  Joint travel decisions, particularly related to social activities remain
poorly explained in traditional behavioral models. A key reason for this is the
lack of empirical data, and the difficulties associated with collecting such
data in the first place. To address this problem, we propose Text-aided Group
Decision-making Process Observation Method (x-GDP), a novel survey methodology
to collect data on joint leisure activities, from all members of a given
clique. Through this method we are able to observe not only the outcome (i.e.,
the joint activity location chosen) but also the decision-making process
itself, including the alternatives that compose the choice set, individual and
clique characteristics that might affect the choice process, as well as the
discussion behind the choice via texts. Observing such a process will allow
researchers to gain a deeper understanding of the joint decision-making
process, including how alternatives are weighted, how members interact with
each other, and finally how joint choices are made. In this paper we introduce
the results of a x-GDP survey implementation focusing on joint eating-out
activities in the Greater Tokyo Area, giving a detailed overview of the survey
components, execution logistics and initial insights on the data. This is to
the best of our knowledge the first attempt to observe group joint travel
decisions in real time through a zoom-moderated experiment.
