Hani Gharavi Ahangar - Department of Accounting, Qaemshahr Branch, Islamic Azad University, Qaemshahr, Iran
Seyedhossein Naslemousavi - Department of Accounting, Qaemshahr Branch, Islamic Azad University, Qaemshahr, Iran
Ali Akbar Ramezani - Department of Accounting, Qaemshahr Branch, Islamic Azad University, Qaemshahr, Iran

Credit ratings reflect the relative ability of companies to meet their financial obligations, the relative default probability, and the recovery probability if the debt is not paid. Credit rating agencies build their information analysis on financial statements, which directly affect the credit rating. Tax activities, meanwhile, may contain useful information for credit rating agencies due to their essential role in influencing corporate credit. Thus, the study aims to investigate corporate tax avoidance's effect on credit rating using the Particle swarm Optimization (PSO) algorithm. Therefore, to achieve the research goal, ۱۰۱ sample companies were collected in ۹ years from ۲۰۱۱ to ۲۰۱۹. The emerging-market scoring model measured credit rating and tax avoidance using two scales of tax-book difference and effective tax rate. The Statistical test related to the results indicates relationships. It is significant between tax avoidance and credit rating.

Credit ranking, Tax avoidance, PSO algorithm