magazine of college Administration&Economics for economic & administration & financial studies

Our proposed method introduces a hierarchical Bayesian regression model with an effective Gibbs sampler for parameter estimation and variable selection. It combines a regularization technique with Bayesian inference by reformulating the Laplace distribution as a mixture of Uniform and Exponential distributions. This mixed distribution is incorporated into the composite quantile regression model to form a new hierarchical model with strong statistical properties.
Through a simulation study, our method outperformed both Bayesian and non-Bayesian approaches in variable selection and estimation. Additionally, it demonstrated excellent stability. When applied to real-world Thrombocytopenia data, our method proved highly effective in both estimating parameters and selecting relevant variables.

The purpose of this study is to examine the effect of internal audit effectiveness on corporate financial performance (CFP) in the private sector of Sulaymaniyah Province, Kurdistan Region, Iraq. Data were collected from a survey that was administered to audit practitioners using an instrument adapted for the purpose of this study and focused on five types of audits: compliance, financial, environmental (or sustainability), IT, and operational. We used IBM SPSS Statistics—Version 23 and conducted Pearson’s correlation and multiple linear regression (OLS) analyses. The internal consistency analysis showed that the instrument was very reliable (Cronbach's Alpha = 0.893), which confirmed the answers given by the participants.
The correlation analysis showed that all aspects of the audit had a positive relationship with the CFP, with IT Audit being the most significant, with r = 0.51, p = 0.000. Financial, environmental, and IT audits had statistically significant positive effects on CFP, while the compliance and operational audit categories did not contribute significantly. The multiple linear regression model explained R² = 0.391 (39.1%) of the variance in firm performance (OLS estimation), displaying moderate explanatory power. These results highlight the strategic value of integrating high-impact audit activities such as financial, environmental, and technology auditing into corporate governance mechanisms. The study suggests that these areas need to be given priority, multicollinearity among the audit functions needs attention, and more research is needed on mediating factors and causal dynamics in auditor-performance relationships.