Lecture 6
Requirements and Models
Human Computer Interaction/COG3103, 2016 Fall Class hours : Monday 1-3 pm/Wendseday 2-3 pm Lecture room : Widang Hall 209 10th October
Exercise 4-1: Flow Model Sketch for Your System
• Goal
– Get practice in making an initial flow model sketch for the work practice of an organization.
• Activities:
– For your target system sketch out a flow model diagram, in the same style as our flow model sketch for MUTTS, shown in
Figure 4-3, showing work roles, information flow, information repositories, transactions, etc.
– Draw on your raw work activity data and construct a representation of the flow of data, information, and work artifacts.
Even if there is no existing automated system, you should capture the flow of the manual work process.
– Start with representing your work roles as nodes, add in any other nodes for databases and so on.
– Label communication and flow lines.
– If you do not have enough contextual data from your limited data-gathering exercise, make some up to make this work.
• Deliverables
– A one-page diagram illustrating a high-level flow model for the existing work process of your target system.
• Schedule
– Given the simplicity of the domain, we expect this exercise to take about an hour.
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ORGANIZING CONCEPTS: WORK ROLES AND FLOW MODEL
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Figure 4-3 An initial flow model sketch of the MUTTS system.
Homework
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Finish the Class Exercise 3-1
Complete Flow Model Sketch for
Your System
Finish the Class Exercise 4-1
1 2 3
Your Blog Post #5 - 150 words or fewer
Iterate your concept and flow models - Upload sketches and diagrams
on your pinterest boards - Boards can be divided into a
few such as - Users/Actors - Entities - Context - Benchmark system cases - flow diagrams
Your Blog Post #6 - A one-page Diagram - 5 Benchmark Cases You
may wish to refer
EXTRACTING INTERACTION DESIGN REQUIREMENTS
Textbook Chapter 5.
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INTRODUCTION
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Figure 5-1 You are here; the chapter on extracting interaction requirements, within understanding user work and needs in the context of the overall Wheel lifecycle template.
INTRODUCTION
• Gap between Analysis and Design
– Information coming from contextual studies describes the work domain
but does not directly meet the information needs in design.
– There is a cognitive shift between analysis-oriented thinking on one side
of the gap and design-oriented thinking on the other.
– The gap is the demarcation between the old and the new—between
studying existing work practice and existing systems and envisioning a
new work space and new system design space.
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INTRODUCTION
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Figure 5-2 Overview of the bridge to design.
NEEDS AND REQUIREMENTS: FIRST SPAN OF THE BRIDGE
• What Are “Requirements”?
• Requirements “Specifications”
– Detailed formal requirements cannot ever be complete.
– Detailed formal requirements cannot ever be 100% correct.
– Detailed formal requirements cannot be prevented from changing
throughout the lifecycle.
• Software and Functional Implications of Interaction Design
Requirements
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FORMAL REQUIREMENTS EXTRACTION
• Walking the WAAD for Needs and Requirements
• Switching from Inductive to Deductive Reasoning
• Preparation
• Systematic Deduction of Needs as “Hinges” to Get at Requirements
• Terminology Consistency
• Requirement Statements
• Requirement Statement Structure
• Requirements Document Structure
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FORMAL REQUIREMENTS EXTRACTION
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Name of major feature or category Name of second-level feature or category Requirement statement [WAAD source node ID] Rationale (if useful): Rationale statement Note (optional): Commentary about this requirement
Security Privacy of ticket–buyer transactions Shall protect security and privacy of ticket-buyer transactions [C19] Note: In design, consider timeout feature to clear screen between customers.
Figure 5-3 Generic structure of a requirement statement.
Figure 5-4 Example requirement statement.
FORMAL REQUIREMENTS EXTRACTION
• Continue the Process for the Whole WAAD
• Keep an Eye out for Emotional Impact Requirements and Other Ways
to Enhance the Overall User Experience
• Extrapolation Requirements: Generalization of Contextual Data
• Other Possible Outputs from the Requirements Extraction Process
– Questions about missing data
– System support needs
– Marketing inputs
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FORMAL REQUIREMENTS EXTRACTION
• Constraints as Requirements
• Prioritizing Requirements
• Taking Requirements Back to Customers and Users for Validation
• Resolve Organizational, Sociological, and Personal Issues with the
Customer
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ABRIDGED METHODS FOR REQUIREMENTS EXTRACTION
• Use the WAAD Directly as a Requirements Representation
• Anticipating Needs and Requirements in Contextual Analysis
• Use Work Activity Notes as Requirements (Eliminate the WAAD
Completely)
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CONSTRUCTING DESIGN-INFORMING MODELS
Textbook Chapter 6.
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INTRODUCTION
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Figure 6-1 You are here; the chapter on constructing design informing models, within understanding user work and needs in the context of the overall Wheel lifecycle template.
DESIGN-INFORMING MODELS: SECOND SPAN OF THE BRIDGE
• What Are Design-Informing Models and How Are They Used?
