Karsenty, Laurent2017-04-152017-04-151997978-94-015-7372-6If the sharing of context is now widely acknowledged as a condition for successful communication, existing studies do not allow to determine whether it is necessary to restore the maximum of shared information to obtain the best communicative performance. To address this issue, three help dialogue conditions distinguished by the amount of shared information, are compared. The analyses are focused on the comprehension problems raised by each condition. The results highlight that the quality of a help dialogue is not necessarily linked to the quantity of shared information. They also exhibit that the inability to share some specific information strongly affects communication efficiency. Implications for the design of computer-mediated communication systems are drawn from these resultsenText