Principal Component Analysis is a statistical technique used to identify correlations among data. Its spelling is determined by its pronunciation, which is transcribed as /ˈprɪnsəpl/ /kəmˈpoʊnənt/ /əˈnæləsɪs/. The first syllable "prin" pronounced as /prɪn/ is derived from the word "prince." The second syllable "-ci" pronounced as /sə/ is the "unstressed vowel" sound. The third syllable "pal" pronounced as /pəl/ is from the word "pal." The fourth syllable "-com" pronounced as /kəm/ is from the word "component," and the fifth syllable "-po" pronounced as /ˈpoʊ/ is from the word "pose." Finally, the last syllable "-nent" pronounced as /
Principal Component Analysis (PCA) is a widely utilized linear dimensionality reduction technique that aims to transform a higher-dimensional dataset into a lower-dimensional space while retaining most of the variance present in the original data. It is a statistical tool that can be employed to highlight the critical features and patterns within a dataset in order to facilitate subsequent analysis.
PCA deals with finding a set of orthogonal axes, termed principal components, that captures and explains the largest amount of variance in the data. These principal components are constructed in a way that the first component accounts for maximum variance, followed by the second component accounting for the maximum variance left, and so forth. Each principal component is a linear combination of the original variables that are decorrelated from each other.
By projecting the original data onto the principal components, PCA provides a compressed and simplified representation, in which data points can be visualized and analyzed more easily. Additionally, PCA can aid in noise reduction and removal of redundancies in the dataset. Moreover, it facilitates the identification of influential variables or dimensions that are crucial in describing the variation within the dataset.
Furthermore, PCA finds application in various fields, such as image processing, pattern recognition, genetics, finance, and many others. It is often an initial step in exploratory data analysis or as a preprocessing step for subsequent machine learning algorithms.