Linear and asymmetric interactions of bank and stock market development in the face of global economic uncertainty: a focus on the Nigerian economy

Abstract This study explores the functional interaction between bank development and stock market development in the face of uncertainty variables. The geography of the study is one of the largest economies in Africa—Nigeria—regarding the following variables: credit to the private sector (CPS), broad money (M2) stock market capitalization (MCAP), and industrial production (IP), which are all scaled by the gross domestic product (GDP) and used in natural log form. Additionally, we included the natural logarithm of a measure of monetary policy uncertainty, which represents the uncertainty variable. In terms of methodology, the study uses monthly time series data from 1990:M1-2022M4 (384 observations) and adopts the linear and nonlinear autoregressive distributed lag model. We conclude that both positive and negative changes in policy uncertainty drive bank development. Industrial production did not significantly impact bank and stock market development, and monetary policy uncertainty shows a negative long-run linear relationship with market development. In addition to other significant findings, this study contributes to the literature by demonstrating that monetary policy uncertainty impacts both the stock market and bank development. Given that policy uncertainties impact bank and stock market developments, it is prudent to implement mitigants and safety nets when formulating policies for bank and stock market development.