A test for inflation persistence in Nigeria using fractional integration & fractional cointegration techniques

This study seeks to test for inflation persistence in Nigeria using the recently developed fractional cointegration VAR model by Johansen and Nielsen (2012) and complemented with univariate fractional integration techniques. The empirical results suggest evidence of high inflation persistence in Nigeria albeit with a lower trend after the global financial crisis. Also, the major classes of inflation – headline, core and food inflation rates, share long run properties regardless of the sample used. This suggests that any policy action directed at a particular class of inflation will have a spill-over effect on the other classes given the strong association among them. The ability to also exploit the fractional cointegration in a multivariate set-up when modeling inflation is a major contribution of this study and ignoring same may lead to wrong conclusions. However, the results are sensitive to the choice of data frequency.