Solar eruptions, such as solar flares (SFs) and coronal mass ejections (CMEs) are the primary drivers of space radiation storms. A key element for the decoding of such storms is the establishment of empirical statistical relations between their characteristics and the observed properties of their parent solar events. These attempt to unfold patterns and relationships, using all observational evidence at hand, which in turn point to the underlying physical processes of the generation of space radiation storms. We report on new data driven statistical methods that have been developed for the identification of the likelihood of Solar Energetic Particle (SEP) event occurrence and their expected characteristics. These methods are based on precursor information of SFs [forecasting mode] and on actual data of SFs, CMEs and radio bursts [nowcasting mode]. A reductive statistical method for the SEP probability of occurrence has been implemented, using as input SF information. It makes use of, either, the expected full disk probability [forecasting mode] or of the location (longitude) and the size (maximum soft X-ray [SXR] intensity) of the flare [nowcasting mode]. Moreover, employing CME parameters (velocity and angular width), proper functions perwidth (i.e. halo, partial halo, non-halo) have been identified. We demonstrate the validation of each method using categorical scores constructed on archived data and we further present independent case studies.