives 2013)
2. Intentions or plans to migrate	‘Do you intend to migrate abroad?’ (van Dalen, Groenewold, and Schoorl 2005); ‘Are you planning to move to [preferred destination country] in the next 12 months, or not?’ (Gallup 2008); ‘Will you try to go to [preferred destination country] within the next five years?’ (Carling 2013)
3. Preparations for emigration	‘Have you done any preparation for this move (for example, applied for residency or visa, purchased the ticket, etc.)?’ ‘During the past five years, have you obtained a visa for going to Europe? Have you applied for one during the past five years?’ (Ersanilli, Carling, and de Haas 2011)
4. Consideration of migration	‘Have you and your family seriously considered moving to another country?’ (Wood et al. 2010); ‘Are you thinking about looking for work abroad after finishing your studies?’ (Kureková 2014); ‘Have you thought about moving in the future, outside the locality/community where you currently live?’ (Creighton 2013)
5. Conditional willingness to migrate	‘If someone were to give you the necessary papers for going to live or work in Europe, what would you do? Would you stay here or go to Europe?’ (Carling 2013); ‘If you could improve your work or living conditions, how willing or unwilling would you be to move outside your country?’ (Drinkwater 2002)
6. Necessity of migration	‘Do you think you will have to migrate to the United States?’ (Becerra et al. 2010); ‘I feel that I’m going to have to migrate to the U.S. when I graduate in order to find a job to support myself or my family’ (Becerra 2012)
7. Likelihood of migration	‘How likely do you think it is that you will live elsewhere in the future?’ (Bjarnason and Thorlindsson 2006); ‘Do you expect to be living in this city in two years?’ (Madhavan and Landau 2011); ‘In the next 12 months, are you likely or unlikely to move away from the city or area where you live?’ (Dustmann and Okatenko 2014)

Notes: References are primarily to publications that present results based on each question. Dustmann and Okatenko (2014) and OECD (2015) use data from the GWP. Carling (2013) and Ersanilli, Carling, and de Haas (2011) are publications from the EUMAGINE project.

The second type of question addresses intentions or plans, endeavouring to narrow the gap between preferences and behaviour. Some surveys first ask about preferences and then follow with queries about intentions and plans (Carling 2013; OECD 2015). The third type of question goes even further towards the realisation of migration and asks about preparations, such as obtaining a passport or applying for a visa. These three question types thus form a continuum of concreteness, generally correlated with a sharp decline in prevalence. For instance, the GWP found that 32% of respondents in sub-Saharan Africa had a desire to emigrate, 4% planned to do so within the next year and 1% were making relevant preparations (OECD 2015).

The fourth type of question examines whether or not people have considered migration at all. Like the questions about preparations, this type enquires about empirical facts. All six other types address preferences and assessments that have no ‘true’ answer and could change in either direction from one day to the next.

The fifth type of question presents respondents with a hypothetical scenario. When the EUMAGINE project asked whether respondents would migrate to Europe if they were given the necessary papers, many who did not express a preference for migration nevertheless answered the question affirmatively (Carling et al. 2013). This seems counterintuitive, but makes sense in societies where migration is a scarce yet coveted opportunity.

The sixth type of question addresses respondents’ perceived necessity to migrate. It is an uncommon approach, which implicitly assumes that people migrate because they have to and not because they want to. In their version of a two-step analysis of migration in humanitarian crises, Black and Collyer (2014) also referred to mobility needs rather than desires, although without considering implications for survey questions.

The final type of question enquires about the likelihood of migration and differs from all the others in two ways. First, it takes a bird’s-eye view on the respondent’s future. Second, it collapses the entire two-step approach by asking about an outcome that will depend on both aspiration and ability.

The questions vary not only with respect to theoretical concept (aspiration, intention, likelihood, etc.), but also in terms of how the action itself is described. Some refer to ‘migrating’, but others to ‘moving’ or ‘living elsewhere’. The choice of words may bias a response, for example, when ‘migration’ has particular, culturally specific connotations. EUMAGINE avoided using ‘migration’ in questions and referred instead to ‘living or working abroad’.