– help integrate and summarize the contextual data
– point back to the data, to maintain the “chain of custody” to ensure that
the design is based on real contextual data
– provide a shared focus for analysis now and, later, design
– provide intermediate deliverables, which can be important to your
working relationship with the customer
• Envisioned Design-Informing Models
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SOME GENERAL “HOW TO” SUGGESTIONS
• Maintain Connections to Your Data
• Extract Inputs to Design-Informing Models
• Use Your “Bins” of Sorted Work Activity Notes from Contextual Inquiry
and Contextual Analysis
• Represent Barriers to Work Practice
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USER MODELS
• Work Roles
– Sub-roles
– Mediated work roles
– Envisioned work roles
– Relationship of work roles to
other concepts
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Figure 6-2 Concepts defining and related to work roles.
USER MODELS
• User Classes
– Knowledge- and skills-based characteristics
– Physiological characteristics
– Experience-based characteristics
• novice or first-time user: may know application domain but not specifics of the
application
• intermittent user: uses several systems from time to time; knows application
domain but not details of different applications
• experienced user: “power” user, uses application frequently and knows both
application and task domain very well
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USER MODELS
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Figure 6-3 Relationships among work roles, sub-roles, and user class characteristics.
USER MODELS
• Social Models
– Identify active entities and represent as nodes
– Identify concerns and perspectives and represent as attributes of nodes
– Identify influences and represent as relationships among entities
– Social models in the commercial product perspective
– The envisioned social model
• User Personas
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USER MODELS
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Figure 6-4 Depiction of entities in the slideshow presentation social model. Thanks to Brad Myers, Carnegie Mellon University, and his colleagues for their case study (Cross, Warmack,& Myers, 1999) on which this example is based.
USER MODELS
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Figure 6-4 Depiction of entities in the slideshow presentation social model. Thanks to Brad Myers, Carnegie Mellon University, and his colleagues for their case study (Cross, Warmack,& Myers, 1999) on which this example is based.
USER MODELS
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Figure 6-6 Depiction of influences in the slideshow presentation social model.
USER MODELS
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Figure 6-7 Example social model for MUTTS.
USAGE MODELS
• Flow Model
– Creating a flow model diagram
– Flow models in the product perspective
– The envisioned flow model
• Task Models
– Tasks vs. functions
• Task Structure Models—Hierarchical Task Inventory
– Task inventories
– Task naming in hierarchical task inventories
– Avoid temporal implications in hierarchical task inventories
– Envisioned task structure model
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USAGE MODELS
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Figure 6-8 Example flow model from the slideshow presentation contextual inquiry. Thanks to Brad Myers, Carnegie Mellon University, and his colleagues for their case study (Cross, Warmack,& Myers, 1999) on which this is based.
USAGE MODELS
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Figure 6-9 Flow model of our version of MUTTS.
USAGE MODELS
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Figure 6-10 Envisioned flow model for the Ticket Kiosk System.
USAGE MODELS
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Figure 6-11 Hierarchical relationship of task A, the super-task, and tasks B and C, subtasks.
Figure 6-12 An incorrect hierarchical relationship attempting to show temporal sequencing.
USAGE MODELS
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Figure 6-13 Sketch of the top levels of a possible hierarchical task inventory diagram for MUTTS.
USAGE MODELS
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Figure 6-14 Partial HTI for MUTTS “sell tickets” task.
USAGE MODELS
• Task Interaction Models
– Usage scenarios as narrative task interaction models
– Elements of scenarios.
• Agents (users, people in work roles, often in personas, system, sensors)
• User goals and intentions
• User background, training, needs, etc.
• Reflections on work practice, including user planning, thoughts, feelings, and reactions to system
• User actions and user interface artifacts
• System responses, feedback
• User tasks, task threads, workflows, including common, representative, mission critical, and error and
recovery situations
• Environmental and work context (e.g., phone ringing)
• Barriers, difficulties encountered in usage
• And, of course, a narrative, a story that plays out over time
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USAGE MODELS
• Task Interaction Models
– Envisioned usage scenarios or design scenarios
– Step-by-step task interaction models
– Essential use case task interaction models
– Envisioned task interaction models
• Information Object Model
– Analyzing scenarios to identify ontology
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USAGE MODELS
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Figure 6-15 Branching and looping structures within step-by step task interaction models.
USAGE MODELS
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Figure 6-16 Task interaction branching and looping for MUTTS.
USAGE MODELS
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User Intention System Responsibility
1. Ticket seller to computer: Express intention to pay 2. Request to insert card
3. Ticket seller or ticket buyer: Insert card 4. Request to remove card quickly
5. Withdraw card 6. Read card information
7. Summarize transaction and cost
8. Request signature (on touch pad)
9. Ticket buyer: Write signature 10. Conclude transaction
11. Issue receipt
12. Take receipt
Table 6-1 Example essential use case: Paying for a ticket purchase transaction (with a credit or debit card)
WORK ENVIRONMENT MODELS
• Artifact Model
– Constructing the artifact model
• Physical Model
– Envisioned physical model
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WORK ENVIRONMENT MODELS
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Figure 6-17 Part of a restaurant flow model with focus on work artifacts derived from the artifact model.
