Power of non-parametric Mann-Kendall test and Spearman’s Rho test is highly influenced by serially correlated data. To address this issue, trend tests may be applied on the modified versions of the time series data by Block Bootstrapping (BBS), Prewhitening (PW) , Trend Free Prewhitening (TFPW), Bias Corrected Prewhitening and Variance Correction Approach by calculating effective sample size.
Mann, H. B. (1945).
The package is useful in implementing Non-parametric Mann-Kendall trend tests and Spearman's Rank Correlation Coefficient tests.
The package contains the following varians of Trend-Tests
Mann-Kendall trend test (MK)
Mann-Kendall trend test for Pre-Whitened series (PW-MK)
Mann-Kendall trend test for Bias-Corrected Pre-Whitened series (BCPW-MK)
Mann-Kendall trend test for Trend-Free Pre-Whitened series (TFPW-MK)
Block Bootstrapping with Mann-Kendall test (BBSMK)
Modified Mann-Kendall trend using Variance Correction Approach by Hamed and Rao (1998)
Modified Mann-Kendall trend using Variance Correction Approach by Hamed and Rao (1998) considering significant lags upto lag-3
Modified Mann-Kendall trend using Variance Correction Approach suggested by Yue and Wang (2004)
Modified Mann-Kendall trend using Variance Correction Approach suggested by Yue and Wang (2004) considering only lag-1 auto correlation coefficient
Spearman's Rank Correlation test
Block Bootstrapping with Spearman's Rank Correlation test (BBSSR)
Trend magnitude is calculated by Sen's slope method