We see three challenges arising from attempts to capture migration aspirations using survey methodology. The first is the conceptual vagueness surrounding the object of evaluation, which we return to later in this article. Earlier migration research more explicitly tried to disentangle the relationship between concepts – such as intentions, expectations, social norms and residential satisfaction – and their influence on migration behaviour. These efforts could be observed particularly through the elaboration of decision-making models that treated each as distinct determinants of migration preferences (De Jong 2000; De Jong et al. 1983; Fawcett 1985 ; Gardner et al. 1985 ). However, today’s migration scholars have generally not picked up where their predecessors left off.

A second challenge, common to much survey research, lies in trying to capture complex phenomenon through posing simple questions. For good reasons, most of the examples in Table 1 are yes/no questions. Yet, migration aspirations can be understood as a continuum, in which only people at or near the extremes – with firmly established convictions to leave or to stay – give predictable answers. A large segment in the middle gives answers that heavily depend on the context and the formulation of the question (Carling 2014). An apparent solution would be to use Likert scales, which differentiate between strengths of attitudes. But such scales introduce new problems, especially in cross-cultural settings. A better approach is to include a series of questions that together elicit descriptions of different strengths and dimensions of migration aspirations.

The third challenge is perhaps the trickiest: capturing the potentially transient nature of aspirations. A few panel studies have examined changes over time (Coulter 2013), and Gallup has published select time series from the GWP. But in most cases, surveys are one-off data collection exercises. This constraint can be loosened by including questions about past considerations of migration and about hypothetical responses to migration opportunities (cf. Table 1).

Mapping migration aspirations

Surveys with questions about migration aspirations have produced extensive empirical data. Where Carling (2002) made the informed guess that migration aspirations and involuntary immobility were widespread, we are now in a position to assemble quantitative estimates. The GWP is unique in its near-global coverage and consistent methodology. Although its data have not contributed much to understanding the dynamics of migration aspirations since very few scholars have been granted access to the microdata, the published aggregate data can be mined for analytical insights.

Figure 2 maps the global prevalence of migration aspirations based on responses to the GWP question ‘Ideally, if you had the opportunity, would you like to move permanently to another country, or would you prefer to continue living in this country?’ The proportion of positive responses reaches its highest levels in Sierra Leone (56%), Liberia (54%), Haiti (52%) and the Dominican Republic (52%). Questions about migration intentions and preparations produce very different levels and other country rankings though preserve the same overall picture of regional differences: migration aspirations are particularly high in West and Central Africa, Central America and the Caribbean. They also tend to be higher in small countries.

Figure 2. Migration aspirations illustrated by the proportion of GWP respondents who would prefer to move permanently to another country. Based on data reported in OECD (2015) for the period 2007–2013. For exact question, see Table 1.

Beyond geographical differences, a key point of interest is the global prevalence of migration aspirations. The GWP estimated that 14% of the world’s adult population around 2010 aspired to migrate, which is much higher than the proportion of actual migrants, about 4% (OECD 2015). Such statistics support the argument that we live in an ‘age of involuntary immobility’ rather than an ‘age of migration’ (cf. Carling 2002). But, we must ask, are the people who respond affirmatively to the GWP question truly involuntarily immobile?

The GWP question has two shortcomings. First, responses to the counterfactual ‘Ideally, if you had the opportunity … ’ are exceedingly hard to interpret. We do not know what distinguishes the ‘ideal’ situation from respondents’ actual circumstances. Differences in how people interpret the conditional framing of the question might overshadow differences in attitude towards migration. Second, the GWP underestimates migration aspirations by restricting the question to moving ‘permanently’. A large share of migrants initially intend to return, though many indefinitely postpone their return and thus become permanent migrants. If respondents take the GWP question literally, the results exclude aspirations for circular or eventually return migration. Yet, this restriction would often make little sense. For instance, consider Syrian refugees in the Middle East, who may or may not prefer to go to Europe rather than remain in the region. The GWP question would single out those who want to settle permanently in Europe, while those who want leave but have a hope of one day returning would be collapsed with respondents who did not want to leave at all.

