An Engle-Granger and Johansen Cointegration Approach in Testing the Validity of Fisher Hypothesis in the Philippines

This study contributes to the existing literature and tries to analyze the validity of the Fisher hypothesis in the Philippines. Using monthly data from January 1995 to December 2020, the empirical analysis used the Engle-Granger and Johansen cointegration testing technique. The correlation coefficient suggests a strong positive association. All things being equal, a rise in inflation leads to a rise in the nominal interest rate. The unit-root tests show that inflation and the nominal interest rate are both stationary. Based on both Engle-Granger and cointegrating regression Durbin-Watson tests, the nominal interest rate and inflation are cointegrated. Likewise, the results from Johansen cointegration indicate that there exists a long-run relationship between the variables. However, we rejected a one-to-one relationship between nominal interest rate and inflation. The error correction term coefficient (ECM) shows that it is statistically significant suggesting that the nominal interest rate adjusts to the inflation rate with a lag. The Pair-wise Granger Causality test reported a bi-directional causal relationship between nominal interest rate and inflation. Inflation targeting has been the monetary policy framework of choice for most central banks. In essence, the conclusions of this study are useful to central banks because they help them better comprehend the long-run equilibrium relationship between the nominal interest rate and inflation.