Animal farming emissions from pig and broiler chicken livestock activities were analyzed by means of selected ion flow tube mass spectrometry (SIFT-MS) using full mass scans in the m/z range 15–250 with H3O+, NO+ and O2+ as precursor ions. The generated set of data was used to investigate the similarity between samples using raw experimental SIFT-MS data by means of similarity coefficients, which was the main goal of this paper. The so-called ‘Yule coefficient’ is chosen as the best tool to identify the similarity between samples. The proposed methodology is successfully applied on an artificially constructed data set as well as on data from different experimental sampling campaigns. From an engineering point of view, it is considered to be a promising technique to evaluate whether a sample corresponds to one of the catalogued library data sets.