School of Environmental Studies, China University of Geosciences, No. 68 Jincheng Street, Wuhan 430078, China.
Technology Innovation Center of Geo-Environmental Restoration, Ministry of Natural Resources, No. 388 Lumo Road, Wuhan 430074, China.
Int J Environ Res Public Health. 2020 Dec 18;17(24):9515. doi: 10.3390/ijerph17249515.
Traditional methods for hydrochemical analyses are effective but less diversified, and are constrained to limited objects and conditions. Given their poor accuracy and reliability, they are often used in complement or combined with other methods to solve practical problems. Cluster analysis is a multivariate statistical technique that extracts useful information from complex data. It provides new ideas and approaches to hydrogeochemical analysis, especially for groundwater hydrochemical classification. Hierarchical cluster analysis is the most widely used method in cluster analysis. This study compared the advantages and disadvantages of six hierarchical cluster analysis methods and analyzed their objects, conditions, and scope of application. The six methods are: The single linkage, complete linkage, median linkage, centroid linkage, average linkage (including between-group linkage and within-group linkage), and Ward's minimum-variance. Results showed that single linkage and complete linkage are unsuitable for complex practical conditions. Median and centroid linkages likely cause reversals in dendrograms. Average linkage is generally suitable for classification tasks with multiple samples and big data. However, Ward's minimum-variance achieved better results for fewer samples and variables.
传统的水化学分析方法虽然有效，但种类较少，且受到限制，只能应用于有限的对象和条件。由于其准确性和可靠性较差，这些方法通常用于补充或与其他方法结合使用，以解决实际问题。聚类分析是一种从复杂数据中提取有用信息的多元统计技术。它为水地球化学分析提供了新的思路和方法，特别是对于地下水水化学分类。层次聚类分析是聚类分析中最常用的方法。本研究比较了六种层次聚类分析方法的优缺点，并分析了它们的对象、条件和适用范围。这六种方法是：单链接、完全链接、中位数链接、质心链接、平均链接（包括组间链接和组内链接）和 Ward 的最小方差。结果表明，单链接和完全链接不适合复杂的实际情况。中位数和质心链接可能导致树状图反转。平均链接通常适用于具有多个样本和大数据的分类任务。然而，Ward 的最小方差在样本和变量较少时效果更好。
