3. Micro-Macro Link
Approach: Lave & March
In ordinary thinking when we have a result
to explain, we are usually content to think of
some simple explanation and then stop. This is
incomplete thinking; it stops before the
process is fully carried out.
4. Micro-Macro Link
Approach: Lave & March
In ordinary thinking when we have a result
to explain, we are usually content to think of
some simple explanation and then stop. This is
incomplete thinking; it stops before the
process is fully carried out.
The real fun
5. Micro-Macro Link
Approach: Lave & March
In ordinary thinking when we have a result
to explain, we are usually content to think of
some simple explanation and then stop. This is
incomplete thinking; it stops before the
process is fully carried out.
To continue thinking and see what other ideas
the explanation can generate, to ask ourselves: if
this explanation is correct, what else would it
imply?
The real fun
7. Lave & March
Models
Models are created by speculating about the process
that could have produced the observed outcomes
a model is a simplified
version of the world
8. Lave & March
Models
Models are created by speculating about the process
that could have produced the observed outcomes
a model is a simplified
version of the world
Models are evaluated in terms of their ability to
predict correctly other facts
11. Lave & March
4 steps
1. 2. 3. 4.Observe
some facts
Speculate
about the
process that
might have
produced
such results
12. Lave & March
4 steps
1. 2. 3. 4.Observe
some facts
Speculate
about the
process that
might have
produced
such results
Deduce
other results
from
the model
13. Lave & March
4 steps
1. 2. 3. 4.Observe
some facts
Speculate
about the
process that
might have
produced
such results
Deduce
other results
from
the model
Ask
if these other
implications
are true
15. Lave & March
Explanation
Unexpected Results: if a result was not predicted,
other processes must be involved
if this explanation is correct,
what else would it imply?
16. Lave & March
Explanation
Unexpected Results: if a result was not predicted,
other processes must be involved
if this explanation is correct,
what else would it imply?
Human not Individual: good models of human
behavior are rarely precise interpretations of
individual actions
24. Lave & March
a beautiful model
simple
fertile
unpredictable
25. Aims Lecture 3
To explain the relation between the behavior of
individual and the social outcomes
1
2 To present how to construct individualistic
explanations to social phenomena
27. Explanation
in social sciences
The evaluation of a problem is made to the entire
aggregate outcome
Not, merely how each person does within the
constraints of his own environment
The principal task of the social
sciences lies in the explanation
of social phenomena, not the
behavior of single individuals
28. Levels
Of analysis of social phenomena
Examination of the processes internal
to the social system, involving its
component parts, or units at a level
below that of the system
Individual
aggregate
Explaining the behavior of the system by
considering the behavior of its parts
29. Major Problem
The micro-to-macro Problem
Moving from the lower level to the
system level
It is present throughout the social sciences
31. Example 1: Residential Segregation
http://www.nrc.nl/nieuws/2012/02/14/statistiek-saai-cbs-
cijfers-komen-tot-leven-op-een-kaart/
Proportion of niet-westerse allochtonen (non-western immigrants)
The Netherlands has a particular way to trace
in great detail the residential composition: The
postal code (four digits + two letters). This
reduces the composition to units of about 15
households.
Think: How do you expect to see the map colored
The case of Amsterdam
33. There is few well-mixed composition,
mainly blue (very western) and red
(very non-western)
There is residential segregation
34. Does high levels of segregation in a city show that people
want segregated neighborhoods?
This is an important social
phenomenon to be explained
Residential Seggregation
There are political, social, economic implications from it
Can mapping segregation in a city tells us why there is
segregation and what can we do about it?
&
36. Example
Thomas Crombie Schelling
Born in California (USA), 1921
Nobel Economics, 2005
(shared with Robert Aumman)
" For having enhanced our understanding of conflict
and cooperation through game theory analysis"
37. There is residential segregation
Why is there
residential
segregation?
People are xenophobic, and xenophobic people choose to segregate
Does residential segregation
show that people are xenophobic?
http://ccl.northwestern.edu/netlogo/models/Segregation
NetLogo model library - Model: Segregation
What other explanations could there be?
Residential Seggregation
Schelling’s
Observe
Speculate
39. Residential Seggregation
Schelling’s
Even if there are no other mechanisms into consideration (i.e.,
house pricing, income inequality, and off course preferences)
This can be observed in other
places, such as the U.S.
Even if people don’t want to live in segregated
neighborhoods it will emerge as a consequence of individual
behavior.
40. Residential Preferences in the US
Empirical Results on
Clark and Fosset, 2008
The individual level:
Empirical results on residential preferences in U.S.
