HAPPY WORLD USABILITY DAY!

1
HAPPY WORLD USABILITY DAY!

• Be sure to join Virginia Tech's Human Factors
  Engineering and Ergonomics Center (HFEEC)
  chapter of the Human Factors and Ergonomics
  Society (HFES) and the Laboratory for
  User-Centric Innovations in Design (LUCID) in
  affiliation with Virginia Tech's Center for
  Human-Computer Interaction (CHCI) in a
  celebration of World Usability Day 2008
  (http//www.worldusabilityday.org/) on today, 13
  November 2008, from 500pm - 600pm in Room 1110
  of the Knowledge Works II Building (KW 1110).
• REFRESHMENTS WILL BE PROVIDED! This year's
  theme is "Usability in Transportation" and we
  will be joined by Mr. Greg Fitch, Research
  Associate - VTTI's Center for Truck and Bus
  Safety. Greg, a Ph.D. candidate in Industrial and
  Systems Engineering, will be highlighting some
  innovative work in driver alert systems design in
  a talk titled "Communicating Integrated Collision
  Avoidance System Alerts through a Haptic Driver
  Seat".  A reception featuring light refreshments
  will follow Greg's talk. All are welcome in
  this our 3rd year of celebrating our
  contributions in "making life easy."

2
Agile software development and Scrum
3
Traditional waterfall lifecycle
4
The Star lifecycle model

• Suggested by Hartson and Hix (1989)
• Important features
• Evaluation at the center of activities
• No particular ordering of activities development
  may start in any one
• Derived from empirical studies of interface
  designers

5
The Star Model (Hartson and Hix, 1989)
6
Agile

• light-weight methods
• Goal of creating software in ways that are
• Lighter
• Faster
• more people-centric

7
Agile model emphasizes

• Individuals and interactions over processes and
  tools
• Working software over comprehensive documentation
• Customer collaboration over contract negotiation
• Responding to change over following a plan

8
Agile Manifesto 12 principles

1. Satisfy the customer through early and continuous
   delivery of valuable software.
2. Welcome changing requirements, even late in
   development.
3. Deliver working software frequently, in weeks to
   months (Timebox)
4. Business people and developers must work together
   daily throughout the project.
5. Build projects around motivated individuals. Give
   them the environment and support they need, and
   trust them to get the job done.
6. The most efficient and effective method of
   conveying information to and within a development
   team is face-to-face conversation.
7. Working software is the primary measure of
   progress.
8. Agile processes promote sustainable development.
   The sponsors, developers, and users should be
   able to maintain a constant pace indefinitely.
9. Continuous attention to technical excellence and
   good design enhances agility.
10. Simplicity--the art of maximizing the amount of
    work not done--is essential.
11. The best architectures, requirements, and designs
    emerge from self-organizing teams.
12. At regular intervals, the team reflects on how to
    become more effective, then tunes and adjusts its
    behavior accordingly.

9
In contrast to Waterfall model

• The waterfall model steps through
• requirements
• Capture
• Analysis
• Design
• Coding
• testing
• Progress is generally measured in terms of
  pre-planned sequence deliverable artifacts
• requirement specifications
• design documents
• prototypes
• code / implementation
• evaluation

10
Problems with waterfalladdressed by Agile

• Waterfall model
• separate stages
• commitments are made early on
• difficult to react to changes in requirements
• Iterations are expensive.
• Agile methods
• produce completely developed features (very small
  subset of the whole) every few weeks.
• smallest workable piece of functionality to
  deliver business value early
• continually improving it/adding further
  functionality throughout the life of the project.

11
Scrum

• For
• management of software development projects
• for running software maintenance teams
• program management approach

12
Roles divided into pigs and chickens

• based on the joke
• A pig and a chicken are walking down a road. The
  chicken looks at the pig and says, "Hey, why
  don't we open a restaurant?" The pig looks back
  at the chicken and says, "Good idea, what do you
  want to call it?" The chicken thinks about it and
  says, "Why don't we call it 'Ham and Eggs'?" "I
  don't think so," says the pig, "I'd be committed
  but you'd only be involved.
• pigs are committed to building software regularly
  and frequently
• everyone else is a chicken interested in the
  project but really irrelevant, though needs and
  desires are addressed

13
"Pig" roles

• Product Owner
• the voice of the customer
• writes User Stories, prioritizes them
• then places them in the Product Backlog.
• ScrumMaster Facilitator
• primary job is to remove impediments to the
  ability of the team to deliver the sprint goal.
• not the leader of the team (as they are
  self-organizing)
• acts as a buffer between the team and any
  distracting influences.
• The ScrumMaster is the enforcer of rules.
• Team
• responsibility to deliver the product.
• 5-9 people with cross-functional skills to do the
  actual work
• designer, developer etc.

14
"Chicken" roles

• Chicken roles
• not part of the actual Scrum process, but taken
  into account.
• involve / engage users, business and stakeholders
  in the process.
• provide feedback into the outputs for review and
  planning of each sprint.
• Users
• Stakeholders (Customers, Vendors)
• Managers (of users, organizations)

15
Roles in Scrum Process

• ScrumMaster (project manager) maintains the
  processes
• Product Owner represents the stakeholders
• Team developers
• During each sprint (15-30 day period)
• team creates an increment of potentially
  shippable (usable) software.
• features for sprint come from the product
  backlog, prioritized high level requirements of
  work to be done.
• planning meetings determine the backlog items
• Product Owner informs the team of the items in
  the product backlog
• The team determines how much they can commit to
  during the next sprint
• no one can change the sprint backlog, the
  requirements are frozen for a sprint.

16
(No Transcript)
17
The Scrum meeting scrum or the daily standup

• Project status meetingguidelines
• The meeting starts precisely on time.
• punishments for tardiness
• e.g. money, push-ups, hanging a rubber chicken
  around your neck
• All are welcome, but only "pigs" may speak
• The meeting is timeboxed at 15 minutes
• All attendees should stand (it helps to keep
  meeting short)
• The meeting should happen at the same location
  and same time every day
• During the meeting, each team member answers
  three questions1
• What have you done since yesterday?
• What are you planning to do by today?
• Do you have any problems preventing you from
  accomplishing your goal?

18
Retrospective end of sprint cycle

• every 15-30 days
• all team members reflect about the past sprint.
• purpose is to make continuous process
  improvement.
• This meeting is timeboxed at four hours.
• Two main questions are asked in the sprint
  retrospective
• What went well during the sprint?
• What could be improved in the next sprint?

19
Scrum principles

• Enables the creation of self-organizing teams
• by encouraging co-location of all team members
• and verbal communication across all team members
• recognition of requirements churn
• during a project the customers can change their
  minds about what they want and need
• unpredicted challenges cannot be easily addressed
  in a traditional predictive or planned manner
• As such, Scrum adopts an empirical approach
• accepting that the problem cannot be fully
  understood or defined
• focusing instead on maximizing the team's ability
  to deliver quickly and respond to emerging
  requirements.