Application and Effect Comparison of PCA and PLSDA in TCM Constitution

TCM constitution refers to the individual characteristics of the structure, function, and metabolism formed by the human body on the basis of innate endowments during the growth and development and aging of the day after tomorrow. In this study, 657 people from the community were randomly selected to complete the questionnaire of TCM constitution identification and score.Through the questionnaire, the scores of 9 different constitutions (yang-deficiency, yin-deficiency, qi-deficiency, phlegm-dampness, damp-heat, blood-stasis, characteristic, qi-stagnation and placid) were obtained, and the results of constitution classification were obtained.Then PCA and PLSDA were used to compare different TCM constitutions. PCA and PLSDA are commonly used dimensionality reduction tools, and are now mostly used in statistics, mathematics, and computer science. In this study, we will use PCA and PLSDA to compare different types of TCM constitutions, use PCA and PLSDA's dimensionality reduction ideas to combine different sample data, and to achieve normalized processing of data of different dimension units, so as to construct samples with better properties. Data to better classify different TCM constitutions. This study found that the physique of the peaceful population is very different from that of other constitutional populations. It also provides a scientific and reliable proof for the application of modern data to identify the constitution of traditional Chinese medicine.