These challenges do not discredit the GWP data, though they underscore the need for differentiated analyses. Table 2 illustrates the effect of GWP’s reference to permanent migration by comparing results with those of EUMAGINE. This survey included a question that resembles GWP’s but refers to ‘living and working abroad’ with the implicit possibility of returning. While the GWP uses nationally representative samples, the EUMAGINE team selected four research areas within each country, deliberately representing a diversity of contexts. Figures in Table 2 show the range of estimates for the four localities.

Table 2. Comparative display of survey results about migration aspirations.

	GWP (2007–2013) ‘Move permanently to another country’		EUMAGINE (2011) ‘Go abroad to live or work some time during the next five years’
	Age 15+	Age 15–24	Age 18–39	Age 18–24
Senegal	37	51	57–84	69–87
Morocco	29	45	48–66	57–71
Ukraine	21	37	40–54	41–61
Turkey	11	16	37–42	43–55

Source: OECD (2015) for GWP data; original data from the EUMAGINE survey.

Two points stand out. First, the ordering of the four countries with respect to migration aspirations is the same in both surveys (based on the comparable below-25 age groups and the median of the EUMAGINE data range). This suggests that there are relatively stable cross-national differences in the prevalence of migration aspirations. Second, the figures from the EUMAGINE survey are consistently higher than those from the GWP. A likely explanation for this consistency is the different wording of the question.

EUMAGINE data uncover a caveat regarding country-level data: differences in migration aspiration can be greater between regions within a country than between countries. Analyses of the EUMAGINE data show that the effect of localities on migration aspirations remains large after controlling for socioeconomic characteristics (Carling, Ersanilli, and de Haas 2012). A more meaningful map of migration aspirations would thus be more fine-grained than the one here (Figure 2). It would reveal regions of high emigration desires in Brazil, China and India, for instance, which are obscured by national averages.

Contextualising migration aspirations

Survey questions about migration aspirations are meant to reveal variation that we can interpret, yet the comparability of the data is something that must be called into question. To illustrate, when we read the GWP results that desires to emigrate are higher in the United Kingdom (29%) than Afghanistan (21%), our conventional view on migration pressures is challenged. But the survey’s follow-up questions then reveal important differences: the proportion of people making preparations for emigration is three times higher in Afghanistan than in the United Kingdom. We see, therefore, how multiple survey questions can add depth to cross-national comparisons and sociocultural environments can shape people’s thoughts about migration in more subtle ways.

The context of migration aspirations includes social norms and expectations about migrating or staying, opportunities for migration and the more general structural forces facilitating or constraining particular migration trajectories. The environment not only affects the level of migration aspirations, but also their inherent meaning. Answers to survey questions reflect the interplay between question formulation and context-specific meanings. For instance, Mondain and Diagne (2013, 512) claim that in Senegal, migration is ‘an almost obligatory rite of passage among young men’. A survey question on migration aspirations is likely to capture a desire that exists in that respondent’s imagination before the question is posed. In the United Kingdom, by contrast, the high level of positive responses may reflect a non-committal, context-dependent evaluation more than a pre-existing life ambition. Yet, a young Brit who is actually preparing for migration may be making a more radical choice than a Senegalese guy who is following the ‘near-obligatory’ social blueprint.

