Determinerless PPs are prepositional phrases that allow singular count nouns to occur without a determiner, despite other rules in the grammar requiring its presence. In a wide variety of languages, this rule seems to be weakened, as e.g. in ohne mündliche Vorwarnung, (‘without verbal warnings’), or unter sanfter Androhung (‘under gentle threat’). From a grammatical perspective, among manifold manifestations especially those combinations are worth investigating that exhibit four properties: the noun in the combination must be countable, determiner omission must only be possible if the phrase is embedded under a PP, the omission is optional and the combination must have phrasal status. In the course of the project, we have developed an analysis that is based on annotated corpus data, which are fed into a statistical classifier (applying logistic regression). Superficially, the syntax of bare prepositional phrase is erratic, and intuitions cannot be easily elicited. The results of the classifiers applied to annotated data indicate which syntactic, morphological and semantic features are responsible for determiner omission. We have thus been able to detect common properties of groups of prepositions, as well as preposition-specific, and idiosyncratic properties. The apparently erratic conditions for determiner omission can be discerned by tracing the interaction of these properties.