This is the code repository for the forthcoming paper: Kacer M., Duboisée de Ricquebourg A., Peel M.J., and Wilson N. (2023) Audit market measures in audit pricing studies: The issue of mechanical correlation. European Accounting Review. The paper shows that in audit pricing studies, the audit market measures derived from the firm-level audit fee are endogenous by construction. This means that their coefficients are biased. Using mathematical derivations, simulations and econometric analysis we explore the extent of the bias but also the bias associated with using the decoupled and size-based measures which are remedies frequently employed in the literature. For replication of the analysis using actual data, you'll need access to WRDS and Stata, version 16 or above. For replication of the simulations, you'll need Stata, version 16 or above. To run the interactive tool, you'll need RStudio. The details of the replication are explained in the paper in Appendix D. If you find the files helpful, please cite the paper:) If you find an error, please let me know by sending an email to m.kacer@leeds.ac.uk Thank you.