The possibility that "coder drift" may be a source of bias in classroom observation systems was investigated in two parallel experiments using the Flanders System of Interaction Analysis. Coder drift may be described as the differences in coding which result when observers create their own idiosyncratic systems of classifying teacher…

The results of two experiments support the hypothesis of "coder drift" which is defined as change that takes place while trained coders are using a system for a number of classroom observation sessions. The coding system used was a modification of the low-inference Flanders System of Interaction Analysis which calls for assigning…

Two predictors of coding performance were validated when 26 trained subjects used the Flanders System of Interaction Analysis to code 11 half-hour videotapes of fifth grade classrooms. The Teacher Evaluation Scale, a high-inference rating system based on the Global Rating Scales, was also used. The predictors were scores on a shortened form of the…

As part of an ongoing investigation of the relationship between teacher behavior and pupil affective and cognitive outcomes, coders practiced recording their observations of existing classroom videotapes in order to determine the amount of interobserver agreement. The videotapes were coded, using seven existing low- to medium-inference classroom…