We propose that institutional differences in executive-legislative relations generate heterogeneity in the creditworthiness of democracies in the sovereign credit market. In particular, there is a credibility advantage for parliamentarism relative to presidentialism, because the former, with stronger parties, elongates policy-makers’ time horizons and lowers their discount rate, thereby enhancing their ability to signal the credibility of their commitment to debt repayment. Our Heckman selection analysis of democracies from 1990 to 2012 confirms the existence of parliamentary advantage in sovereign credibility, and it also reveals a semi-presidential advantage relative to presidentialism. Our study contributes to the recent stream of research that problematizes the democracy/autocracy dichotomy in the study of sovereign credibility.

中文翻译：

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主权信用市场的议会和半总统优势：民主制度设计和主权可信度

我们提出行政-立法关系的制度差异导致主权信用市场中民主国家信用度的异质性。特别是，议会制相对于总统制具有可信度优势，因为前者拥有强大的政党，可以延长决策者的时间范围并降低其贴现率，从而提高他们表明其偿还债务承诺的可信度的能力。我们对 1990 年至 2012 年民主国家的 Heckman 选择分析证实了议会在主权可信度方面的优势，也揭示了相对于总统制的半总统制优势。我们的研究有助于最近在主权可信度研究中对民主/专制二分法进行问题化的研究。