Usability Ekspertvurdering

Ekspertvurdering:

• En eksperts vurdering af hjemmesidens brugervenlighed
• Forholdsvis hurtig test
• Middel ressourcekrævende
• Jakob Nielsens 10 heuristikker:
  - Udtryk for brugervenlighed af systemet
  - Udviklet af Jakob Nielsen i 90’erne til software-systemer
  - Middel ressourcer: 4 eksperter
• Test af eksisterende hjemmesider / planlægning

Udførelse:

• 4 eksperter vurderer hjemmesiden hver for sig (1 time)
• Tildeler fejl 1-4 point (4 værst)
• Sætter sig sammen og foretager en samlet vurdering

Ekspertvurdering (Jakob Nielsens 10 heuristikker):

1. Visibility of system status
   The system should always keep users informed about what is going on,
   through appropriate feedback within reasonable time.
2. Match between system and the real world
   The system should speak the users' language, with words, phrases and
   concepts familiar to the user, rather than system-oriented terms. Follow realworld
   conventions, making information appear in a natural and logical order.
3. User control and freedom
   Users often choose system functions by mistake and will need a clearly
   marked "emergency exit" to leave the unwanted state without having to go
   through an extended dialogue. Support undo and redo.
4. Consistency and standards
   Users should not have to wonder whether different words, situations, or
   actions mean the same thing. Follow platform conventions.
5. Error prevention
   Even better than good error messages is a careful design which prevents a
   problem from occurring in the first place. Either eliminate error-prone
   conditions or check for them and present users with a confirmation option
   before they commit to the action.
6. Recognition rather than recall
   Minimize the user's memory load by making objects, actions, and options
   visible. The user should not have to remember information from one part
   of the dialogue to another. Instructions for use of the system should be
   visible or easily retrievable whenever appropriate.
7. Flexibility and efficiency of use
   Accelerators -- unseen by the novice user -- may often speed up the interaction
   for the expert user such that the system can cater to both inexperienced and
   experienced users. Allow users to tailor frequent actions.
8. Aesthetic and minimalist design
   Dialogues should not contain information which is irrelevant or rarely needed.
   Every extra unit of information in a dialogue competes with the relevant units
   of information and diminishes their relative visibility.
9. Help users recognize, diagnose & recover from errors
   Error messages should be expressed in plain language (no codes),
   precisely indicate the problem, and constructively suggest a solution.
   10.Help and documentation
   Even though it is better if the system can be used without documentation,
   it may be necessary to provide help and documentation. Any such information
   should be easy to search, focused on the user's task, list concrete steps to be
   carried out, and not be too large.

Ekspertvurdering:

Ekspertvurdering:
Problemkategorier (kan anvendes til flere tests):
1: Kosmetisk fejl
 Fejl eller mangel, som kun har kosmetisk betydning
2: Mindre fejl
 Fejl eller mangel, som i begrænset omfang kan have effekt på funktion,
 men som ikke påvirker operation eller er årsag til problemer i drift.
3: Alvorlig fejl
 Fejl eller mangel, som har alvorlig effekt på operation eller funktion,
 men ikke blokerer for gennemførelse af operation.
4: Katastrofal fejl
 Fejl eller mangel som bevirker, at en funktion er defekt
 eller en operation ikke kan gennemføres.

Kilde:

Det følgende er lånt fra: http://www.useit.com/papers/heuristic/heuristic_list.html
http://www.useit.com/papers/heuristic/heuristic_evaluation.html
Debbie Stone et al. (2005): User Interface Design and Evaluation (cap. 26), Morgan Kaufmann Publishers, USA