Studying Policy Design Quality in Comparative Perspective

Abstract

This article is a first attempt to systematically examine policy design and its influence on policy

effectiveness in a comparative perspective. We begin by providing a novel concept and measure of

policy design. Our Average Instrument Diversity (AID) index captures whether governments tend

to reuse the same policy instruments and instrument combinations or produce policy solutions that are

carefully tailored to the policy problem at hand. Second, we demonstrate that our AID index is a valid and

reliable measure of policy design quality with a strong explanatory power for the outcome variables tested.

Analyzing the composition of environmental policy portfolios in 21OECDcountries, we show that higher

levels of AID are positively associated with a country’s policy effectiveness in environmental matters.

Based on this finding, we analyze, in a third step, the factors that lead countries to adopt more or less

diverse policy portfolios. We find that the policy design quality is significantly improved when policy

makers are not bound by