A structured method for the traffic dispatcher error behavior analysis in metro accident investigation

Identifying the traffic dispatcher error behaviors that frequently result in the occurrence of metro accidents is beneficial to prevent error behaviors and mitigate their consequences. Yet, there is no theoretical framework available for metro safety officers in investigating and classifying traffic dispatcher error behaviors. This article presents a structured procedure to analyze traffic dispatcher error behaviors in emergency based on the human information processing theory and the modified task analysis framework. In order to make the proposed method be more applicable to practical use, a detailed task list of traffic dispatcher in case of emergency is given by considering the characteristic of equipment in operation control center (OCC) to simplify the task analysis procedure. And the traffic dispatcher error behavior classification with an error degree value scale derived from the VACP model is built to identify the error behavior type, which defined human behaviors according to the information processing stages. Finally, the validation and reliability studies have been carried out to assess the reasonability of the proposed method. The grey relational analysis (GRA) of the data from 98 traffic dispatcher error related accident reports indicates an acceptable validation of the proposed error behavior classification. And the reliability analysis suggests an adequate inter-coder consensus of more than 70% percentage agreement of the proposed method in practical use.