Four different observational systems and two time sequences were employed to determine the extent to which they would yield different incidences of anti-social behavior. Two videotapes, randomly chosen from a pool of 30 tapes, were utilized. These illustrated the behaviors of anti-social children in a natural setting. Six observers were reliably trained in the observational systems. Observers, systems, time sequences, and tapes were assigned randomly and counter-balanced, thus providing for a within experimental replication. The results of the experiment indicate no significant differences for time sequences or observational systems. The results are discussed briefly in terms of their significance for time sampling methods used in behavioral analyses. (Author)