WORK ENVIRONMENT MODELS
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Figure 6-18 Physical model for one slideshow presentation case. Thanks to Brad Myers, Carnegie Mellon University, and his colleagues for their example (Cross, Warmack, & Myers, 1999) on which this is based.
WORK ENVIRONMENT MODELS
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Figure 6-19 A physical model for MUTTS.
BARRIER SUMMARIES
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# Trigger Goal Barrier
18 Question from remote audience member
Answer questions Audio unintelligible. Local members instruct remote members to adjust audio setting.
19 Comment from remote member
Respond to comment Audio unintelligible. Local members instruct remote members to reconnect.
20 Comments from local members
Respond to comments by referring to slide from earlier in presentation
Presenter tries to return to slide. Presenter searches through slides rapidly but cannot find it.
21 Question from local member
Answer question Presenter tries again and eventually finds slide.
22 Local member asks presenter to bring up previous slide.
Go backward one slide Presenter tries to go back one slide but goes forward one slide instead.
23 Remote audience reconnected
Continue discussion
24 Question from remote member
Answer question
25 Comment from local member
Respond to question Presenter flips through slides searching for “system architecture” slide.
Table 6-2 Summary of selected barriers discovered within the step-by-step task interaction models for slideshow presentations
BARRIER SUMMARIES
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Description Model % of Talks Count (Over all Talks)
Average Severity
Average Duration (Each Time)
1. Changing slides is difficult and awkward because of the placement of the mouse or laptop. Physical 67 166 1.2 2 sec
2. Presenter loses track of time, must ask for verbal update. Sequence 44 6 1.5 55 sec
3. Reference provided is incomplete or skimmed over, audience members would be unable to find it after the talk.
Cultural 44 6 1 19 sec
4. Camera view is unclear or pointed at wrong information. Flow 33 3 1.7 60 sec
5. Audio level for demos is not set correctly. Flow 33 3 2 46 sec
Table 6-3 Summary of most frequent barriers observed in presentation cases
MODEL CONSOLIDATION
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Figure 6-20 Flow model from a group who observed and interviewed the event manager, event sponsors, the financial manager, and the database administrator.
MODEL CONSOLIDATION
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Figure 6-21 Flow model from a group who mainly observed and interviewed ticket buyers and ticket sellers.
MODEL CONSOLIDATION
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Figure 6-22 Flow model from a group who observed and interviewed the office manager, the advertising manager, and external advertisers.
ABRIDGED METHODS FOR DESIGN-INFORMING MODELS EXTRACTION
• Be Selective about the Modeling You Need to Do
• Designer-Ability-Driven Modeling
• Use a Hybrid of WAAD and Relevant Models
• Create Design-Informing Models on the Fly during Interviews
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Exercise 6-3: A Social Model for Your System
• Goal
– Get a little practice in making a social model diagram.
• Activities
– Identify active entities, such as work roles, and represent as nodes in the diagram.
– Include groups and subgroups of roles and external roles that interact with work roles.
– Include system-related roles, such as a central database.
– Include workplace ambiance and its pressures and influences.
– Identify concerns and perspectives and represent as attributes of nodes.
– Identify social relationships, such as influences between entities, and represent these as arcs between nodes in the
diagram.
– Identify barriers, or potential barriers, in relationships between entities and represent them as red bolts of lightning .
• Deliverables
– One social model diagram for your
• Schedule
– This could take a couple of hours.
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USER MODELS
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Figure 6-7 Example social model for MUTTS.
Exercise 6-5: Creating a Flow Model for Your System
• Goal: Get a little practice in creating a flow model for an enterprise.
• Activities:
– Follow up on your flow model initial sketch that you did in Exercise 4-1.
– Again represent each work role or system entity as a node in the diagram.
– Use arcs between nodes to show all communication and coordination necessary to do the work of the
enterprise.
– Use arcs to represent all information flow and flow of physical artifacts.
– Include all forms of communication, including direct conversations, email, phones,
• letters, memos, meetings, and so on.
– Include both flow internally within the enterprise and flow externally with the rest of the world.
• Deliverables
– One flow model diagram for your system, with as much detail as feasible.
• Schedule
– This could take a couple of hours.
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Flow Model 1
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Figure 4-3 An initial flow model sketch of the MUTTS system.
Flow Model 2.1
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Figure 6-9 Flow model of our version of MUTTS.
Flow Model 2.2
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Figure 6-10 Envisioned flow model for the Ticket Kiosk System.
Midterm Presentation Guideline
• Date/Time/Duration
– 1-2:50 pm Monday, 24th October 2015
– 2-2:50 pm Wendesday, 26th October 2015
– The length of a presentation : 5 mins
• Presentation Document Content
– System Concept Statement (Exercise 3-1)
– Flow Model I (Exercise 4-1)
– Social Model (Exercise 6-3)
– Flow Model II (Exercise 6-5)
• Post on your blog
– Due until 11:59 pm (Sun) 23rd Oct.
– Embed the presentation file from slideshare.
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