Ethnographic studies have explored and theorised a variety of culturally specific thoughts and feelings about migration. Pajo (2008) emphasises the geographical rootedness of migration aspirations in detailing how Albanians in Greece see onward migration as a form of ‘fulfilment’ that is territorialised as the property of other countries. Mains (2011), in his research among Ethiopian youth, theoretically connects migration aspirations with experiential temporalities. His informants experienced unemployment as a problem of how time unfolds in Ethiopia, and saw migration as a way of re-entering linear processes of progress through time. The possibility of migration thus held the promise of a spatial fix to a temporal problem. Horst (2006) describes how intense resettlement desires among Somali refugees in Kenya were pathologised and interpreted as a form of spirit possession. In urban Côte d’Ivoire, Newell (2012) examined migration as a form of consumption, offering a novel approach to understanding how migration is evaluated and desired.

These four samples from the rich ethnographic literature on migration exemplify how concepts such as place, time, health and consumption can unpack emic understandings of migration aspirations and yield connections with unexpected bodies of theory. The focus in each case, however, has been on understanding the context-specific social dynamics, not on developing general theory.

Theorising migration aspirations

So what is actually captured when we speak about migration aspirations? What psychological processes are at work? And how are they socially conditioned? Within the migration literature, epistemological discussion about such issues is generally weak. But a potential for connecting with the broader psychological and social-science literature exists, as some migration scholars have shown with reference to capacity to aspire (Czaika and Vothknecht 2014), desire as a social force (Collins 2018), geographical imaginaries (Andrucki 2013), preference formation theory (Coulter, van Ham, and Feijten 2011), the Rubicon model (Kley 2011) and theory of planned behaviour (De Jong 2000).

Such frameworks cater to diverse epistemologies and theoretical interests. Discussing the merits of each is beyond the scope of this article, but they nonetheless highlight shared issues concerning how generic frameworks can be applied to the first step of what we have called two-step approaches to understanding migration. These issues can be illustrated through, for example, seeing migration aspirations as a form of attitude (Carling 2014). An attitude has been defined as ‘a psychological tendency that is expressed by evaluating a particular entity with some degree of favour or disfavour’ (Eagly and Chaiken 1993, 1). This definition is useful in the context of migration aspirations. ‘Tendency’ suggests balance between stability and volatility that resonates with what we know about migration aspirations; ‘expressed’ emphasises a communicative aspect. But the crucial point – which is common to the application of other conceptual frameworks – is the nature of the ‘entity’ being evaluated.

Here we see several possible conceptualisations, which intersect with each other. First, we can understand migration aspirations as a comparison of places. The value of living in a specific place depends on the characteristics of that place, modified by the individual’s needs and preferences. This is the basic logic of push–pull models, connecting migration aspirations to concepts such as place utility, spatial preferences and geographical imaginaries. Potential destinations are an important part of the emigration environment, though they are present through the locally existing ideas and meanings attached to these places. This is true not only of specific locations elsewhere, but also of the more elusive deictic places such as ‘here’, ‘there’ and ‘abroad’.

The second possible approach is to see migration aspirations as a comparison of culturally defined projects. People’s notion of migration will often be based on a ‘migration project’, a socially constructed entity that embodies particular expectations. For instance, Lubkemann (2005) refers to an idealised ‘emigrant script’ and, as already noted, Mondain and Diagne (2013), like many others, have examined migration as a ‘rite of passage’. In situations of conflict or repression, the classical trio of exit, voice and loyalty (Hirschman 1970) can be interpreted as three alternative projects – the first of which implies migration. When the importance of culturally defined projects is acknowledged, interpreting migration aspirations as the preference of one place over another seems a banal rendering of the processes at work. But the projects are nevertheless produced by the differentiated meanings attached to places.

A third possibility is to see the object of migration aspirations as a matter of personhood or identity. Migrating, then, is not ultimately about where you are, but who you are. Consequently, migration aspirations must be seen as aspirations to embody the figure of the migrant – or rather, the emigrant. This perspective connects the individual and the social in a more dynamic way than the prior two. It is also illuminating in calling attention to ambivalence; works of ethnography and fiction are replete with ambivalent accounts of emigrants as both admired and spurned (Carling 2008).

