유효세율과 기업규모：정치적 비용이론과 정치력이론의 검정

[Purpose] This paper investigates the relation between effective tax rate(ETR) and firm size. Accounting literature offers two competing theories：The political cost theory, suggesting a positive size－ETR relation, and the political power theory, suggesting a negative size－ETR relation. Recent research finds that the ETR for both multinational and domestic firms have been steadily decreasing over recent decades and that multinational firms do not have a tax－based cost advantage relative to their domestic counterparts. [Methodology] This paper examines the relation between firm size and ETR over the past 27 years. In this research, we examine a sample of 3,307 firm－year from 1991 to 2017. Also, we examine the size－ETR relation and ETR for multinational firms relative to domestic firms. [Findings] The results show that we identifying a positive estimates for the size－ETR relation. This finding supports an overall predominance of factors associated with the political cost theory, which predicts a positive size－ETR relation due to greater regulatory actions as well as public pressure and scrutiny on large firms. The significant positive size－ETR relation is not concentrated in multinational firms, a positive size－ETR relation has revealed at approximately the similar way for both multinational and domestic firms. And, we continue to see a significant positive size－ETR relation after controlling for firm characteristics. [Implications] This paper contributes to the accounting research by estimating and comparing a size－ETR relation for domestic and multinational firms. Examining a size－ETR relation help us to better understand possible differences in tax benefits accruing to multinational and domestic firms. And, this paper is important for academic researchers interested in investigating the estimates and he determinants of effective tax rates.