Review of income smoothing models and evaluating of income smoothing behavior with emphasis on accounting variables

This research intends to compare accounting variables in accepted income smoother and non-income smoother firms in Tehran stock exchange. For this reason, at first, based on models of income smoothing behavior of Mcleoz, Eckel, Kothary& Leone, statistic typical companies were separated to income smoother and non-income smoother firms then accounting variables were compared. Five features including firm size, costs of staff, debt ratio, management bonus, tax as independent variables and income smoothing behavior as dependent variable are examined. This research has done based on annual observations (2006-2011). Results show that in level of each three model (Mcleoz, Eckel, kothari&Leone) there is meaningful difference between size of income smoother and non-income smoother firms. In relation with debt ratio variable just in level of Mcleoz model there is meaningful difference between smoother and non smoother firms and in level of two models (Eckel, kothari&Leone) meaningful difference is not observed. Also In relation with tax variable just in level of Eckel model there is meaningful difference between income smoother and non-income smoother firms and in level of two models Mcleoz, Kothari&Leone meaningful difference is not observed. Also with attention to research finding in level of each three model (Mcleoz, Eckel, Kothari&Leone)there is no meaningful difference between costs of staff and management bonus of income smoother and non-income smoother firms .Result of others research finding show that among of two model of above , Eckel, Kothari&Leone model in categorizing income smoother and non-income smoother firms is better than Mcleoz model and there is no meaningful difference about categorizing between Eckel and Kothari&Leone model.