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Nature's style: Naturally trendy

January 1, 2005

Hydroclimatological time series often exhibit trends. While trend magnitude can be determined with little ambiguity, the corresponding statistical significance, sometimes cited to bolster scientific and political argument, is less certain because significance depends critically on the null hypothesis which in turn reflects subjective notions about what one expects to see. We consider statistical trend tests of hydroclimatological data in the presence of long-term persistence (LTP). Monte Carlo experiments employing FARIMA models indicate that trend tests which fail to consider LTP greatly overstate the statistical significance of observed trends when LTP is present. A new test is presented that avoids this problem. From a practical standpoint, however, it may be preferable to acknowledge that the concept of statistical significance is meaningless when discussing poorly understood systems.

Citation Information

Publication Year 2005
Title Nature's style: Naturally trendy
DOI 10.1029/2005GL024476
Authors T.A. Cohn, H.F. Lins
Publication Type Article
Publication Subtype Journal Article
Series Title Geophysical Research Letters
Index ID 70027303
Record Source USGS Publications Warehouse