Variance reduction for trend analysis of hydrochemical data from brackish waters
2003 (English)Report (Other academic)
We propose one parametric and one non-parametric method for detection of monotone trends in nutrient concentrations in brackish waters. Both methods take into account that temporal variation in the quality of such waters can be strongly influenced by mixing of salt and fresh water, thus salinity is used as a classification variable in the trend analysis. With the non-parametric approach, Mann-Kendall statistics are calculated for each salinity level, and the parametric method involves the use of bootstrap estimates of the trend slope in a time series regression model. In both cases, tests for each salinity level are combined in an overall trend test.
Place, publisher, year, edition, pages
Linköping: Linköpings universitet , 2003. , 11 p.
, LiU-MAT-R, ISSN 0349-246X ; 2
IdentifiersURN: urn:nbn:se:liu:diva-22757Local ID: 2076OAI: oai:DiVA.org:liu-22757DiVA: diva2:243070