General criteria for including items in the User Contexts profile

Note: this is not my action item from the meeting, but it elaborates my
suggestion to propose general criteria for including items in the user
needs/preferences profile supported by User Contexts.

this is very preliminary and exploratory; improvements and clarifications are
welcome.

Proposal:

An item is a candidate for inclusion in the User Contexts specification if it
satisfies the following:

1. It is expressible as a variable, with well-defined values, that reflects a
need or preference of the user.

2. Different values of the variable are needed or preferred by different
users, or by the same users under different and readily distinguishable
circumstances.

3. Consider a Web application, i.e., an application implemented by standard
client-side and server-side Web technologies. To different values of the
variable, there are corresponding differences that can occur in the user
interface. These differences are under the control of, or can be significantly
influenced by the Web application. For example, differences in a font size
preference should be reflected in different fonts presented to the user, and
these differences can be influenced by the Web application in that it can set
appropriate CSS font properties. However, in the absence of a standardized
speech API, speech synthesizer properties (pitch, speech rate etc.) cannot be
controlled or significantly influenced by a Web application and thus would not
be candidates for inclusion. (Note: this isn't a good example due to the
existence of aural CSS - a better illustration of the point is needed.)

The differences in the application's user interface which are dependent on the
value of the variable may affect presentation, behaviour or a combination of
both. Although it is not the purpose of the specification to constrain how
application developers can adapt their user interfaces to reflect the user's
expressed needs and preferences, this criterion requires the types of
differences involved to be clearly understood. Elements of the need/preference
profile should be specified so as to make the effects on the user interface as
obvious as possible to potential implementors. For example, a "minimize the
number of user interface controls presented simultaneously" preference is
clearer and more specific than a "present a simple user interface" preference,
and thus the former is better specified.

4. The differences in the user interface as provided by a Web application
depending on the value of the variable, make the application significantly
more accessible or more efficient to use by people who need or prefer a
particular value of the variable. For example, a variable for font size, which
is to be applied in applications by varying the actual font size of text, can
make the user interface accessible to people who are vision-impaired, or
significantly improve its readability under circumstances in which small fonts
are difficult to perceive.

5... Further requirements to be added as they come to mind.

Received on Wednesday, 18 September 2013 23:32:04 UTC