比較による知識の分散：可視化形式と比較戦略がタスクパフォーマンスに与える影響

Teams can benefit from collaboration tools that make distributed knowledge more accessible and comparable when sharing and integrating information. Comparative knowledge visualizations serve this function by presenting multiple knowledge profiles within a shared display. This allows users to distinguish shared information from unshared information. Despite the widespread use of knowledge visualizations in collaborative settings, comparatively little is known about how specific design choices support comparing multiple knowledge profiles. This study examined how comparative knowledge visualizations support users' understanding of distributed knowledge. The study focused on two core design decisions: how to represent conceptual knowledge and how to arrange multiple profiles within a shared display.

We manipulated two core design decisions in comparative knowledge visualizations, each of which was implemented in two variants: knowledge representation format (concept maps versus proposition lists) and visual comparison strategy (juxtaposition versus superimposition). We also varied task complexity to test whether design advantages increase as comparison demands rise. In a 2 × 2 × 3 mixed-design experiment (N = 133), participants completed a visual comparison task in which they judged whether statements about the distribution of knowledge across three fictional group members were true or false based on the visualization. We assessed accuracy, response time, and perceived cognitive usability.

Comparison strategy showed a robust effect: superimposition yielded faster responses overall and higher accuracy under medium and high complexity. Knowledge format did not affect performance. Usability ratings indicated complementary advantages: superimposition was perceived as more helpful for comparing profiles and accessing group-level knowledge, whereas juxtaposition was rated clearer and more supportive for identifying individual knowledge.

The effectiveness of comparative knowledge visualizations depends on how multiple profiles are perceptually aligned and separated to match the epistemic goal (integrative comparison vs. source-specific inspection) and the processing demands of the task. The results provide evidence-based guidance for designing comparative displays that support identification of shared and unshared knowledge in collaborative work.