We introduce some new econometric tests and techniques for identifying and overcoming the problem of weak instruments in the context of joint provision of audit and non-audit fees. We use this context because identifying appropriate instruments is difficult due to the lack of theoretical...

We examine how client product similarity within an auditor’s portfolio affects audit efficiency and pricing decisions. Using a unique set of intra-portfolio client-level data, we find that clients with product offerings more similar to those of other clients in the auditor’s portfolio are...