Artificially structured magnetic superlattices consisting of ultrathin Pd/Co multilayers with varying thicknesses exhibit strong perpendicular magnetic anisotropy. This particular property in such systems is strongly correlated with the structure of the interface and its local environment. In the present work, the interface of Pd/Co in two multilayer systems was sampled applying X-ray photoelectron spectroscopy (XPS) and sophisticated pattern recognition methods for spectrum processing i.e. the k-nearest neighbour rule (kNN) and a clusterization algorithm. For the first time, the fuzzy kNN approach has been applied for investigating surface effects. The above methods consider the lineshape of photoelectron spectra recorded for a set of reference samples, evaluate the criteria for the optimum separation of groups, and identify the unknown samples. Photoelectron Pd 3d and Co 2p spectra were recorded from metallic Pd, Co and CoPd solid solutions with varying concentrations of constituents, and from Pd/Co magnetic multilayers. The applied methods were able to identify the alloying of Pd and Co atoms at the Pd/Co interface of the multilayer systems with different concentrations of component involved. The results obtained indicate that both interfaces have finite thickness, which may influence the magnetic properties of the investigated systems.