The clarity (or not) of our concepts: migration

This is a migration.

I recently wandered into the conceptual quagmire of migration. I posted previously on concepts and their clarity (or lack thereof), using the example of identity. Please see the first part of that prior post for my discussion of John Gerring's pointers on concept formation in the social sciences.

A caveat here. I am most interested in the topic of migrations or human movements in agrarian state societies. The concepts and perhaps methods differ for non-state societies. In fact the one domain where I found coherent and interesting archaeological work on migration is the U.S. Southwest. For reviews of this work, see: Schachner (2012), or Nelson and Strawhacker (2011); particularly the synthetic chapters.

So, what is wrong with the concept of migration in the archaeology of states? First, many or most archaeologists do not define the term. I was flabbergasted that major programmatic works, published explicitly to promote and refine the concept of migration, do not define the term (Anthony 1990; Burmeister 2000; Frachetti 2011). I took a quick look at other recent works on migration, and didn't see any definitions. It seems that the attitude is that everybody knows what migration is, so why define it. Maybe migration is like pornography - one can't define it easily, but one sure knows it when one sees it.

Is this a migration?

But in the absence of explicit definitions, it seems pretty clear that for most archaeologists, migration means big groups of people moving from one place to another more distant place. Some archaeologists dismiss the notion that shorter or temporary movements constitute migration. These other movements must be something else, but whatever they are, they aren't migration. These more ephemeral movements happen to be the topic of my paper. Now I don't care whether they are called migration or movement or ambulatory transpositional spatial undertakings. But shouldn't there be a way to relate different types of movement to one another without just picking one mode of movement, calling it migration, and ignoring the others? These works remind me of the old country-music song, "That's my story and I'm stickin' to it!"

This narrow approach to definition common in archaeology violates two of Gerring's criteria for productive concept development. First, it produces terminological confusion, by changing the commonly accepted broader definition of migration as many different kinds of movement. This confusion violates Gerring's principle of resonance.

Second, by claiming that only one kind of thing constitutes migration, this narrow definition isolates

Charles Tilly's typology of migration

·        one’s research domain from others, preventing the identification of commonalities or patterns at a more synthetic level. This violates Gerring's principle of differentiation.

To me, a far more productive approach is to look at the broad range of things called migration or movement, and identify the significant variations. Then one can define more limited types or categories based on the important variables. This is just what Charles Tilly (1978) did in a highly influential paper on migration that is not cited by archaeologists or anthropologists.  ((EMAIL ME if you want a copy of Tilly's paper))

People who work intensively on migration will proabably find my ideas simplistic and not useful. But as an outsider wandering into a new body of literature, I was surprised and disappointed at the conceptual confusion. Please define your terms (especially one's central concepts). Please relate your concepts to nearby concepts. And please take a look at Gerring (and at Tilly, if you are interested in migration).

Criteria of conceptualization (Gerring 2012, Table 5.1, p.117)

• 1.      Resonance.  How faithful is the concept to extant definitions and established usage?
• 2.      Domain.  How clear and logical is (1) the language community(ies) and (b) the empirical terrain that a concept embraces?
• 3.      Consistency.  Is the meaning of a concept consistent throughout a work?
• 4.      Fecundity.  How many attributes to referents of a concept share? (coherence, depth, richness, etc.)
• 5.      Differentiation.  How differentiated is a concept from neighboring concepts? What is the contrast-space against which a concept defines itself?
• 6.      Causal utility. What utility does a concept have within a causal theory and research design?
• 7.      Operationalization.  How do we know it (the concept) when we see it? Can a concept be measured easily and unproblematically?

Anthony, David W.
1990    Migration in Archaeology: The Baby and the Bathwater. American Anthropologist 92: 895-914.

Burmeister, Stefan
2000    Archaeology and Migration: Approaches to an Archaeological Proof of Migration. Current Anthropology 41: 539-567.

Frachetti, Michael D.
2011    Migration Concepts in Central Eurasian Archaeology. Annual Review of Anthropology 40: 195-212.

Gerring, John
    2012    Social Science Methodology: A Unified Framework. 2nd ed. Cambridge University Press, New York.

Nelson, Margaret and Colleen Strawhacker (editors)
2011   Movement, Connectivity and Landscape Change in the Ancient Southwest. University Press of Colorado, Boulder.

Schachner, Gregson
2012  Population Circulation and the Transformation of Ancient Zuni Communities. University of Arizona Press, Tucson.

Smith, Michael E.
    n.d.    Urbanization and Village Nucleation: Causes and Consequences of Moving into Town. Unpublished manuscript.

