1. Open Legislative Data - Science Po 2012 Dirk Junge dirk.junge@uni-mannheim.de and Daniel Finke daniel.finke@uni-heidelberg.de Bargaining in Legislatures: How Parliaments Shape Policy Proposals and What Legislative Behavior Can Tell us About That

2. Background Much progress has been made in legislative research in understanding the adoption of laws, the duration of legislative negotiations and the patterns of interests in parliaments But still lack of information on one important element in quantitative legislative research: characteristics of policy proposals on the floor indispensable for understanding how lawmaking in parliaments works: how do parliamentary actors shape policy outcomes in legislative negotiations in different legislative systems? what are the policy effects of different decision making procedures in legislative negotiations? to what extent and how do legislative outcomes represent the interests of parliaments and how does the representation of interests differ across legislatures?

3. Problem difficult to “measure” policy proposals and their decision relevant characteristics in quantitative analyses directly difficult to do qualitative analyses in large N studies but: indirect inferences possible from legislative behavior?

4. Idea Legislative behavior reveals not only information on legislative interests but also on attitudes towards policy proposals within given institutional constraints. We can often distinguish the interest- and policy component due to different levels of variation if the institutional constraints are known. This idea can directly be implemented in IRT models (Clinton 2004) ->interests and policy proposals can be estimated as latent variables of legislative behavior in a common policy space that best explains legislative behavior Example: Bargaining on the Services Directive in the EP

6. Discussion - Positive provides detailed information on interests and policy proposals in legislative bargaining processes allows for direct and detailed tests of bargaining and agenda-setting theories works with most types of behavioral data and allows to combine them: Individual votes, initiatives of laws and amendments, sponsorship, behavior of parties and behavior of committees data required is often easy to access (or has already been collected) works for quantitative analyses and can be automated matches interests and policy proposals in the way most consistent with legislative behavior reports uncertainty about inferences in a straightforward manner

7. Discussion - Negative Different types of available data create different levels of uncertainty in different countries Does not work in case of single party majority governments with strong party discipline (variation of legislative behavior and successful proposals required for estimation) Estimation requires massive computational power: equation systems with thousands of variables and no unique global solution (“identification problem”) little is known about the distributions of variables a priori (lack of “closed form” solutions) estimation cannot be parallelized effectively

8. Conclusion IRT extensions powerful approach to assess how parlaments work and how they shape policies in legislative negotiations? quantitative inferences possible for many countries with precise information on uncertainty of inferences main limitation is computational power – simplifications often required for large scale applications