ABSTRACT
A crucial concern in research is the interdependence between an act of measuring and the data the measure produces. In other words, it is important that we avoid influencing a phenomenon while it is being measured. For example, a method that requires a participant to interact with the experimenter, or questionnaire material, may be more susceptible to these extraneous effects than one based on passive measurement, such as that afforded by embedded metrics. Many researchers have questioned the utility of interruption-based measures of situation awareness (SA) in terms of both the necessity for interrupting the simulation and the possibility of reorienting the participant (and therefore the task) to future SA probes. To this end, McKenna and Crick's (1994) driving hazard perception test was adapted to measure S A using embedded measures of anticipation alongside interruption-based SA probes. The interruption-based measures were manipulated so that the effects of task interruption could be differentiated from the effects of task reorientation in terms of their effects on the embedded measures of anticipation.
