Joint change-detection: how the interplay between scene context and object detection is affected by task setting

Akkuşcu, Mustafa
In this paper, we study the effects of social setting on change-detection performance: First, we investigate how detection of changing (i.e., repeatedly appearing and disappearing) objects in scene images is influenced by the scene context. If a changing object’s identity is in conflict with its surrounding context (e.g. a boat on a highway), that is a semanticallyinconsistent change; if there is no such conflict (e.g., a boat in a lake), that is a semantically-consistent change. We found, in line with previous studies in the literature, that inconsistent changes were detected more often (more accurately) and faster than the consistent ones, probably because attention was attracted towards inconsistent objects earlier than the consistent ones. Second, we investigate how joint-action settings (i.e., cooperative and competitive) affect performance on the change-detection task. Based on social facilitation literature, which indicates simple tasks are performed better and complex tasks are performed worse in the presence of others, we expect that detecting inconsistent changes (a simple task) are even more often and faster, whereas detecting consistent changes (a complex task) are even less often and more slowly in the presence of a cooperating or competing co-actor, as compared to individual condition. However, we did not find such a differential effect. Instead, our results showed that cooperating subjects performed similarly to the individual subjects; competing subjects, though detected the inconsistent changes more often than the consistent ones, were less accurate but faster on both types of change relative to the individual subjects. 


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Citation Formats
M. Akkuşcu, “Joint change-detection: how the interplay between scene context and object detection is affected by task setting,” M.S. - Master of Science, Middle East Technical University, 2017.