David is a junior in the computer science department at Virginia Tech; he is enrolled in CS3604 Professionalism in Computing. He has extensive experience with computer systems and web-browsing. In order to receive full credit for class participation, he needs to participate in an online debate forum provided on the course web page.The AnalysisThe first goal of David's is to read one of the scenarios available in the online debate. He points his copy of Netscape Navigator on his PC at http://ei.cs.vt.edu/~cs3604. Since it is in the first screenful of the page and in a slightly larger font, he immediately sees the Professionalism Home Pages link and clicks it. This essentially provides a table of contents to David. After scanning five screenfuls of text and links, David finds nothing in the Table of Contents about an online debate, so he clicks the Index of Pages link in hopes of finding the debate. In the first screenful of information, about three quarters of the way down, David clicks the Debates link. Once again, in the first screenful about three quarters of the way down, he sees a line of text stating: "Participants in CS 3604 should start here." He clicks on the start here. The first line of text states "To connect to the Debates click here." He does so. A set of debate choices is presented, in reverse chronological order. Each debate has two choices, Restricted Access and Public Access. He clicks on Public Access for Fall 97 assuming that Restricted Access is for the professor and GTA. He clicks on A: Hacking into a Computer to get Publicly Available Documentation. Here David finds the scenario text along with several links.
David decides to see what classmates have submitted to the debate to get an idea of what kind of submission he needs to make. After the scenario verbiage, David sees a section labelled "Positions." Here arguments are arranged in what appears to be a hierarchy. He clicks the first one, marked with a check and labelled with "Pro position according to the three major types of ethical viewpoints." This hierarchical organization of debate is not how David is used to arguing. He spies the Linearize button and clicks on it in hopes of doing just that, making the debate sound like an argument (one conducted civilly without multiple particpants contributing simultaneously). Now contributions are not presented with the previous abstraction. The full text of all contributions are available at this level, along with their "lineage," that is, what they are in reference to. The system has given a linear ordering to all contributions, such that responses to a contribution are seen immediately after it, in chronological order. Being an explorative user, David tries clicking on the Back to Debate button. He is puzzled by the fact that the browser has taken him two levels back from his current location.
David along the way has seen no mechanism for submitting a comment, the key to his earning a good grade in the class. He clicks the back button and scans each page for artifact. (3 screens) He clicks the Restricted Access link. A preemptive dialog box labelled "Enter Your Name And Password" appears. David recalls the login protocol the professor described in class. He enters his PID and password and clicks OK. He is confronted with a number of debate choices. David returns to the debate he explored previously. David arbitrarily selects the Dave innocent by decree of OS contribution to respond to. He realizes that this contribution is several layers deep into the debate hierarchy from the lineage presented at the top of the screen. He explores the lineage to get up to speed on this particular thread of the debate. David finally returns to the "Dave innocent by decree of OS" contribution. David reads the contribution, and while at the bottom of the page, notices three buttons, Agree, Disagree, and Back to Debate. He clicks on Agree. David is now presented with a simple form where he may enter a subject and argument text. At both the top and bottom of the form, there are Submit and Preview buttons. After David is finished entering his text, he clicks Submit. David now sees his contribution in the manner that others would see it if they selected it for view.
Professionalism Home Pages link from http://ei.cs.vt.edu/~cs3604
The link appears at the top of the page and is in a larger font, so it easy to find.
But users may not realize that the debate is contained in the Professionalism section.
But because of the prominence of this link, the direct connection to the online debate offered farther down the page is obscured. Although from a GOMS standpoint, the expert user would eventually learn this artifact.text and links in the top level Professionalism page
This provides lot of general information and possible tasks to the user.
From a GOMS standpoint, the volume of material will not seriously affect the expert user as that user will ignore extraneous information.
But the debate itself is not provided as an option at this level.Index of Pages off the top level Professionalism page
This is a useful tool for finding specific information regarding the course.
But this is not semantically direct for participating in the online debate.Debates link on the Professionalism Index of Pages
This is displayed in the first screenful of text, so it is again easy to find.
But the user might think this is commentary or information on the debate tool itself.start here link to enter online debate
This information is semantically direct.