Data from “Metropolitan
Study of Urban Inequality”
Clark and Fosset, 2008
Their summary:
“The most common response
sets for ideal neighborhoods
are in the range of majority or
near majority same-group
presence.”
Data from Metropolitan Study of Urban Inequality
“The most common
response sets for ideal
neighborhoods are in the
range of majority or near
same-group presence”
41. What have we seen?
It is not straightforwards to say that because individuals can be
satisfied with integrated neighborhoods, there will be integrated
neighborhoods
The interplay of individual actions can bring
about, at the social level, something that is not
really a one-to-one translation.
44. as “games”
Social Phenomena
Consider a Social-Simulation Game
A set of roles that players take on, each role defining the interests or
goals of the player
Social theory represents social problems as the
working out of various rules
Rules about the kinds of actions that are allowable for players in each
role, as well as about the order of play
Individual Roles
Behavioral Rules
45. as “games”
Social Phenomena
Consider a Social-Simulation Game
Social theory represents social problems as the
working out of various rules
Rules specifying the consequences that each player’s action has for
other players in the game
Results Rules
46. of a social system
The game simulates the behavior
Players & the structure of the game
Purposive behavior
(1) Sets in motion the individual actions &
(2) Combines them to produce behavior of the social system
2 Components
Players
The game
47. Transition 1
Macro-to-Micro
All those elements that establish the
conditions for a player’s action:
Personal interests (given by the
goal established by the rules)
Initial condition (context within
which action is taken)
50. Explanation
purposive behavior
In all the speculations there is a notion that people
behave in a way we might call purposive
Goals, purposes or objectives relate directly to other
people and their behavior
We have a mode of contingent behavior - behavior
that depends on what others are doing
51. Explanation
theory based behavior
We use considerations of behavior based on theories
(i.e., Rational Choice Theory)
But, with people it is a hard task to model their
motives
If we consider them as rational maximizers, we
might forget sometimes human limitations and
exaggerate results.
52. Explanation
How to evaluate soc. Phenomena
We use Rational Choice Theory
Infer, from what we take to be the behavior characteristic
of people, some of the characteristics of the system as a
whole
Deduce some evaluative conclusions
54. Emergence
In Schelling’s model we found segregation even though we did
not assume that individuals did want to live in segregated
neighborhoods
Collective phenomena which are
unintended in the sense that individuals
do not seek to create them, are called
emergent phenomena.
the interplay of individual behavior can create patterns which
cannot be directly inferred from motives of the individuals
55. Example
Think: how do people choose to sit when
they come to a conference?
Seating Patterns
56. Seating Patterns
Schelling arrives to give a conference and observes, from
what he could see, that the first 12 rows of the auditorium
were empty
1
2 Thinking the room was empty, when he came in, noticed
that the room was completely full from row 13 on
Think: how did this came about?
60. Seating Patterns
Think: Is aggregate behavior an
extrapolation from the individual
behavior?
Link
Macro
Micro
61. Micro-Macro Link
If we know that at sundown every driver turns his lights
on, we can guess that from an helicopter we can see all
car lights in a local area going at about the same time
a
b
But, if most people turn their lights on when some
fraction of the oncoming cars already have their lights
on, we will get a different picture from our helicopter
62. Micro-Macro Link
In B drivers are responding to each other’s
behavior. People are responding to an
environment that consists of other people
responding to their environment, which
consists of people responding to an
environment of people’s responses.
63. Micro-Macro Link
No simple summation or
extrapolation to the aggregate
Situations in which people’s behavior or people’s choices
depend on the behavior or the choices of other people
65. Seating Patterns
Using: L&M 4 Steps
1
2 speculate
a) Everybody likes to seat as close to the rear as possible
b) Everybody wants to seat to the rear of everybody else
c) Everybody is lazy, so they sit close to the entrance***
d) Everybody likes to seat as far as they can from the
lecturer
We observe the sitting patternObserve
66. Seating Patterns
3
4 ask Test the predictions of the model
If (d) is true, then change the position
where the lecturer stands
deduce
67. Seating Patterns
3
4 ask Test the predictions of the model
If (d) is true, then change the position
where the lecturer stands
deduce
Think: What if we have competing
predictions: say (c) and (d)?
68. Check List
1. We construct models to explain social
phenomena that common sense cannot
account for
2. Social phenomena are modeled and
explained as the interplay between macro
and micro variables
3. The macro outcome is usually emergent
and thus cannot be observed by simple
aggregation
69. In addition
The examples demonstrate that micro level theories
(i.e., rational choice) have the potential to provide
information that we might have overlooked had we
focused on the collective level only.
