Pritchard W S
Brain Res Bull. 1984 Sep;13(3):465-73. doi: 10.1016/0361-9230(84)90099-6.
A portable laboratory computer program for performing varimax-rotated principal components analysis (PCA) of event-related potentials (ERPs) is described. The program is written in FORTRAN 77; its compiled version requires 429, 140 bytes of memory. The program reads a matrix of numbers from an input file. The PCA can be performed on either the variance/covariance or the correlation matrix. The program computes the first six principal components. The user is given the option of rotating as many of the principal components as desired based upon the percentages of variance that they account for. Eigenvalues, percentages of variance, cumulative percentages of variance, factor loadings, and factor scores are written to an output file. Description of the program is preceded by a conceptual overview both of PCA as a factor analytic technique and of the application of PCA to ERP data analysis.
本文介绍了一种用于对事件相关电位（ERP）进行方差最大化旋转主成分分析（PCA）的便携式实验室计算机程序。该程序用FORTRAN 77编写；其编译版本需要429,140字节的内存。该程序从输入文件中读取一个数字矩阵。PCA可以在方差/协方差矩阵或相关矩阵上进行。该程序计算前六个主成分。用户可以根据主成分所解释的方差百分比选择对任意数量的主成分进行旋转。特征值、方差百分比、方差累积百分比、因子载荷和因子得分被写入输出文件。在程序描述之前，先对作为一种因子分析技术的PCA以及PCA在ERP数据分析中的应用进行概念性概述。
