providing a new concept of firm size varible in accounting models

The Firm size of research is measured by indicators such as total assets, stock market value, sales volume, and ... . Different Firm size representatives depict different aspects of company and, as a result, have different interpretations of corporate finances. This study seeks to provide a new concept of Firm size variable used in accounting models and factor expression as a Firm size index including the characteristics of different indicators simultaneously by combining different indicators. In this research, different indicators of Firm size are tested using Exploratory factor analysis and a new factor obtained from the principal components method is presented as Firm size variable. In order to investigate the effect of this factor in improving accounting models, this factor has been tested in earnings management models. For this purpose, a sample of 139 companies for the years 2009 to 2019 has been studied and the results show that using the factor obtained from Exploratory factor analysis improves the results of earnings management models and The results of Kaznik, modified Jones and Jones models are improved and the difference in the time of using the factor is significant compared to the time when only one indicator is used.