GIS III

                                                 interpretant (meaning)

       < perception, social processes >                  <cognition, mental processes>

sign vehicle (symbol)          < design process, generalisation >           referent (reality)

• evaluation of human visual processing of visual marks on a map
• Determination of visual limits, color issues
• Concerned with: immediate user response, external processes, observable behaviour
• Understanding dichotomy (Zwiespalt) between:
  map maker attempts to encode information
  map user decodes information
  physical limitations of visual systems

• Evaluation of human mental processing of map information that eventually leads to overt behaviour
• Concerned with: Longer-term behaviour, internal processes, non-observable behaviour

-->  How do people understand and acquire knowledge from maps

Graphic display designed such that it matches human’s internal visualization capabilities well

cognitively plausible graphic display that is able to augment people’s mental visualization capabilities for complex reasoning and problem solving in abstract domains.

• Develop new interaction methods (or even paradigms)

• Evaluate with user studies

  --> Usability Evaluation

• Extract general design rules

- Adapt known design rules

- Systematically integrate uability in the software development process --> Usability Engineering

- Evaluate usability of real systems --> Usability Evaluation

“the extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of user»

1. Effectiveness: achieve specific goal accurately and completely
2. Efficiency: as little work and time as possible
3. Learnability: easy to learn (also for infrequent users)
4. Satisfaction
5. Error-tolerancy

1. Use knowledge in the world and in the head
2. Simplify the structure of tasks
3. Make things visible
4. Get the cognitive mapping right
5. Exploit constraints
6. Design for error
7. Standardise

1. Know the user
2. Competitive (wettbewerbsfähig) analysis
3. Setting usability goals
4. Parallel design
5. Participatory design
6. Coordinated design of the total interface
7. Apply guidelines and heuristic analysis
8. Prototyping
9. Empirical testing
10. Iterative design
11. Collect feedback from field use

• Formative evaluation: Iterative process throughout development
• Summative evaluation: only end product
• Quick and dirty: Fast feedback, prototyping
• Longitudinal studies: over longer time
• Case study: intensive study of a single unit à generalisation
• Remote study: experimenter and subject not at same place
• Participatory design
• Convergent method paradigm: several of these frameworks

• Questionnaires
• Interviewing
• Verbal protocol analysis: User verbalises thoughts during interaction
• Onscreen interaction capture
• diary keeping
• Eye tracking
• Brain activity
• Other physiological sensors

• Content analysis (qualitative data)
• Statistical analysis
• Severity rating
• Problem frequency counting
• performance measures
• subjective measures

situational context

personel context

- funcitonal requirements: protocol, service, data

- non-functional requirements: reliability, availability, robustness, security

- Client-server

- 3-tier (presentation, application logic, data)

- multi-tier

- Spatial Data

- Services

- Presentation

Atomicity

Consistency

Isolation

Durability

Basically Available

Soft-state

Eventually consistent

Representation State Transfer

- DTD (Document Type Definition) and XML Schemas

- CSS

- XSLT & XPath

- DOM, SAX, JAXP --> XML APIs for XML parsing

- elements

- tags

- attributes

- entitles

- character data

Java Script Object Notation

Remote Procedure Call

Simple Object Access Protocol

Representational State Transfer

• Availability and Access
• Reuse (Wiederverwertung) and Redistibution
• Universal Participation: everyone use and redistribute

• complete (available and not subject to privacy restrictions)
• primary (unprocessed)
• timely (up-to-date)
• accessible
• machine-processable
• open to anyone
• non-proprietary (ungewerblich) formats
• license-free
• permanence (able to be found at any time)
• cost (no more than minimal)