Loading ...
Sorry, an error occurred while loading the content.

1073RE: [agile-usability] Re: Re: Task model => User Interface ... Through task (esential use) cases?

Expand Messages
  • Larry Constantine
    Feb 24, 2005
    • 0 Attachment

      Of course, there is no simple algorithmic test, but here is how I view it.
      An essential use case is "ready" when four things are true.

      (1) It is expressed at an approprate level of abstraction. It is abstract
      and generalized but still specific to the particular task case and the
      application being designed. In other words, it is not "unsuitably vague."
      ("Expressing needs" as a user intention is unsuitably vague; "specifying
      kinds of entertainment is of interest" is not.)

      (2) It is technology- and implementation-independent. It has been purged of
      all technological or implementation terms and of all references, explicit or
      implicit, to specific solutions. This includes hidden assumptions in such
      technology-oriented words as "list" (implies a list of items). Seemingly
      innocent common words like "search" often carry implied baggage. (A user may
      intend to "find" or "get" or "identify" something, but "search" is a
      specific technology solution, not a user intention. The moment you use the
      word, it becomes all but impossible not to visualize a search box with a
      "go" button.)

      (3) It is expressed in terms of ordinary user language and the defined
      vocabulary of the subject matter or application domain. Elements of the
      subject matter or application domain are correctly and consistently

      (4) It is complete, enabling the user to perform the overall intention it
      represents. We verify completeness by walking through the task case, asking
      whether the user could complete the task assuming a user interface that
      supplied the necessary features and a system that carried out its

      With regards to the last criterion, completeness may refer only to the
      "happy case" or also to exceptions and alternatives, depending on resources
      and level of formality of the process. If it is a small application being
      designed under agile conditions, extensions may be allowed to emerge as
      needed rather than being elaborated and validated explicitly at the outset.

      --Larry Constantine, IDSA [mailto:lconstantine@...]
        Chief Scientist | Constantine & Lockwood, Ltd. | www.foruse.com

      > -----Original Message-----
      > From: news [mailto:news@...] On Behalf Of Agustín Villena
      > Sent: Thursday, 24 February 2005 1:58 PM
      > To: agile-usability@yahoogroups.com
      > Subject: [agile-usability] Re: Re: Task model => User Interface ...
      Through task (esential use)
      > cases?
      > Hi Larry!
      > The problem that I faced when trying to apply U-CD (in the Larry way) is
      > that Is really dificult to know when the esential use case is "ready".
      > Thnking "a la" Test Driven Development: what tests the essential use case
      > should pass to be considered "ok"?
      > Agustin
    • Show all 10 messages in this topic