Towards a green state: A comparative study on OECD countries through fuzzy-set analysis

This study aims to develop an empirical measurement framework of the green state and compare twenty-four OECD (Organization for Economic Cooperation and Development) countries' cases through the fuzzy-set multiple conjunctural analysis and the ideal type analysis. Based on the analysis model of the outcome set (Sustainable Development Goal Index) and the causal sets of seven variables on the four green state categories ('ecological authoritarian state', 'ecological modern state', 'ecological democracy state', and 'ecological welfare state'), this study reveals the following results. Among OECD member countries, if ones have high environmental tax, high environmental innovation (patent), high economic development and democracy, high levels of environmental governance and social expenditure, or have high economic development and democracy, and high levels of environmental governance and environmental health, they can be seen to have reached a high level of green state (consistency: 0.980, total coverage: 0.675). Also, the thirteen ideal types of green state of twenty-four OECD countries were derived. Norway (fuzzy-set membership score of 0.515) is a country of Type 1, with a characteristic of 'strong green state' having all high features of the four green state categories. Greece (membership score, 0.692) and Ireland (0.577) belong to Type 13, characterized by 'weak green state' with all four low features. As a result, the green state types of the twenty-four OECD countries can be assorted into five levels: 'Strong Green State', 'Quasi-Strong Green State', 'Quasi-Green State', 'Quasi-Weak Green State', and 'Weak Green State'.