ADVANCING THE THEORY OF DSS DESIGN FOR USER CALIBRATION - Human-Computer Interaction and Management Information Systems: Foundations - page 50

that the manner in which dialog symbols are expressed can engender feelings and beliefs. Visibility
refers to dialog symbols and symbols in action (e.g., icons and animation) that facilitate the deci-
sion maker's image of the problem and solution. Inquirability defines both the nature of the act of
inquisition and the acts of discovery and resolution through investigation. Collectively, expressive-
ness, visibility, and inquirability define basic research and development concepts for designing the
symbols and actions of a DSS dialog. Expressiveness, visibility, and inquirability are developed in
more detail below.
Expressiveness
The expressiveness dimension recognizes that the manner or tone in which dialog symbols are
presented can engender feelings and beliefs. The tone of expressiveness can be condescending,
matter-of-fact, supportive, and directive, among others. Expressiveness is currently conveyed to
the user either through presentation or through audio media. In the latter case, expressiveness can
also be monotone and monotonous or melodic and overly melodramatic, each engendering
different feelings in the user.
“One computer system may be capable of sophisticated reasoning but so limited in what
it can . . . express that to a human user it appears to be only the simplest of dialog partners.
Another computer may be severely limited in its reasoning abilities but may give the impres-
sion of considerable intelligence through sophisticated forms of expression. Examples of the
former are expert systems . . . An example of the latter is the ELIZA program . . .” (Edwards
and Mason, 1988, p. 141).
Using the human as a metaphor, it is often difficult for a listener to separate a speaker's dialect
from his or her message and intelligence. One's choice of words and dialect often define the impres-
sion others have of the quality of the message and the speaker's intelligence. Dialog plays a similar
role in DSS, and it is often quite difficult for a user to distinguish the quality of the decision made
using the DSS from his or her impressions about the quality of the DSS themselves.
The expressiveness dimension includes the overall rhetorical strategy for eliciting and pre-
senting symbols. Rhetorical strategy engenders feelings such as “credibility” (Brown and Yule,
1983, p. 148). The expressiveness properties of a DSS dialog can affect one's belief in the quality
of a decision made using the aid. Examples of expressiveness dimensions that may affect user cal-
ibration include framing, connectiveness, and message construction.
Framing refers to the phrasing used to elicit and present dialog symbols. An example of a pos-
itive presentation frame is: “Under these conditions, 95 percent of the time X happens”; the cor-
responding negative presentation frame would be: “Under these conditions, 5 percent of the time
X does not happen.” Even though these convey equivalent information, the latter elicits a different
response from the decision maker than does the former.
In addition to framing, the expressiveness dimension includes connectiveness. Connectiveness
refers to the cohesion of the dialog. Connectiveness includes endophoric reference and resolution.
Two forms of endophoria exist: reference back to material already presented (anaphoric) and ref-
erence forward to material to be presented (cataphoric) (Brown and Yule, 1983, pp. 192-193).
A dialog that exhibits connectiveness engenders credibility because it gives the user the impression
that the DSS are intelligent. In fact, much of ELIZA's ability to engender overconfidence was
attributed to the connectiveness of its dialog (Weizenbaum, 1966).