14. APPENDIX: ON THE MEASUREMENT OF WORKING GROUP GRAPHICS
What kind of measures can be made of vmacs performances, and why would we
want to? Measurement of simple parameters of performance
One promising avenue for future work lies in examing the explicit creation of grouping structures for manipulation which are easy to measure in vmacs. For example, in figure cogAidsTrilogy-cwe might try to find the relation between the manipulative groupings indicated by the tree networks and conceptual groupings (how people see the images together). Now these two kinds of grouping can't be unrelated (unless the operator is trying to trick us), but nor does it seem likely that the relation is one-to-one. Specifying exactly how they are related will take careful research.
But the measures described above only scratch the surface in examining working group graphics; this phenomenon seems to offer fundamental leverage for measuring cognitive behavior. In comparison with protocols taken from a single individual during a cognitive task, working group graphics is explicit, synoptic and graphic. The text-graphics on the group display are explicit and complete in that the group itself monitors to make sure nothing important is left off the display. And at the same time, there is neither room nor time to put up irrelevant material, so the group itself performs synopsis, distilling the salient points from their own verbalizing. In addition, working group graphics uses rich yet easy to process graphic devices of gross texture (line networks, spatial arrangement and juxaposition, variation in text case) to show semantic connections among smaller text-graphic pieces.
However, the cognitive aspects of the current research are still in the fledgling stage, unable to do much with all this leverage. The display of concept development on vmacs may be so rich yet so easy to measure, but the phenomenon of interest seems just out of reach. During the performance, we can see the text-graphics shifting and measure their coursings precisely, so what does that tell us about the coursing of ideas?
Assuming progress can be made on these problems, then in the future perhaps heuristics about text-graphic patternings during concept development can be discovered which could be used by assistive software modules. Under the guidance of such performance-adiminstrators, the group's text-graphic medium might finally become a `rational external device'. A.R. Luria coined this term to describe a card system he designed to help a brain damaged soldier tell a story. The problem was not unlike one often faced by working groups: when telling a story orally, the patient could either generate the pieces or order them, but he couldn't do both. "Replacement of the defective internal schemes by a system of rational external aids provided a practical means of overcoming the patient's defect ..." [Luria66].