Dependency Distance as a Metric of Language Comprehension Difficulty

Linguistic complexity is a measure of the cognitive difficulty of human processing. The present paper proposes dependency distance, in the of dependency grammar, as an insightful metric of complexity. hypotheses are formulated: (1) The human language parser prefers linear that minimize the average dependency distance of the recognized (2) There is a threshold that the average dependency distance of most or texts of human languages does not exceed (3) Grammar and combine to keep dependency distance within the threshold. Twenty from different languages with dependency syntactic annotation are used test these hypotheses. The paper reports the average dependency distance in corpora and analyzes the factors which influence dependency distance. findings — that average dependency distance has a tendency to be in human language and that there is a threshold of less than 3 words average dependency distance and grammar plays an important role in distance —support all three hypotheses, although some questions still open for further research.