But the fact that the text states this suggests that the results of this action are not otherwise intuitive.click here link to enter online debate
This information is semantically direct.
But the fact that the text states this suggests that the results of this action are not otherwise intuitive.
But if we look at an extension to the GOMS model and forego the assumption that we are dealing with an expert user that would know of the link off of the top level CS3604 page, we have now cost considerable time by going through four extra pages.debate choices is presented at the top level of the online debate tool
Past semesters are available for view to provide examples.
The fact that it is in reverse chronological order makes the current choice the first.Restricted Access and Public Access options for each semester's online debate
Allows additional user classes to be involved in the debate. (i.e. the non student)
With respect to TAG, this symmetry in commands is desirable.
But users may not realize which path is correct.A: Hacking into a Computer to get Publicly Available Documentation debate
A set of debates is available at this level.
But users may not realize each link is a separate debate.arguments are arranged in what appears to be a hierarchy inside this particular debate
The hierarchical choice for display facilitates comprehending the nature of the debate.
But arguments are carried out in a linear fashion, not a web-like one.first one, marked with a check - first contribution to this particular debate
Provides direct manipulation. Clicking on the argument subject reveals its text.
Arguments are tagged with a check or an "x." This forces users to take issue with the point they are commenting on. It also allows users reading the arguments to determine how arguments are oriented without delving into the text of each one individually.
But there is no feed forward to denote that clicking will reveal the text.
But users may perceive the check and "x" scheme to reflect the quality of the argument.
But with the many levels in the hierarchy of arguments, the meaning of the check or the "x" may be lost (e.g. an agreement with a disagreement) This problem is aggravated with the linearize feature mentioned elsewhere.Linearize the contributions to the debate
Provides a mechanism for viewing the contributions in a linear fashion (which is how civil individuals argue).
This artifact provides the user a metaphor for how a real world debate would occur.
But there is no de-linearize artifact.
But the linearize button is still visible after the debate has been linearized, suggesting that this goal has not been achieved.
But TAG would suggest that there be a symmetrical method to "delinearize" the debate.contributions after using the Linearize artifact
In this state, the contributions are not abbreviated by subject; their full text is forced upon the user.
The lineage feature in this state still provides the "history" information.
But, the loss of abstraction may overwhelm readers since there are now pages and pages of information to sift through with no indexing mechanism.
But, that history infomration was more intuitively obvious in the non-linearized format.Back to Debate artifact in the online debate
Provides a mechanism independent of the browser provisions for "backing up."
With respect to the GOMS model, backing up to the top level of the online debate tool is helpful for the expert user who wishes to complete this task rather than just backing up one page.
But this artifact is inconsistent with the meaning of "back" in the browser button. The browser button will only take the user back one screen, this button takes the user back to the top level of the debate.artifact - the nonexistant artifact to login
Since the user is currently in a "restricted" state, this provides security for the debate by forcing arguments to be associated with a registered user.
But users that can legitamitely make additions must back out of the system to make their submission.
But from a GOMS standpoint, this is unnecessary overhead, since the user now has to perform additional actions that would be eliminated by such an artifact.preemptive dialog box labelled "Enter Your Name And Pasword" for login task
Dialog boxes mean screen space is only consumed when necessary.
But preemptive dialog boxes force the user to complete a task before continuing towards the goal.Agree and Disagree buttons presented when reading a contribution to online debate
Force the user to take issue with the comment at hand. This in itself should spark additional discussion.
This symmetry in commands and artifact verbiage is good in the eyes of TAG.
But, a user may indeed have a valid comment to make that is independent of agreeing or disagreeing with the issue.simple form to contribute to the online debate
Provides a simple means to submit a contribution to the debate.
Although this may now be taken for granted, the display editor method is highly prefereable over the line editor.
But with respect to direct manipulation, this is removing the user from the original object of concern, i.e. the specific contribution. The text of the specific contribution is not available at the time of entering one's own contribution.Submit and Preview buttons presented when entering a contribution to the debate
The Preview artifact provides a means for users to see the consequences of their action before actually committing to it.
The Submit artifact allows the more confident user to bypass this step.
But users selecting Preview may not realize that they have to go back and submit in order to finalize their transaction with the debate.