An increasing attention is being devoted by many scholars to the phenomenon of the collaborations between university and other research institutions with industry. The new knowledge arising from such collaborations is often disclosed trough the scientific publications and the creation of new knowledge is rarely a solitary activity; knowledge creation and innovative activities usually take place within networks and come out from collaborations. Notwithstanding this increasing attention, some aspects of such collaborations remain probably not enough investigated. In particular there is need of a thorough analysis about the relationship between the activities and characteristics of the firms on one side and the frequency of the collaborations ...