A Refresher on Theory and Explanation in Sociology Micro-Macro Links in Sociology Werner Raub

1. A Refresher on Theory and Explanation in SociologyMicro-Macro Links in SociologyWerner Raub Workshop on Social Theory, Trust, Social Networks, and Social Capital II National Chengchi University – NCCUApril 2011

2. Agenda for the twointroductory sessions • Basic features of problem-driven and systematic (deductive) theory construction, model building and explanation in social science… • … by way of examples • Focus on micro-macro links in theory and research in sociology • Some “take home messages”

3. Sociological theory according to the “analytical tradition” • Sociology = research on social phenomena (i.e., macro-phenomena) and their social macro-conditions (“causes”); compare Durkheim’s “minimal program” • Sociological theory explains social phenomena by showing how they come about as (often unintended) results of individual behavior that is affected by social conditions.

4. Useful tools for summarizing and reconstructing social science theory and research • Problems as a starting point for theory formation and empirical research P1  T1  E1  P2 ... Problem Theory Empirical Research New Problem • Coleman’s scheme for macro-micro-macro transitions • A scheme representing the structure of social science explanations

5. James Coleman (1926-1995)

6. Coleman’s scheme for macro-micro-macro transitions Social conditions Macro outcomes Macro 1 2 3 Micro Individual effects Preferences, information 1: Bridge assumptions 3. Behavioral theory 2. Transformation rules

7. Coleman’s scheme and the structure of explanations in sociology I 1. General laws Explanans 2. Initial conditions: Social conditions Deduction Description of the phenomenon to be explained Explanandum Social phenomenon

8. Adequacy conditions for explanations • The explanandum is a logical consequence of the explanans. • The explanans contains at least one general law. • The explanans has empirical content (i.e., is testable). • The explanans is true/empirically supported. (See Hempel & Oppenheim, Studies in the logic of explanation, 1948) 48

9. Behavioral theory (arrow 2) Bridge assumptions (arrow 1) Initial conditions Macro-conditions (node A) Micro-conditions (node B) Individual effects (node C) Transformation rules (arrow 3) Additional boundary conditions Individual effects (node C) Collective phenomena and processes (node D) Coleman’s scheme and the structure of explanations in sociology II

10. Three examples • Two highly simplified examples from Coleman 1990, 1987 • Max Weber: the spirit of capitalism • Occurrence of a panic • One more elaborate (though still highly stylized) example • Schelling’s model of residential segregation

11. Max Weber: the spirit of capitalism Protestant religious doctrine Capitalism Macro Micro Economic behavior Values 4

12. The panic example Fire alarm in a crowded theater Panic or order Macro Micro Run to exit / transfer control conditionally Utility structure for alternative actions

13. A somewhat more complex example:residential segregation A sociologically uninformed common-sense theory versus Schelling’s models of segregation

14. Examples of segregation phenomena • Segregation by ... • ethnicity (race) • religion • wealth

15. Residential segregation: a (very) rough definition • Consider a city with X% ‘Whites’ and Y% ‘Non-Whites’ • The city consists of a number of neighborhoods. • ‘Perfect integration’ := Each neighborhood consists of X% ‘Whites’ and Y% ‘Non-Whites’. • ‘Perfect segregration’ := Each neighborhood is either 100% ‘White’ or 100% ‘Non-White’. • Roughly: A city is more integrated, the ‘closer’ the neighborhoods approximate the case of ‘perfect integration.’ And a city is more segregated the ‘closer’ the neighborhoods approximate the case of ‘perfect segregation.’

16. Data on residential segregation:United States, 1940-1960 • Indices of residential segregation by race, 109 cities, for 1940, 1950, 1960. Source: JS Coleman, Resources for Social Change: Race in the US. NY: Wiley 1971, p. 9. The indices are measures of the % of blacks who would have to move in order to achieve residential homogenization by race. An index of 0 would indicate no racial segregation among blocks. A score of 100 would mean that each block is either all white or all black.

17. Data on residential segregation in the US, 2005-2009 • The New York Times offers a resource providing quite up to date and comprehensive data on residential segregation in the US, see: http://projects.nytimes.com/census/2010/explorer • Screening this site is recommended!

18. Residential segregation: some types of problems 1. Descriptive problems - Trends over time - Cross-section: comparing North and South 2. Explanatory problems – our focus Why is residential segregation rather stable over time? Why are there hardly any differences in residential segregation between North and South? 3. Problems of institutional design How to reduce or mitigate residential segregation? 4. Normative problems How much residential segregation is normatively acceptable? What are acceptable costs of reducing or mitigating residential segregation?

