Analysis of English free association network reveals mechanisms of efficient solution of the Remote Association Tests

In this paper we study the connection between the structure and properties of the so-called free association network of the English language, and the solution of psycholiguistical Remote Association Tests (RATs). We show that average hardness of individual RATs is largely determined by the relative positions of the test words (stimuli and response) on the free association network. We argue that solution of RATs can be interpreted as a first passage search problem on a free association network and study a variety of different search algorithms. We demonstate that in easy RATs (those solved by more than 64% subjects in 15 seconds) there are strong links directly connecting stimuli and response, and thus an efficient strategy consist in activating these direct links. In turn, the most efficient mechanism of solving medium and hard RATs consists of preferentially following what we call "moderately weak" associations.