Cutting across the three types of aspirations is a distinction between migration’s instrumental and intrinsic values (Carling 2012; de Haas 2014). We are used to thinking of migration as an instrumental undertaking: a means to an end, such as personal security, decent work or family co-residence. While such motives clearly matter, migration can be valued – and yearned for – in its own right. Theoretical approaches to migration aspirations must also recognise the pull of adventure, experience and independence.

Accommodating aspirations to stay

So far, we have followed the conventional approach of seeing migration aspirations as something that people either have or do not have. This line of thinking reflects society’s sedentary bias and migration studies’ corresponding mobility bias: sedentary life is the norm and migration is an aberration, demanding explanation. Although staying and leaving are not equal projects – migration generally requires greater effort and resources than staying – both can be an active choice, and under certain conditions, it may be the aspiration to stay that requires explanation. For example, in situations of oppression or occupation, some may decide to stay and resist while others flee. In rural or post-industrial communities threatened by depopulation, staying may represent a statement of commitment. In settings of a ‘culture of migration’ (cf. Kandel and Massey 2002), the volition to stay challenges social expectations and norms about the proper life trajectory. In settings with large-scale out-migration, not migrating may require the most agency and resources.

Aspirations behind staying remain little understood (Schewel 2015). Factors such as attachment to family or socioeconomic embeddedness are assumed, yet in themselves fail to clarify the ‘different ways of staying put’ and why, in similar contexts, we find both involuntary and voluntary immobility (Mata-Codesal 2015).

We identify two approaches for incorporating aspirations to stay into the study of migration. One is to inquire directly about staying preferences or, in survey questions on migration aspirations, to use deliberately balanced wording that presents migrating and staying as equivalent options (cf. Table 1). Another approach is to explore broader life aspirations of individuals and communities, and from this perspective, to analyse how the aspirations interact with perceived opportunities and constraints that give rise to the aspiration to migrate or to stay.

Examining migration ability

When people develop a wish to leave, the outcome depends on their capacity to convert this wish into reality, given context-specific obstacles and opportunities. This elusive confluence of factors is subsumed under the concept of ‘ability’ in the aspiration/ability model. Carling (2002) argued that the greatest barriers to migration are often restrictive immigration policies, particularly for those wishing to migrate from a poor country to a wealthier one. Immigration policies apply unevenly to different social groups or classes (Mata-Codesal 2015; Schiller and Salazar 2013; Van Hear 2014). They tend to facilitate movement of higher skilled people while simultaneously restricting it for low-skilled potential migrants. As legal channels for migration are blocked, the aspiration to migrate finds expression in alternative pathways (e.g. unauthorised migration) or involuntary immobility. Recognising this, we see how the ability to migrate is determined in relation to a particular mode of migration. The same person who cannot acquire a visa and fly legally to Europe may be able to garner enough resources to buy passage on a smuggler’s boat. Depending on the mode of migration, different types of resources – financial, social or human capital – are required to be able to migrate (cf. Carling 2002).

There are essentially two ways to conceptualise migration ability: as potential or revealed. By potential ability, we mean a person’s prospects of realising migration aspirations, regardless of whether the individual has such aspirations in the first place or prefers to stay. Revealed ability, by contrast, is the evident migration ability of someone who has actually migrated. By only discussing ability among people who have migration aspirations, the original aspiration/ability model sidestepped the distinction; it assumed that if aspiring migrants have not yet migrated, it is because they lack ability.

Empirical studies of migration ability are most straightforward when they focus on revealed ability. Several authors have taken quantitative two-step approaches and examined the transition from desired to observed migration. van Dalen and Henkens (2008) and Creighton (2013) made this connection at the level of individuals, while Docquier, Peri, and Ruyssen (2014) connected country-level migration aspirations from the GWP with national migration statistics.

