تحلیل تیوریک و تجربی تاثیر هزینه مبادله برتامین مالی از طریق بدهی و سهام در بین شرکت های پذیرفته شده در بورس اوراق بهادار تهران*

Capital is an important source for all of the companies which preparing of that can't be clear, and this reason is one of the factors that make able the financer to control and observe on companies. therefore, the way to prepare financing is an important factor for financial managers. financing traditional method as base on that, the company has no transaction cost related to capital structure, but as williamson (1988) opinion threat finance has important role in finance mechanism in this study, we test these hypotheses using data from companies listed on the tehran stock exchange, during 2000-2010. we run panel regression with stata12 software.we find negative correlation between the asset specificity and financing through debt and a positive correlation between assets specificity and the firms are financed through equity.