Thirdly, taking southern California theme parks cluster as a case, we calculate their niche by principle components analysis utilizing the model. 以美國南加利福尼亞州主題公園群落為研究對象，依據主題公園生態位模型，利用主成分分析法進行生態位測度。
The karst area in Guizhou Province was classified into five eco-economic categories by the principal component analysis and fuzzy poly-class method. 摘要運用主成分分析法和聚類分析法，對貴州喀斯特地區的生態經濟類型進行了劃分。
