مهرشاد رمضانی

Social trust is considered as an important type of social capital and in fact an informal institution in any country. The purpose of the present study is to evaluate the impacts of social trust and managers' over self-confidence on the investment efficiency. The general method used in this study had been an applied one in terms of purpose and a correlational and fundamental experimental method type in nature. To achieve this purpose, financial information of 130 companies in the years 2012 to 2021 has been extracted and analysed as the research statistical sample. A linear regression method has been used to test the hypotheses. The research findings showed that social trust has positive, significant positive and negative impacts on the investment efficiency, over-investment and under-investment, respectively. In addition, managers' over self-confidence has positive, significant positive and negative impacts on the investment efficiency, over-investment and under-investment, respectively.