We propose a number of concepts and properties related to `weighted' statistical inference where the observed data are classified in accordance with a `value' of a sample string. The motivation comes from the concepts of weighted information and weighted entropy that proved useful in industrial/microeconomic and medical statistics. We focus on applications relevant in hypothesis testing and an analysis of exponential families. Several notions, bounds and asymptotics are established, which generalize their counterparts well-known in standard statistical research. It includes Stein-Sanov theorem, Pinsker's, Bretangnole-Huber and van Trees inequalities and Kullback--Leibler, Bhattacharya, Bregman, Burbea-Rao, Chernoff, Renyi and Tsallis divergences.