European Online Journal of Natural and Social Sciences
Abstract
The main purpose of the present research is studying the effect of voluntary disclosure changes on firm value in accepted firms at Tehran stock exchange. Using Feltham and Ohlson's model (1995), the present research has discussed the effect of investors’ reaction to net operating assets and abnormal operating earnings for firms changing their voluntary disclosure. Data analysis was carried out in two steps in this research; at first based on changing in the amount of voluntary disclosure member firms of statistical sample were divided to firms with reduction in disclosure and firms with increase in disclosure then research hypotheses were tested. Results from 420 firm-year during 2006-2011 showed that managers of firms whose firm values are undervalued by investors increase voluntary disclosure of information
