This paper introduces a principal component analysis (_-PCA) in a topological structure called _-linear spaces. The _-PCA consists in an isomorphic deformation of the usual PCA through a hyperparameter. It is shown that the statistics employed in standard PCA (cosines and correlations) exist in _-linear spaces, these are U-statistics. As the regular PCA is a special case of _-PCA when = 1, simulations and applications on images are provided to outline the relevance of the _-PCA in various settings and specifically in the presence of noise and outliers.
Mussard et al. (Sun,) studied this question.