Quantifying whether people would potentially be able to migrate is far more challenging. A multi-country data set, like the GWP one for migration aspirations, does not exist. What comes closest, perhaps, is the Henley & Partners (2015) Visa Restrictions Index which specifies the number of countries that holders of a given national passport can visit without a visa. Several governments also publish acceptance rates, by nationality, for visa applications. These statistics give an indication of differentiated migration ability. Another attempt to quantify migration restrictions worldwide is McKenzie’s (2007) data set on passport costs. He found that in every 10th country, the cost of a passport exceeded 10% of annual per capita income.

Being able to visit another country on a short-term visa is not the same as being able to migrate. But short-term visits often play an important role in migration processes, such as when visitors overstay or make preparations for subsequent long-term migration. Visa restrictions have also had a statistical impact on migration flows (Czaika and de Haas 2016). Figure 3 thus uses data on visa requirements and acceptance rates to illustrate global differences in a key determinant of migration ability. The image is not quite the inverse of the distribution of migration aspirations (Figure 2). Although high-income countries whose citizens enjoy a high degree of travel freedom do not have the least migration aspirations, travel freedom is minimal for citizens of African, Middle Eastern and Caribbean countries, where migration aspirations are most widespread.

Figure 3. Migration ability illustrated through a travel freedom index. The index estimates the percentage of countries to which a citizen of each country would be able to travel. It is based on the assumption that half of the countries where a visa is required (Henley & Partners 2015) can be accessed with a likelihood equal to the average nationality-specific acceptance rate for visa applications to the Schengen Area (European Commission 2016) and the United States (US Department of State 2016), while the other half remains inaccessible. The rationale for the latter point is that the greatest barriers are often posed by the requirements for launching a complete application in the first place.

Connecting with capabilities

The notion of ability resonates with an influential concept in the development literature: capability. The capabilities approach was first introduced by Sen as a people-centred approach to evaluating the ultimate aims of development. In his book Development as Freedom, Sen (1999) argues that the freedom to achieve well-being is a moral imperative, and this should be assessed in terms of people’s capabilities to do and be what they have reason to value. de Haas (2003) applied capabilities as a conceptual refinement to the ‘development’ side of migration-development interactions. Certain capabilities were a precondition for large-scale labour migration, he argued, and migration could in turn further expand people’s capabilities. de Haas (2014) later combined Carling’s aspiration/ability model with the work of Sen into an ‘expanded aspirations-capabilities framework’ that encompasses two-way connections between migration and development.

Capability and ability are essentially synonyms, and they are often used interchangeably in migration research (Dimitriadi 2017; Jayasuriya 2014; Randell 2016). There are subtle theoretical differences, though, between the two terms and their associated theoretical approaches. The aspiration/ability model is a framework for explaining migration outcomes, and ‘ability’ is simply the component that denotes whether prospective migrants can turn their migration aspirations into actual migration. The expanded aspirations-capabilities framework, by contrast, conceives of migration processes as ‘an intrinsic part of broader processes of social transformation’ (de Haas 2014, 4). ‘Capabilities’, in the plural, scopes diverse aspects of well-being. The specific capability to migrate influences migration outcomes, which, in turn, may bolster people’s capabilities in a broader sense through flows of financial, human and social capital.

The capabilities approach suggests that the capability to migrate is a valuable freedom in its own right, regardless of people’s preferences for staying or leaving. Whereas the aspiration/ability model considers ‘ability’ to migrate only among people who aspire to migrate, the ‘capability’ to migrate is, by definition, equally relevant to all.

Identifying acquiescent immobility

The original aspiration/ability model accounted for three mobility categories (cf. Figure 1). Everyone who does not aspire to migrate is ‘voluntarily immobile’ regardless of whether an individual would have been able to migrate. In order to identify those who have neither the aspiration nor the ability to migrate, Schewel (2015) introduced a fourth mobility category: acquiescent immobility. The Latin verb from which the word ‘acquiescent’ derives means ‘to remain at rest’.

