Wavelet methods have been successfully applied in various issues. They will surely replace gradually the classic methods of cointegration and causality.
The interest of wavalet is that they do not require stationarity and the analysis is done with nonlinear variables.Indeed, there is evidence showing that several economic variables display consistent nonlinear dependencies. But, one common feature to the papers using wavelet analysis is that they rely on univariate and bivariate frameworks. This is equivalent to a simple correlation analysis.
Do we consider the results of these assessments as biased?