조세비용과 비조세비용이 기업가치에 미치는 영향：세무계획 효과성을 활용한 분석 연구

[Purpose] The purpose of this study is to identify the effects of both tax and non－tax costs on firm value, using tax planning effectiveness as a measure. [Methodology] This study uses a sample of 9,415 firm－year observations from non－ financial firms listed on the KOSPI and KOSDAQ markets. First, it measures tax planning effectiveness using data envelopment analysis (DEA), and then derives the variable for non－ tax costs from this measure. Using both the non－tax cost variable and the tax cost variable, measured by the cash effective tax rate, the study examines the effects of these two factors on firm value. [Findings] The results of the analysis indicate that lower tax costs and higher non－tax costs are associated with a decrease in firm value (Hypothesis 1). These results suggest that low tax costs, that is, tax avoidance negatively affects investors for being perceived as business risks. Furthermore, this study confirms that sound governance structures mitigate non－tax costs, thereby weakening the negative relationship between non－tax costs and firm value (Hypothesis 2). Therefore, firms need to strengthen governance mechanisms and control systems that monitor executives’ pursuit of private gains and manage tax risks. [Implications] The present study provides the following implications. First, this study contributes to advancing tax accounting research by utilizing a measure of tax planning effectiveness. Second, it contributes to related research by designing a comprehensive variable that measures the overall level of non－tax costs. The non－tax cost variable measured in this study is expected to aid in future research aimed at identifying the characteristics of firms that incur higher or lower non－tax costs.