Exploratory spectral analysis of hydrological time series

Current methods of estimation of the univariate spectral density are reviewed and some improvements are suggested. It is suggested that spectral analysis may perhaps be best thought of as another exploratory data analysis (EDA) tool which complements rather than competes with the popular ARIMA model building approach. A new diagnostic check for ARMA model adequacy based on the nonparametric spectral density is introduced. Two new algorithms for fast computation of the autoregressive spectral density function are presented. A new style of plotting the spectral density function is suggested. Exploratory spectral analysis of a number of hydrological time series is performed and some interesting periodicities are suggested for further investigation. The application of spectral analysis to determine the possible existence of long memory in riverflow time series is discussed with long riverflow, treering and mud varve series. A comparison of the estimated spectral densities suggests the ARMA models fitted previously to these datasets adequately describe the low frequency component. The software and data used in this paper are available by anonymous ftp from fisher.stats.uwo.ca in the directory pub\mhts

Power asymmetry in conflict resolution with application to a water pollution dispute in C

© 2015. American Geophysical Union. All Rights Reserved. This is the peer reviewed version of the following article:Yu, J., Kilgour, D. M., Hipel, K. W., & Zhao, M. (2015). Power asymmetry in conflict resolution with application to a water pollution dispute in China. Water Resources Research, 51(10), 8627–8645, which has been published in final form at https://doi.org/10.1002/2014WR016257The concept of power asymmetry is incorporated into the framework of the Graph Model for Conflict Resolution (GMCR) and then applied to a water pollution dispute in China in order to show how it can provide strategic insights into courses of action. In a new definition of power asymmetry, one of the decision makers (DMs) in a conflict can influence the preferences of other DMs by taking advantage of additional options reflecting the particular DM's more powerful position. The more powerful DM may have three different kinds of power: direct positive, direct negative, or indirect. It is useful to analyze a model of a conflict without power asymmetry, and then to analyze a power-asymmetric model. As demonstrated by analysis of the water quality controversy that took place at the border separating the Chinese provinces of Jiangsu and Zhejiang, this novel conflict resolution methodology can be readily applied to real-world strategic conflicts to gain an enhanced understanding of the effects of asymmetric power.National Natural Science Foundation of China [71471087]Natural Sciences and Engineering Research Council of Canad