View
133
Download
1
Category
Tags:
Preview:
Citation preview
MacroLink
Macro
MicroMicro
Micro-Macro LinkApproach: Lave & March
Micro-Macro LinkApproach: 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.
Micro-Macro LinkApproach: 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
Micro-Macro LinkApproach: 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
Lave & MarchModels
a model is a simplified version of the world
Lave & MarchModels
Models are created by speculating about the process that could have produced the observed outcomes
a model is a simplified version of the world
Lave & MarchModels
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
Lave & March4 steps
1. 2. 3. 4.
Lave & March4 steps
1. 2. 3. 4.Observe
some facts
Lave & March4 steps
1. 2. 3. 4.Observe
some factsSpeculate about the
process that might have produced
such results
Lave & March4 steps
1. 2. 3. 4.Observe
some factsSpeculate about the
process that might have produced
such results
Deduce other results
from the model
Lave & March4 steps
1. 2. 3. 4.Observe
some factsSpeculate about the
process that might have produced
such results
Deduce other results
from the model
Ask if these otherimplications
are true
Lave & MarchExplanation
if this explanation is correct, what else would it imply?
Lave & MarchExplanation
Unexpected Results: if a result was not predicted, other processes must be involved
if this explanation is correct, what else would it imply?
Lave & MarchExplanation
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
Lave & March3 rules of thumb
Lave & March3 rules of thumb
think “process”
Lave & March3 rules of thumb
think “process”
develop interesting implications
Lave & March3 rules of thumb
think “process”
develop interesting implications
look for generality
Lave & Marcha beautiful model
Lave & Marcha beautiful model
simple
Lave & Marcha beautiful model
simple
fertile
Lave & Marcha beautiful model
simple
fertile
unpredictable
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
inSocial Science
Explanation
Explanationin 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
LevelsOf 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
Major Problem
The micro-to-macro Problem
Moving from the lower level to the system level
It is present throughout the social sciences
ExampleResidential segregation
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
Example 1: Residential Segregation
There is few well-mixed composition, mainly blue (very western) and red (very non-western)
There is residential segregation
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?
&
Practical 2
ExampleThomas 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"
There is residential segregationWhy 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 SeggregationSchelling’s
Observe
Speculate
Video
http://www.youtube.com/watch?v=JjfihtGefxk
Residential SeggregationSchelling’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.
Residential Preferences in the USEmpirical 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”
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.
Components of the theoryused in explaining social phenomena
3 components
IndependentMacro-variable
DependentMacro-variable
Input individual choice: Choice options Information Costs and benefits...
Output: Individual choice
Macro relationship
Theory of action
Bridge assumptions
Transformation assumptions
1
2
3
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
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
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
Transition 1Macro-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)
Transition 2Micro-to-Macro
The consequences of the player’s action:
How it combines with, interferes with,
or interacts with
the actions of others
Individual LevelTheory of Action
Rational Choice TheoryNext Lecture
Explanationpurposive 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
Explanationtheory 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.
ExplanationHow 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
The concept ofEmergence
EmergenceIn 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
Example
Think: how do people choose to sit when they come to a conference?
Seating Patterns
Seating PatternsSchelling 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?
Seating Patterns
Think: how did this came about?
First 12 rows
All but first 12 rows
Seating Patterns
Think: how did this came about?
Think: What motivates individual behavior?
First 12 rows
All but first 12 rows
Seating PatternsThink: Is aggregate behavior an extrapolation from the individual behavior?
Seating PatternsThink: Is aggregate behavior an extrapolation from the individual behavior?
LinkMacro
Micro
Micro-Macro LinkIf 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
bBut, 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
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.
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
Seating PatternsUsing: L&M 4 Steps
1
2 speculate
We observe the sitting patternObserve
Seating PatternsUsing: L&M 4 Steps
1
2 speculatea) 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
Seating Patterns
3
4 ask Test the predictions of the model
If (d) is true, then change the position where the lecturer stands
deduce
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)?
Check List1. 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
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.
Comments?
Recommended