본 연구의 표본은 시장 특성의 차이를 통제하기 위해 유가증권상장기업만을 대상으로 하였으며 표본기간은 2006년부터 2014년까지(종속변수(t＋1)기준) 9년간이다.
To control the differences in market characteristics, the sample in this study was only for securities-listed companies, and the sample period was from 2006 to 2014 (based on the dependent variable (t+1)) for 9 years.