19. Residential segregation: possible causes • Actors’ preferences and perceptions • Prejudice • Perception of unwelcome by-effects of integration • Constraints • income inequality / prices on the housing market • legislation Etc.!

20. Common sense-theory % of whites residential approving segregation integration

21. The stability of residential segregation over time: sketch of an explanation Common sense-theory: • percentage of whites residential approving residential integration  segregation  Antecedent condition: • In the US (North and South), the percentages of whites approving residential integration has been appr. constant between 1940 and 1960. ______________________________________________ • In the US (North and South), residential segregation has been appr. constant between 1940 and 1960. Note: We shall see that this explanation is not adequate!

22. Similarities in residential segregation between North and South: sketch of an explanation Common sense-theory: • percentage of whites residential approving residential integration  segregation  Antecedent condition: • In the US (between 1940 and 1960), there are no systematic North-South differences in the percentage of whites approving residential integration. ______________________________________________ • In the US (between 1940 and 1960), there are no systematic North-South differences in residential segregation. Note: We shall see that this explanation is not adequate!

23. Science as a systematic test of theories

24. The logic of empirical tests of theories 1 Propose a theory / hypothesis 2 Derive empirically testable implications 3 Compare these implications with data 4.2 Refutation of the theory 4.1 Corroboration of the theory

25. Table I-3 and I-25 combined. Indices of residential segregation by race, 109 cities, for 1940, 1950, 1960, and percentage of whites who approve residential segregation in 1942, 1956, June and December 1963, 1965, 1968ª ª Source: For residential segregation see Table I-3. For attitudes towards residential integration the question asked was, “ If a Negro with the same income and education as yours moved into your block, would it make any difference to you?” Data on 1942, 1956, 1963 from Paul B. Sheatsley (1996, Table I, p. 222). Data on 1965, 1968 by personal communication from Paul B. Sheatsley (July 1, 1969) unpublished data from NORC surveys of October 1965 and April 1968.

26. An empirical test of the common sense- theory of residential segregation 1. Common sense-theory (hypothesis): % of whites residential approving residential integration  segregation  2. Implications: Trend: If the percentage of whites approving integration increases in the US (North and South) between 1942 and 1956 as well as between 1956 and 1963, then residential segregation decreases in the US (North and South) in both periods. Comparison North-South: If the percentage of whites approving integration is higher in the North than in the South of the US in the forties, fifties, and sixties, then residential segregation is lower in the North than in the South of the US in all three periods. 3. Comparison with data (from Coleman, 1971 and Sheatsley, 1966). 4. Refutation of common sense theory of residential segregation.

27. Schelling’s models of segregation

28. Thomas Schelling

29. Residential segregation:summary of the problem situation

30. Schelling’s game • Initial state (residential integration) • Unidimensional town: from left to right, 70 pieces (households) are spread out in a line. • Two ethnicities: each piece is black or white • The color of each piece is decided by throwing a dice. • 1,2,3: black piece • 4,5,6: white piece

31. oo#o#oo## Neighborhood 2. Definition of the neighborhood of a piece (neighborhood of a household) • The neighborhood of a piece consists of the piece itself, the four pieces to the left, and the four pieces to the right • Pieces near the end of the line have less neighbors (alternative: circle)

32. Neighborhood and interdependence • Neighborhood of a piece = neighborhood of a household • Note: interdependence between households: if A and B are neighbors, (color of) A affects composition of B’s neighborhood and vice versa • Interdependence as a social condition for residential segregation in addition to preferences and perceptions of actors

33. 3. Moving pieces I • The game proceeds in rounds (segregation as a dynamic process). • At the beginning of each round, each piece in a neighborhood where more than half of the neighbors have the opposite color is marked • Preferences of households: avoid a minority situation • Social condition: composition of neighborhoods • Individual motives (avoiding a minority situation) versus collective effects (segregation) • Order of moving: marked pieces move in turn, counting from left to right.

34. Moving pieces – interpretation • The preference of households to avoid a minority situation is consistent with different more specific assumptions: • One prefers segregated over integrated neighborhoods (“white prejudice”) • One prefers an integrated (50-50) neighborhood to any other other composition as long as one is not in the minority situation (“preference for residential integration”) • One is indifferent with respect to to neighborhood composition as long as one is not in the minority situation • Hence, Schelling’s rules and assumptions are consistent with the assumption of preferences for integration!

