Rzayev, RufatKaraman, GürkanWolf, KatrinHenze, NielsSchwind, ValentinAlt, FlorianBulling, AndreasDöring, Tanja2019-08-222019-08-222019https://dl.gi.de/handle/20.500.12116/24602Virtual reality (VR) enables users to experience informal learning activities, such as visiting museum exhibitions or attending tours independent of their physical locations. Consequently, VR offers compelling use cases by making informal learning and education accessible to a broader audience and simultaneously reducing the carbon footprint. For many learning activities, the presence of a human guide is essential for participants' experience. The effect of the presence of a guide and its appearance in VR is, however, unclear. In this paper, we compare a real-world guide with a realistic, an abstract, and an audio-only representation of a virtual guide. Participants followed four multimodal presentations while we investigated the effect on comprehension, presence, co-presence and the perception of the guide. Our results show that even a realistic presentation of a guide results in significantly lower co-presence, humanness, and attractiveness compared to a human guide. Qualitative results and participants' feedback indicate that having no visual representation of the guide helps to focus on the content but can reduce the connection with the guide.enVirtual realityVirtual avatarPresenceCo-PresenceUncanny valley effectText/Conference Paper10.1145/3340764.3340802