Transcript The Scientific Study of Politics (POL 51)

The Scientific Study of
Politics (POL 51)
Professor B. Jones
University of California, Davis
Today
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Introduction
R…comments about.
Preliminaries/Basic Concepts
Political Science
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Political scientists are interested in
acquiring knowledge about and
understanding many important
political phenomena:
– Many different levels of government
– Many different actors
Political Science
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Political science is the application of
empirical principles to the study of
phenomena that are political in nature.
Empirical Research
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Two reasons to understand how to
conduct empirical research:
– Citizens are confronted with empirical
research daily through political news and
debate.
– You can use empirical research
techniques to improve your own work.
Empirical Research
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Empirical research on political
phenomena can be used to
– Improve understanding of and find
solutions to difficult problems
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Applied research
– Satisfy your intellectual curiosity about
the nature of political phenomena
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Theoretical research
Empirical Research
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The empirical research process of
deciding
– Which information will be used in an
analysis
– Which method will be used to conduct
the analysis
– Which statistic will be used to
demonstrate the findings
Examples of Empirical
Research
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Political scientists study a variety of
questions:
– Winners and losers in politics
– Who votes and who does not
– Repression of human rights
– Public support for U.S. foreign
involvement
What questions are you interested in
studying?
Find a problem!
Is Political Science a
Science?
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There are two general objections to
classifying political science as a
science:
– Practical objections
– Philosophical objections
Is Political Science a
Science?
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Practical objections:
– Political behavior is extremely complex.
– People can intentionally mislead
researchers.
– Measurement is often subjective.
– Data can be difficult or impossible to
attain.
– Data can be “ugly” or misleading
Is Political Science a
Science?
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Philosophical objections:
– The reasoning behind political behavior
cannot be measured objectively.
– The “facts” of political phenomena are
constructed or conditioned by the
observer’s perceptions, experiences, and
opinions.
Political Science
Discipline
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The discipline has changed over time.
– Traditional approach:
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Period between 1930 and 1960—primarily
described the practice of government
– Empirical approach:
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Followed early survey work in the 1950s—led
to the widespread application of statistical
methods—explanatory research
Political Science
Discipline
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The discipline has changed over time.
– Normative pushback:
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In response to empiricism—focused on
questions of morality and policy issues that
are relevant to real- world political discussions
– Debate between empirical and normative
research has cooled since the 1980s
– To engage in modern political science
requires you to understand scientific
method.
Basic Principles
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“Empirical Research”
Hypothesis Oriented
Theory Driven (Hopefully)
Empirically Based
Research
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em·pir·i·cal
– 1.derived from or guided by experience or experiment.
– 2.depending upon experience or observation alone, without using
scientific method or theory, esp. as in medicine.
– 3.provable or verifiable by experience or experiment.
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Observation-based
Data are important!
– Data are not created equal
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Therefore, research design is important
Let’s first think about data…in general terms.
Good Data, Bad Data, Ugly Data
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“Good”
–
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Randomized Samples
Experiments
–
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Convenience Samples
“Person-on-the-Street” Interviews
–
–
Exit Polls (possibly)
“Selected Samples”
“Bad”
“Ugly”
“Archival Data” (all of the above)
Archival Data
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Government Statistics
Historical Data
All very clean data, right?
A Side-Trip to Voting Turnout
Should be easy to measure…
– How do we measure turnout?
Turnout in America
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How has turnout been historically computed?
– Turnout=N Voters/VAP
– VAP: “voting age population” (Now, 18+)
– Problems with this?
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All those 18+ years of age are not eligible to vote.
But still…
Alternative ways to compute turnout?
– Turnout*=N Voters/VEP
– VEP: “voting eligible population” (18+ but legally
permitted to vote)
Turnout: Good Data?
National Voter Turnout
(VAP)
65
63.1
61.9
60.8
Percentage
60
55.2
55
55.3
55.1
53.6
52.6
53.1
51.3
50
50.1
49.1
45
40
1960
1964
1968
1972
1976
1980 1984
Year
1988
1992
1996
2000
2004
Turnout Redux
National Voter Turnout
(VAP vs. VEP)
Percentage
65
60.93
60
55
58.11
54.2
52.6
55.25
53.1
50
55.1
54.22
52.77
51.66
50.1
55.3
51.3
49.1
45
40
1980
1984
1988
1992
1996
Year
VAP
VEP
2000
2004
Tale of Two States:
Arizona
VAP vs. VEP: State of Arizona
65
60
Percentage
55
50
45
40
35
30
25
1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006
Year
VAP:Arizona
VEP:Arizona
Tale of Two States:
California
VAP vs. VEP: State of California
65
60
Percentage
55
50
45
40
35
30
25
1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006
Year
VAP: California
VEP: California
A Tale of Two Countries:
U.S.A. and Australia
National Voter Turnout in Australia (VAP)
90
85
80
75
70
65
60
55
50
45
40
90
85
84.2
84
84.1
82.1
81.2
80
83.4
82.5
81.7
75
63.1 61.9
60.8
55.2
53.6 52.6 53.1
55.3
55.1
50.1
49.1
51.3
Percentage
Percentage
National Voter Turnout in U.S. (VAP)
70
65
60
55
50
45
60 964 968 972 976 980 984 988 992 996 000 004
9
1
1
1
1
1
1
1
1
1
1
2
2
Year
40
1980
1983
1984
1987
1990
Year
1993
1996
1998
Take-away Points?
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Data, even ostensibly clean data, has
measurement issues we must deal with.
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Know your data…US vs. Australia for
example.
A study of turnout differences would be a
silly study.
Have a THEORY…some grounded reason for
your expectations.
Elements of Good Theory
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Generalizability
Replicability
Transparency
Parsimony
– Occam’s Razor
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"when you have two competing theories which make exactly the
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same predictions, the one that is simpler is the better."
"We are to admit no more causes of natural things than such as are
both true and sufficient to explain their appearances." (Sir Issac
Newton)
Theorizing in Social Sciences
can be a bit of Challenge!
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Why do people vote? (Or not vote?)
– Structural Explanations
– Informational Explanations
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Why do states engage in conflict?
– Realist Perspective
– Neorealist Perspective
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Often, multiple “stories” seem
consistent with known facts.
“Laws” are Harder to
Come By
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V=I x R (Ohm’s Law)
– Describes the relationship between
Voltage (V), Current (I), and Resistance
(R)
– It really is a law!
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Anything like this in the social
sciences?
Some “Laws”
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Duverger’s Law:
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Hotelling’s Law:
a principle which asserts that
a majority voting election system naturally leads to
a two-party system. (From Wikipedia)
in many markets it is rational
for producers to make their products as similar as
possible.
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(From Wikipedia)
Perhaps not quite the same as Ohm’s
Law!
Hypotheses and Data
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Y=f(X)
– What is Y?
– What is X? (…or What are the X?)
– What is f()?
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Hypothesis: a statement about how
we think the world works.
Relates x to y.
Causality and Correlation
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Causal explanations are desirable
– “I hypothesize that x “causes” y
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But are difficult to make
– “Stochasticity” (The World is Probablistic!)
– Correlation (“Co-Relation”) is sometimes
the best we can do
Next Time
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Theory, Hypotheses, and Measurement