A study on effect of corporate diversification on information asymmetry using Bid- Ask: evidence from Tehran Stock Exchange

ABSTRACT:The aim of this paper is to analyze and to test the influence of corporate diversification on the information asymmetry using bid-ask. To test the research hypotheses, a sample of 47 companies listed in Tehran Stock Exchange over the period 2005-2010 based on panel method was taken. In these models, the presence or absence of effects models (fixed or random) is reviewed and finally the best model is estimated. Inference is based on significant level or p-value, thus likely that any value or significance level of the test is less than 0.05 is rejected at the 95 percent confidence level. The results indicate that increasing diversification, reduced information asymmetry