M.A. Thesis:

Ownership structure, audit quality, board structure and stock price collapse

The study of different dimensions of corporate governance and its impact on accounting variables are issues that have been addressed in accounting literature. Corporate governance includes laws, regulations, processes, cultures and systems that lead to goals of accountability, transparency, justice and respect for the rights of the stakeholders. The purpose of this research is to investigate the role of some corporate governance mechanisms in reducing the risk of falling stock prices of listed companies in Tehran Stock Exchange. The focus of ownership, the independence of the board of directors and the quality of the audit are used as components of corporate governance. This research was carried out for a period of 5 years between 92 and 96 years. The sample data of the companies studied after the availability of their information was collected by using the Excel software classification and with the help of the software Ivyz were analyzed and analyzed. The results of the research showed that there is a negative and significant relationship between the concentration of property and the risk of price collapse. Ownership concentration in the hands of one or several major shareholders is a mechanism for controlling firms and has a negative effect on Stock price collapse. There was also a negative and significant relationship between the risk of the collapse of the board of directors and the non-executive directors, who oversee other members of the board of directors and, in the absence of such supervision, may conduct behavioral managers with short-term benefits Consider the term and cause a fall in stock prices. There was also a negative and significant relationship between audit quality and the risk of falling stock prices, quality audits are one of the ways of transferring the information appropriately to external stakeholders, which reduces the cost of representation. To make Reducing agency problems leads to a reduction in bad news about the company and reduces stock collapse. Keywords: risk of price collapse, corporate governance, ownership concentration, audit quality, independence of the board of directors

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