kamil gregor: a bayesian model of ecological inferece (presentation for the 2012 eusoc conference)

„Crazy 90s and boring 00s?“:The Stability of Structure of Individual-level behaviour

in the Czech Republic

Kamil Gregor

Why my paper sucks?

Why my paper sucks?

Why my paper sucks?

The method…

Ecological inference problemBlacks Whites Total

1000600 400

? ? 400 Voters

? ? 600 Non-Voters

Ecological inference problemBlacks Whites Total

1000600 400

? ? 400 Voters

? ? 600 Non-Voters

Blacks Whites Total1000600 400

0 400 400 Voters

0 0 600 Non-Voters

Ecological inference problemBlacks Whites Total

1000600 400

? ? 400 Voters

? ? 600 Non-Voters

Blacks Whites Total1000600 400

0 400 400 Voters

0 0 600 Non-VotersBlacks Whites Total

1000600 400

400 0 400 Voters

200 400 600 Non-Voters

Blacks Whites Total1000600 400

200 200 400 Voters

400 200 600 Non-Voters

Basic Statistical Undeterminacy Problem

Pi = AiDi + Bi(1 – Di)

Whites BlacksTotal

1Pi 1 – Pi

Ai Di – Ai Di Voters

Bi(1 – Di) – Bi 1 – Di Non-Voters

How to solve an unsolvable problem?

• Surveys – sometimes unavaliable– Lack of resources– Unreliable responces– Ex post research (I do not see dead people)

• Statistical models

The model

Data Model Results

Model assumptions

• No changes in population• (No spatial autocorrelation)• A distribution of unobserved variables

corresponds to an a priori chosen distribution

Binomial Normal Distribution

Bayesian models

• Utilizing information on the distribution of observed variables to better assume a distribution of unobserved vatiables

What is it good for?

• When dealing with aggregate data• Filling cells in a contingancy table

A B C

? ? ? α

? ? ? β

? ? ? γ

Examples in political science

• Social, economic and demographic characteristics of a population (e.g. an electorate of a political party)

• Voter transitions between elections• Ticket-splitting

…and what to do with the method

Research question

• What the hell is going on?• The process of party system structuralization

in Central Europe in 1990s and 2000s• Central European party systems appear to be

unstructuralized but there might be a „hidden“ structure

• „Parties come and go but the structure remains the same (?)“

Research question

• Is there a stable underlying structure of electoral behaviour in Central Europe?

• The question is whether voters continually vote for political parties that occupy relatively similar position in a political space

The thesis

• V4 countries• Parliamentary elections since early 1990s• Voter transition rates between political parties

in pairs of consequential elections

The thesis

Non-voters VVČSSD KDU-ČSL KSČM ODS SUV SZ TOP09

Non-voters

ČSSD

ODS

KSČM

KDU-ČSL

SZ

Other

A conceptualization of political space

An old leftist party

An old rightist party

An old rightist party

An old leftist party

A new leftist party

A new leftist party

An old rightist party

An old rightist party

Model A

An old leftist party

An old rightist party

An old rightist party

An old leftist party

A new leftist party

A new leftist party

An old rightist party

An old rightist party

Model B

An old leftist party

An old rightist party

An old rightist party

An old leftist party

A new leftist party

A new leftist party

An old rightist party

An old rightist party

1

Model C

An old leftist party

An old rightist party

An old rightist party

An old leftist party

A new leftist party

A new leftist party

An old rightist party

An old rightist party

Model D

An old leftist party

An old rightist party

An old rightist party

An old leftist party

A new leftist party

A new leftist party

An old rightist party

An old rightist party

Operationalization

• How to operationalize ideology?• How to operationalize „new“ and „old“?• Are these two concepts sufficient to describe a

political space?

Possible results

• „Crazy 1990s“ and „boring 2000s“?– Lack of structure in the 1990s and stability in

2000s• Why?

– Relative unexperience of voters– „Crystalization“ of parties‘ ideological profiles

https://docs.google.com/spreadsheet/pub?key=0Asva5SIBKjNudF9oUUc2MjNmMXYzN29KNmtCd2tZTmc&gid=1

Thanks for your attention

Kamil Gregorkamil.gregor@gmail.com