Tilly, Charles
1978    Migration in Modern European History. In Human Migration: Patterns and Policies, edited by William McNeill and R. Adams, pp. 48-74. Indiana University Press, Bloomington.

Why I am posting less frequently this fall

1563 date panel, Calixtlahuaca

Basically, I am incredibly busy right now, leaving me little time for more enjoyable things like blog
posts. Why so busy?

• The Calixtlahuaca project is coming to a close. I am working to make sure all our final analyses get done and paid for before the NSF grant turns into a pumpkin. Among other things, my students and I are hosting a project workshop here at ASU in November, with participants coming in from the U.S. and Mexico to organize our data and thoughts. So why did someone carve both the Aztec and Christian dates in a panel in 1563, when Calixtlahuaca was under the control of Martín Cortés, son of the conqueror?
• Our urban services project is starting up (the NSF grant started in September). Not only are we charting new territory in the GIS analysis of premodern (archaeological and historical) cities, but we are undertaking a massive program of coding historical data to analyze the social, economic, and political context of each city in our sample. The GIS and other technical stuff is the easy work - this coding takes a huge amount of time. My respect for Rich Blanton and Lane Fargher (and the coding they did for Collective Action in the Formation of Pre-Modern States) grows daily. And finding experts to help us with strange old cities, from Zanzibar to Chang'an to Aleppo, can be a real task. So why did the residents of Teotihuacan have to travel much farther (on average) than residents of Tikal, to get to a formal open space for public gatherings?
  
  
• Guess who is the lucky faculty member put in charge of getting our intro archaeology class online! We decided to make this interesting by: (1) combining TWO (2, count em) intro courses--New World and Old World prehistory--into one new course; and (2) getting all of the archaeology faculty co contribute. While that saves me from having to put together class material on, say, the African Paleolithic, it does introduce a certain amount of cat-herding to get everyone to do their part.
  
• I spent a fantastic week at the Santa Fe Institute this summer (I really should post separately on that), and came home all charged up about two new projects. These aren't official things, funded by grants, just research that I am very excited about right now and WANT to spend time on, but can't. Well, I am working on them in small steps, with the help of some students and colleagues. These two projects are:
• Urban scaling. I blogged about this on Wide Urban World. I went to Santa Fe as a skeptic, ready to argue how the scaling models should not apply to ancient cities, but I came home a convert. I really would like to work intensively on this, but no time. Why do social measures (from economic productivity to innovations to crime rates to the number of rock bands in a city) scale at a rate FASTER than basic exponential growth? I am convinced, on theoretical grounds, that this is NOT simply an attribute of modern urban agglomeration economies, but should hold for ancient settlements as well. Now the issue is to gather some data to test this idea. Easier said than done........
  
• Wealth inequality. I worked on this topic early in my career, calculating gini indices for Aztec sites I excavated in the 1980s, and then I largely dropped this when later sites didn't seem to lend themselves to proper sampling for this approach. But then I had a meeting with Sam Bowles at SFI, and he is rooting around for quantitative data (gini indices) on inequality prior to the Industrial Revolution. Bowles is one of my heroes, and talking to him got me excited about generating gini data for two kinds of things: (1) cities in our urban services project; and (2) Aztec data. I've got a student re-doing my earlier gini work (see graph) and applying it to some new datasets. And I'm writing a couple of papers on Aztec inequality.
• And, finally migration. Related to interpreting my rural household data and to the urban scaling research, I am writing a paper on peasant movement and mobility. I quickly discovered that migration is one of the most messed-up topics in the archaeology of complex societies. Almost as bad as identity.  No one defines the term, including basic programmatic papers by people like David Anthony (everyone knows what migration is) and Stefan Burmeister (it might be nice to define migration, but I refuse to do so), and Catherine Cameron (same view as Burmeister). On one level, it is rational to avoid defining migration, because I think it means too many things to be a coherent topic with a theoretical framework, relevant concepts, and such. But then stop claiming that migration or movement IS a thing that archaeologists should study. Rather it is a catch-all for people moving from here to there, which does not seem to be a coherent research domain. So what is the most useful work on "migration" and its constituent forms? - it is an old paper by Charles Tilly that no one  cites! (that is, no one in archaeology or anthropology cites it; the paper is in fac\t widely-cited in historical research on migration). Email me if you want a pdf. (Tilly is another of my heroes.)

Tilly, Charles
    1978    Migration in Modern European History. In Human Migration: Patterns and Policies, edited by William McNeill and R. Adams, pp. 48-74. Indiana University Press, Bloomington.

And, finally, why so long a post if I supposedly don't have time for blogs? Because the alternative is to start grading a big stack of student papers on urban planning in ancient cities.....