Lakes Research Branch, National Water Research Institute, L7R 4A6, Burlington, Ontario, Canada.
Environ Monit Assess. 1992 Dec;23(1-3):219-42. doi: 10.1007/BF00406963.
Water quality monitoring networks are generally multi-purpose, and thus the data generated are expected to provide information on a set of objectives. Two questions that are fundamental to these objectives are the detection of long term trends and of differences between locations. The extent to which these questions can be answered and the types of statistical methods which can be used are considered in a case study of conventional parameters sampled monthly for nine years. Regression and nonparametric methods, which explicitly account for seasonality, are compared for both the determination of change over time and of differences between locations. Changes over time in the form of step changes and differences between locations which depend upon season were found.
水质监测网络通常具有多种用途，因此生成的数据有望提供关于一组目标的信息。对于这些目标来说，两个基本问题是检测长期趋势和地点之间的差异。在一项针对常规参数进行的为期九年的每月采样案例研究中，考虑了这些问题的可回答程度以及可使用的统计方法类型。针对随时间的变化以及地点之间的差异，比较了明确考虑季节性的回归和非参数方法。发现了以阶跃变化的形式出现的随时间的变化以及取决于季节的地点之间的差异。
