A Comparison of Table and Wall Display

The second study with GROUPGARDEN is designed to compare the wall and the table ver-

sion. The main questions are, whether the location influences self-regulation of the group, whether brainstorming rules are better supported by one of the two display settings and whether it is possible to find out differences between both.

Method

Similar to the first study, the experiment was designed as a laboratory study using a within groups design. Again, two conditions were compared to each other, in this case, the wall and the table version. The same two brainstorming topics were chosen. Again, conditions and topics were counterbalanced.

Setup and Procedure

The main setup and procedure of the study was equal to the first study (see Section 5.1.3). The setup differed only in one aspect. This time, the seating arrangement was predefined. A square table was positioned in the middle of the participants. In the tabletop condition, the group mirror was projected on the table, in the wall version, the table stayed empty (see Figure 5.9). The procedure also differed only in one aspect. In the present study, the group mirror visualizations were explained before each condition, in contrast to the first study, in which no visualization had to be explained before the baseline condition.

Participants

Here too, three participants built one group. None of the participants had taken part in previous GROUPGARDENevaluations. We conducted 8 sessions with 24 participants in total

(11 female; average age: 25 years, range: 20 to 34 years), 18 of them were students, 3

Figure 5.9: Study setup.Left: Tabletop condition. Right: Wall condition.

research assistants, 3 stated other professions. In one group, all group members knew each other before the study, in 12 groups, two of the three group members knew each other and in the other 11 groups, participants did not know each other. Again, participants could choose between a 10AC voucher or credits for their studies.

Results

The captured data (responses from questionnaires on five-point Likert scales and interviews, video data, loggings and notes of the experimenter) were evaluated using the Wilcoxon Signed-Rank Test for Likert scale items and dependent t-tests for all other quantitative data. A 5% level of significance was applied. The statistical software SPSS was used for calculat- ing the Wilcoxon Signed-Rank Test, Excel for calculating t-tests.

Performance Results of the second study do not reveal a significant difference regarding the amount of ideas between the wall condition (M = 37.63, SE= 3.47) and the table con- dition (M = 39,SE = 3.77). This is also supported by the answers of the questionnaires. In the final questionnaire, we asked if participants were more motivated in the table setup. 37% strongly agreed or agreed, 17% were neutral and 46% strongly disagreed or disagreed. In addition, we asked, in which condition participants were more motivated (providing only the two conditions as possible choices). 42% felt more motivated in the table condition, 33% in the wall condition and 25% did not decide and ticked both options. This indetermination is also reflected in some comments from the interviews. So, one participant stated about the table version: “The group was rather more closed and the collaboration was a bit better, but [I was] only a bit more motivated, because I was motivated with both systems.” (G1, P1).

Balance of Participation To evaluate, whether participation was more balanced in one of the two conditions, we classified participants in above average andbelow averagepartici- pants, as in the first study. This time, we took the wall condition as basis. The mean number of ideas in this condition was 12.54, resulting in a categorization of 13above averagepartic- ipants with 13 or more ideas and 11below averageparticipants with 12 or less ideas. Results

5 Supporting Brainstorming

do not reveal any significant differences neither ofabove averageparticipants between the wall condition (M = 15.46, SE = .45) and the table condition (M = 15.77, SE = .83), nor ofbelow averageparticipants between the wall condition (M = 9.09,SE = .5) and the table condition (M= 9.73,SE= 1.45).

Interruptions, Judgments and Deviation from the Topic As in the first study, individual and group warnings had to be used rarely. Individual warnings were displayed seven times, thereof five times in one group. All of these warnings were shown in the table condition. Group warnings were displayed three times, twice in the table and once in the wall condition.

Preferences When asked, which condition participants preferred, 54% stated the table condition and 42% the wall condition (one participant did not have any preference). Reasons that were invoked for the table were that the feedback was better visible (29%), that it was easier to make and hold eye contact (18%), that the group mirror was better integrated in the brainstorming process (13%) and that the feedback on the table enabled better collaboration and communication (13%). One participant stated in the interviews: “It obviously facilitated face-to-face communication, as you have the feedback system and the other group members in your range of vision at the same time. Thus, it was easier for me to hold eye-contact.”

(G1, P1). Reasons stated for choosing the wall condition were that is was perceived as less distracting (25%). Those who sat directly in front of the wall praised the good visibility (8%). Other reasons were that the feedback on the wall produced less pressure than the feedback on the table as it can more easily be ignored (4%). One participant remarked: “There is less pressure on you through the wall feedback. You are more aware of the feedback on the table and a competition arises to overtake the others (...)”(G3, P3).

Seating Position The different seating positions, facing the wall or sitting in a 90 degree angle to the wall, did not expose great differences. The number of ideas, for instance, did not differ significantly. To evaluate this, we compared the person sitting on the left (M= 12.63,

SE= 1.34) with the person on the right (M= 12.5,SE= 1.39). As we did not find any signifi- cant differences, we compared the average number of ideas of these participants (M= 12.56,

SE = 1.33) with the average amount of ideas of the participants seated in the middle and thereof facing the wall (M = 12.75, SE = 1.21). Again, we could not find significant dif- ferences. However, when evaluating the qualitative results, one difference was revealed. People facing the wall emphasized that they “had a better view” (i.a. G8, P2) and could

“more easily take an occasional peek”(G3, P2) on the group mirror.

Summary and Discussion

The second study on GROUPGARDENcompared the initial wall version with a tabletop ver-

sion, with the goal to understand the different affordances and effects of these display envi- ronments on brainstorming.

The quantitative measurable data did not reveal significant differences between the two ver- sions. The number of ideas and the balance of participation seemed to be fairly equal in both conditions. Other rules of brainstorming, not to interrupt each other, not to judge ideas of others and to stay on topic, were observed well in both conditions.

The qualitative results however revealed different advantages of both versions. The wall version was perceived as less disrupting and to produce less pressure. The table version in contrast facilitated eye contact and seemed to be a better suited environment for giving the group a sense of easy communication and collaboration.

Overall, these two studies show that group mirrors can effectively support a creative task such as brainstorming. The placement of the visual feedback can have different effects on how group members perceive collaboration. Dependent on the situation, a wall or a table display may be better suited. For instance, for tasks that need group members to work very focused and concentrated, a wall display could be the better choice as it is perceived as less disrupting. The results, furthermore, indicate that different design decisions can make a difference on how group mirrors are accepted. Due to that, we investigate below the aspects of different concepts of visualizations (more cooperative or more competitive) and another aspect of the display environment (private and shared displays).