Schewel (2015) introduced this mobility category to challenge dominant migration theories – in particular, neoclassical and push–pull models – that implicitly assume the aspiration to migrate is linearly correlated with poverty levels. Part of the assumption is that push factors are greatest for the poor and that migration’s potential income gains are often substantial. Yet, this mobility category highlights that not all poor people desire to migrate. Furthermore, one could question whether immobility is voluntary for those who lack the ability to migrate in the same way it is for those with resources to migrate. The capabilities approach suggests this distinction is important. The emphasis on freedom means that acquiescent immobility is as problematic as involuntary immobility, even if it is not experienced as such by the people concerned.

Looking back at the two maps (Figure 2 and Figure 3), we see countries – China, India and Myanmar, to name a few – where international migration aspirations are rare and citizens face significant restrictions on international travel. Many people in these countries can thus be labelled acquiescently immobile: they would have a hard time migrating but, in any case, prefer to stay. Using EUMAGINE data, Schewel (2015) showed that almost one-third of young adults in Senegal who could not cover their own most basic needs did not want to, even under ideal circumstances, migrate abroad.

How do we understand this preference to stay? Under the category of acquiescent immobility we may find those who have never even imagined migrating – that is, migration does not meaningfully enter into their aspirational horizon or decision-making process. In such instances, an individual may lack the ‘capacity to aspire’ as well as the capability to move (Appadurai 2004; Czaika and Vothknecht 2014; de Haas 2014). From this perspective, it is unsurprising to find acquiescent immobility among the poorest of the poor. But we may also find those who despite having every economic incentive to migrate and an awareness of migration as a possible livelihood strategy, still prefer to stay in their home communities. In these cases, the influence of non-economic values and aspirations – such as the desire to stay with one’s family or to exercise voice instead of exit, to use Hirschman’s (1970) terms – demand attention (Schewel 2015).

Challenging the separation of aspiration and ability

Separating aspiration and ability is the foundational element of the aspiration/ability model, but the two also blur and interact (Carling 2002). In this final section, we raise crosscutting issues that concern their relationship.

First, the relationship between the two core elements involves the interaction of structure and agency. It is essential, however, to go beyond seeing aspiration as a form of agency and ability as a matter of structural constraints and opportunities. The interplay of structure and agency shapes each of the two steps. For instance, the nature of the agency involved in expressing a wish to stay depends on whether it is essentially a default option or a deliberate stance in a setting where ‘everybody’ wants to leave. And the nature of the environment is, of course, a product of other individuals’ attitudes and actions. The very notion of leaving – as an option that individuals can have an opinion about – is socially constructed.

When we recognise the interplay of structure and agency in each step, the aspiration/ability approach can transcend the trap of extremes: either individualism or environmental determinism. The latter pitfall is avoided in part by appreciating aspirations to stay (Schewel 2015). Even in countries such as Liberia, Sierra Leone and Haiti, where half the population would like to leave, the other half wishes to remain. Understanding the role of agency in migration is also about understanding these wishes.

A second form of interaction between aspiration and ability concerns adaptive preferences. In the face of limited migration ability, individuals could react by subconsciously subduing their migration aspirations. Migration aspirations then become even more elusive, for both methodological and theoretical considerations. Within the capability approach, adaptive preferences are widely seen to undermine the value of subjective self-assessments. By extension, one could argue that asking people about migration aspirations is meaningless if they have internalised obstacles to mobility. In fact, a hard-line capabilities approach would pay little attention to migration aspirations altogether, since well-being would be seen to derive from the capability to migrate, regardless of whether it is a desired option. Unyieldingly focusing on capabilities could, in other words, undermine the explanatory power of two-step approaches to migration.

