Principal Component Analysis (PCA) is widely used for dimensionality reduction but lacks interpretability due to dense linear combinations of features.
A novel sparse PCA algorithm is proposed that imposes sparsity through a smooth L1 penalty and utilizes a Hamiltonian formulation.
Two distinct numerical methods, Proximal Gradient (ISTA) and leapfrog (fourth-order Runge-Kutta), are employed to minimize the energy function.
Experimental evaluations on a face recognition dataset show that the proposed sparse PCA methods achieve higher classification accuracy than conventional PCA.