Βullying is a form of aggressive behaviour that is done intentionally by the bully over a long period of time (sometimes continuing for weeks, months or even years). Victims of bullying have difficulties to defend themselves. Thus, bullying behaviour is seen as an abuse of power and a desire to intimidate). Bullying is not simply an isolated, aggressive action between a "bully" and a "victim". It is rather a dynamic, social relationship problem which is, often, due to hectic human relations involving more participants. It is influenced by peers, families, schools, and communities.
To measure school bullying see Kyriakides, L., Kaloyirou C., & Lindsay G. (2006). An analysis of the revised Olweus bully/victim questionnaire for students using the Rasch measurement model. British Journal of Educational Psychology, 76, 781–801.
To measure school policy and identify priorities for improvement