چکیده:
In this research has been examined the relationship between liquidity market changes (i.e. bid-ask spread and depth) as a proxy of information asymmetry around quarterly earning announcements and the percentage of independent directors of board، ownership percentage of institutional investors and internal auditing as corporate governance mechanisms in the firms listed in Tehran stock exchange from 1383-1386 (2005-2008). For examine relationships are utilized Pearson correlation test and Mann-Whitney test for internal auditing hypotheses and spearman correlation test and Kendall’s Tau-b test for percentage of independent directors of board and institutional investors hypotheses. Results indicate that there isn’t meaningful relationship between internal auditing and percentage of independent directors of board and information asymmetry. While، information asymmetry has meaningful relationship with institutional investors. Also via comparison changes of bid-ask spread before and after earning announcements by Wilcoxon test is concluded that level of information asymmetry after announcement is more than before it and this subject is consistent with previous researches.
خلاصه ماشینی:
Master of Accounting, Payam Noor University, Iran (Received: 2023/06/01, Approved: 2023/09/01) Abstract This research examines the relationship between changes in market liquidity (changes in the difference between proposed purchase and sale prices of shares and market depth) around profit announcements as a representative of information asymmetry, and the ratio of non-executive directors on the board, the percentage of ownership of institutional investors, and the internal audit unit as corporate governance mechanisms in companies listed on the Tehran Stock Exchange during the years 2008-2018.
Similar to previous research, liquidity measures (the difference between proposed purchase and sale prices of shares and market depth) have been used as a representative of information asymmetry.
In this research, market depth and the difference between proposed purchase and sale prices of shares (around profit announcements) are used as representatives of information asymmetry41.
The relative difference between proposed purchase and sale prices of shares and market depth are among the liquidity measures that have been investigated in recent research as a representative of information asymmetry11.
's (7002) research show that the average increase in the difference between proposed purchase and sale prices of shares around earnings announcements is less effective for companies with greater board independence and more board activity.
Also, the results obtained from the research do not support the existence of a significant relationship between the ratio of non-executive directors of the board of directors and the variables of proposed price difference and market depth.
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