The (SPC) method was proposed for statistics regression problems where the number of variables greatly exceeds the number of samples. A recent article in Journal of Chemometrics  describes this interesting approach and compares it with commonly used ones.
- J. Bin, F. Ai, N. Liu, Z. Zhang, Y. Liang, R. Shu, and K. Yang, "Supervised principal components: a new method for multivariate spectral analysis", Journal of Chemometrics, vol. 27, pp. 457-465, 2013. http://dx.doi.org/10.1002/cem.2558