An open-source wavelet tool for improving prediction accuracy for natural system models.

The wavelet-based variance transformation method is used for system modelling and prediction. It refines predictor spectral representation using Wavelet Theory, which leads to improved model specifications and prediction accuracy.


  waveslim, stats, tidyr, ggplot2, sp

    zoo, readr,
    cowplot, SPEI, FNN, 
    NPRED, synthesis, fitdistrplus


You can install the package via devtools from GitHub with:

devtools::install_github("zejiang-unsw/WASP", dependencies = TRUE)

or via CRAN with:



Jiang, Z., Sharma, A., & Johnson, F. (2021). Variable transformations in the spectral domain – Implications for hydrologic forecasting. Journal of Hydrology, 603, 126816. doi

Jiang, Z., Rashid, M. M., Johnson, F., & Sharma, A. (2020). A wavelet-based tool to modulate variance in predictors: an application to predicting drought anomalies. Environmental Modelling & Software, 135, 104907. doi

Jiang, Z., Sharma, A., & Johnson, F. (2020). Refining Predictor Spectral Representation Using Wavelet Theory for Improved Natural System Modeling. Water Resources Research, 56(3), e2019WR026962. doi