An alternative perspective could be that adaptive migration preferences represent a valuable psychological defence mechanism. If adaptive preferences shift people from a situation of involuntary immobility to one of acquiescent immobility, their subjective well-being might increase. Moreover, they might be more inclined to invest in local futures. Seeing adaptive preferences in such a positive light is pragmatic, but it is a decidedly non-radical position failing to challenge the global inequalities that fuel, shape and constrain migration aspirations in the first place.

The enigmas of adaptive preferences play out in the dynamics of family relationships. There has been a strong interest in families and households as units of analysis in migration research since the 1980s, though the nature of individual agency in family contexts remains a perplexing area for migration theory. Individual aspirations cannot always be disentangled from concerns for kin. And when such commitments discourage migration, it is not obvious whether the effect is about aspirations to stay, or rather, constraints on the ability to move.

Finally, the interaction between aspiration and ability becomes more complex over time. Migration theory has traditionally approached migration as a singular and fundamentally linear event. But in reality, many migrants have a range of potential destinations and pathways available to them at different stages of their journeys. A strand of recent research has engaged explicitly and theoretically with stepwise migration and trajectories. The work of Paul (2011), Wissink, Duvell, and van Eerdewijk (2013) and Schapendonk and Steel (2014) illustrate the potential for analysing aspiration and ability within such processual approaches.

Prospects for migration research

‘Given the increasing complexity and diversity of migration and mobility processes … ’, writes King (2012, 147), ‘all-encompassing theoretical generalisations will become more elusive, although I do not rule them out’. This observation addresses the core challenge for contemporary migration theory: dealing with diversity. There is an understandable tendency towards fragmentation and specialisation, whereby theoretical statements are restricted to certain types of migration contexts. But this approach is vulnerable to how we divvy up a priori the multifaceted and interconnected reality – for instance, in ways that reflect policy categories rather than social dynamics. Moreover, empirical diversity seems to preclude a universal theory of migration.

This analytical impasse calls for theory frames. Such analytical tools provide context and guidance for explaining or formulating hypotheses though stop short of making predictions (Rueschemeyer 2009). The aspiration/ability model is a theory frame for approaching an unknown and diverse migratory reality with migration ‘aspiration’ and ‘ability’ as universally meaningful concepts.

Migration aspirations can take a variety of forms, from lifestyle-driven preferences to urgencies to escape danger, with innumerable possibilities in between. The nature of each person’s migration aspirations is an empirical matter. But migration aspirations can still be examined using concepts such as instrumentality, alternative strategies and steps towards realisation. Beyond migration aspirations, the differentiated constraints on migration ability appear evermore important for actual migration dynamics. A range of outcomes merits attention, including not just actual migration from origin to destination, but the inability to leave in the first place, entrapment in transit and deaths en route – all of which are produced by context-specific and multidimensional manifestations of migration ability.

The current migration regime also represents a political context for analyses. Will greater use of data on millions of prospective migrants in the Global South further provoke restrictivist tendencies? Perhaps. But such data and analyses offer better understandings of migration processes and, potentially, more successful policy engagement with the drivers of migration.

As the demand for compelling and advanced migration research grows, its theoretical foundation remains weak and fragmented. Early on in this article, we identified two-step approaches to understanding migration as a class of research that shares the basic premises of the aspiration/ability model. We then reviewed a range of applications and extensions with diverse theoretical, methodological and disciplinary orientations. In our opinion, these approaches are particularly potent for theorising migration in its contemporary forms and could underpin influential research in the years to come. The aspiration/ability model is not another competing theory to be chosen over others in an already fragmented field. Rather, this model and two-step approaches, more generally, hold the promise of striking a balance between unity and diversity in theoretical approaches to migration.

Acknowledgements

The authors are grateful for valuable comments from Francis L. Collins and Karina Hof. Kerilyn Schewel's research is supported by the MADE (Migration as Development) Consolidator Grant project, funded by the European Research Council under the European Community's Horizon 2020 Programme (H2020/2015-2020)/ERC Grant Agreement 648496.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Jørgen Carling http://orcid.org/0000-0001-5520-3444