35. An observation on the “spirit” of Schelling’s models • Schelling’s rules and assumptions are in a sense very “optimistic” with respect to “prospects for residential integration” • He tries to show precisely that extreme residential segregation can emerge even under seemingly favorable conditions for integration • Complex relationship between individual motives (avoiding minority situation) and collective effects (extreme residential segregation) • Residential segregation as an unintended and unfavorable (suboptimal) outcome for the actors

36. Moving pieces II • How pieces move: a piece moves to the nearest point between two other pieces to the right or to the left where it is not a minority. • Interpretation • Moves are costly; costs increase in distance • No scarcity on the housing market • No legal or economic constraints to choosing certain neighborhoods • No discrimination on the housing market

37. Moving pieces III • If the neighborhood of a marked piece has changed such that not more than half of the neighbors have the opposite color when the turn to move comes, the marked piece does not move after all - Interdependence between households. • End of a round: each piece that has been marked at the beginning of the round has had a turn to move • End of the game: each piece has a neighborhood with at least half of the neighbors of the same color (or: there are no suitable places to move to)

38. Example (compare Schelling 1969: 490, 1971: 149-151) 1. Start situation: o#ooo##o#oo##oo###o##o##oo##oo##oo##o#o#oo###o##ooooo###ooo#oo##o#o##o • Situation after round 1 oooooooo####o#########oooo##ooo#o#o###o#########oooooooooooooooo###### 3. Situation after round 2 oooooooo###############oooooooooo###############oooooooooooooooo######

39. Important features of Schelling’s model • The model shows that high levels of segregation can result from rather tolerant individual preferences • High levels of segregation can result from both tolerant and intolerant preferences • Schelling makes the micro-macro link explicit • The model allows for derivation of new implications

40. “Changing support for integration” and “differences in support for integration” • Background: the data on residential segregation for the United States • Question: how to conceptualize “increasing support for integration within a region” and “differences in support for integration between regions” within Schelling’s model?

41. “Changing support for integration” and “differences in support for integration” • Consider the following preferences for neighborhood composition that are all consistent with a 50%-threshold for moving: Most preferred is... • complete segregation... • much segregation... • some segregation... • perfect integration... and in all cases 1 – 4 one moves as soon as one is in the minority position • Clearly, “support for integration” increases when preferences shift from 1 to 4 • NOTE: under each of the 4 types of preferences, extreme segregation results 36

42. Schelling’s model versus the “common sense theory” • Schelling’s model improves on the common sense-theory in two respects: • Empirically: Schelling’s model is consistent with a ‘weak’ relation between prejudice and segregation. • Over time increasing support for integration need not reduce segregation. • Two regions that differ with respect to support for integration can be similar with respect to segregation levels. • Theoretically: Schelling’s model (but not the common sense-theory) is consistent with the “minimal program of sociology”: explaining macro-phenomena as a result of macro-conditions and incentive-guided (goal-directed) behavior

43. Table I-3 and I-25 combined. Indices of residential segregation by race, 109 cities, for 1940, 1950, 1960, and percentage of whites who approve residential segregation in 1942, 1956, June and December 1963, 1965, 1968ª ª Source: For residential segregation see Table I-3. For attitudes towards residential integration the question asked was, “ If a Negro with the same income and education as yours moved into your block, would it make any difference to you?” Data on 1942, 1956, 1963 from Paul B. Sheatsley (1996, Table I, p. 222). Data on 1965, 1968 by personal communication from Paul B. Sheatsley (July 1, 1969) unpublished data from NORC surveys of October 1965 and April 1968.

44. Some further questions on Schelling’s models • Does segregation always emerge? And how stable is integration? • Integrated initial states#0#0#0#0#0 ... 0#0#0#0#0# ... ... • Probability for such states is very small • These states are unstable under “external shocks” such as “forced movements” or in- and out-migration of households • Note: the final states in Schelling’s model are stable relative to such “external shocks

45. Schelling’s model: unrealistic and simplifying assumptions • One-dimensional town • Order of moving • Two groups of similar size • Homogeneity assumption with respect to: • Neighborhood size • Preferences of neighborhood composition • No scarcity on the housing market • No legal or economic constraints to choosing certain neighborhoods Problem: derive implications of more realistic and less simplifying assumptions

46. A two-dimensional variant Initial Situation Resulting Situation

47. Reconstruction of Schelling’s model

48. Schelling’s model and Coleman’s scheme

49. Social change in Coleman’s scheme

50. Recent literature on residential segregation • Fossett, Mark (2011) Generative models of segregation: Investigating model-generated patterns of residential segregation by ethnicity and socioeconomic status, forthcoming in Journal of Mathematical Sociology 35(1) – up to date extension of Schelling-type models; will be available on Studion • Bruch, Elizabeth & Robert Mare (2009) Segregation Dynamics, pp. 269-293 in Peter Hedström & Peter Bearman (eds.) The Oxford Handbook of Analytical Sociology, Oxford: Oxford University Press.