Competition and efficiency in an oligopolistic audit market: Evidence from the Nigerian banking industry

Abstract

Economic theory posits that competition drives efficiency; the extent to which this is true in an oligopolistic audit market poses an empirical challenge. Furthermore, studies have postulated that both traditional and modern industrial organization theories are relevant for analyzing market competition. Therefore, this study investigated the effects of static and dynamic audit market competition on audit efficiency in the Nigerian banking industry. Secondary data were obtained from the audited annual financial statements of 12 banks from 2006 to 2020. The study adopted a 2-stage regression model; in the first stage, the audit efficiency scores were derived from an output-based, variable-return-to-scale version of data envelopment analysis (DEA) comprising audit report lag and audit fees as audit input variables and audit quality as the audit output variable. The efficiency scores were regressed on audit market competition and some control variables in the second stage via the bootstrapped truncated regression technique to analyze the effect of competition on efficiency in the audit market. The results showed a positive association between static competition and audit efficiency (50.57, p = 0.014). Because high concentration implied low competition, this finding implied that efficiency was impaired because of a lack of significant competition. The results also showed a positive and significant association between dynamic competition and efficiency, which implied that dynamic competition enhanced efficiency (0.21, p = 0.000) in the audit market. The study concluded that static competition impairs efficiency, while dynamic competition ensures efficiency in the Nigerian banking industry.