In an absolute identification task, participants are asked to recall the labels associated with stimuli that vary on only one dimension. Despite the apparent simplicity of the task, people's performance suggests a severe limit on human capacity for decision making. We have explored the conditions under which this limit can be improved (here). Absolute identification also reveals the human tendency to base responses on previous items and responses. We offer an explanation for such sequential effects here. In follow up work, we are looking at how this model can account for learning, as well as whether it generalizes to human classification and categorization when the stimuli vary on either one or multiple, separable, dimensions.
