1. April 19, 2004“Design of User-Friendly Systems” DLC, 2004 1 The Psychology of Everyday Actions “Humans will try to figure it out” A user sits down at an interface with a goal. The user… 1) Observes what functionality is available. 2) Forms a conceptual model of how the system works. 3) Takes an action to achieve the goal. 4) Observes the outcome of the action, was it right or wrong? 5) Either Reinforces or Discredits his conceptual model. 6) Continues until the goal is accomplished.

2. April 19, 2004“Design of User-Friendly Systems” DLC, 2004 2 The Psychology of Everyday Actions This is good if ??? - The interface understands how the user approaches the system. - Allows the user to explore the system risk free. - Provides only necessary functionality at the top level. - Handles Errors. This is bad if ??? - Inappropriate actions result in no or incorrect feedback. - There is no forgiveness for mistakes. - The model of the system varies from the conceptual model of the user.

3. April 19, 2004“Design of User-Friendly Systems” DLC, 2004 3 The Psychology of Everyday Actions A good system understands how users get lost…. - Can the user build a conceptual model of the system from the interface? (false models, misconceptions) - Does the feedback of actions discredit the model? (Falsely Blaming yourself, Blaming the wrong cause) - Does the system reinforce misconceptions? (Learned Helplessness, Taught Helplessness)

4. April 19, 2004“Design of User-Friendly Systems” DLC, 2004 4 The Psychology of Everyday Actions A good example: Delete Confirmation - Confirmation that an action was taken. - A correlation of the action and observation. - A way out of a dangerous situation. A bad example: MS Word Auto Format - no relationship between action and outcome. - no consistency between the outcomes. - not always possible to reverse action and get back to where we started.

5. April 19, 2004“Design of User-Friendly Systems” DLC, 2004 5 The Psychology of Everyday Actions -Design Aids to Compliment the User’s Thought Process… 1) Visibility The user will see what is available and act accordingly. 2) A Good Conceptual Model The user will form a simple model, does the system allow models to be formed? 3) Good Mapping Is there a correlation between the action and the outcome? 4) Feedback Users reinforce/discredit their model according to the reaction they get from an action. If there is no action, the user is lost.

6. April 19, 2004“Design of User-Friendly Systems” DLC, 2004 6 Knowledge in the Head and In the World “Digital Media Offers Overwhelming Information” 1)There is too much information for the user to remember. 2)Designers must Decide which information will be memorized and which will be stored in the system.

7. April 19, 2004“Design of User-Friendly Systems” DLC, 2004 7 Knowledge in the Head and In the World What are the Tradeoff ??? Knowledge in the WorldKnowledge in the Head Retrievability:Available when visible/audibleRequires Memory Search Learning:Not RequiredRequired Efficiency:SlowFast once Retrieved First Encounter:EasyDifficult

8. April 19, 2004“Design of User-Friendly Systems” DLC, 2004 8 Knowledge in the Head and In the World What do we do ??? - Exploit the Nature of Human Thought - Humans want to form a “conceptual model” of all things. - Information without a model is difficult to remember. - Try to communicate Concepts instead of Raw Information Ex)1) Where do you find the information vs. What is the information? 2) How Features Alter the System vs. What Specifically do the features do?

9. April 19, 2004“Design of User-Friendly Systems” DLC, 2004 9 Knowledge in the Head and In the World Mappings Can Help “Knowledge in the World” “Stove Control Example” No Mapping Natural Mapping This exploits the human need for a conceptual model through “mappings”

10. April 19, 2004“Design of User-Friendly Systems” DLC, 2004 10 Knowledge in the Head and In the World Understanding Memory Can Help “Knowledge in the Head” 1) Memory for Arbitrary Things (difficult, standardization helps) 2) Memory for Meaningful Relationships (efficient) 3) Memory through Explanation (conceptual models)