Requirements-definition User analysis. Sites .
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Transcript of Requirements-definition User analysis. Sites .
Sites http://riddle.pl/emcalc/
http://gallery.theopalgroup.com/selectoracle/
http://www.w3schools.com/
http://www.echoecho.com/csslinks.htm
HTML Validator |http://validator.w3.org/
CSS Validator | http://jigsaw.w3.org/css-validator/
Norman’s Theory of Action Proposes 7 stages of an activity
Establish a goal Form an intention Specify an action sequence Execute an action Perceive the system state Interpret the state Evaluate the system state with respect to the goals
and intentions
Theory of Action : Reading news on the web1. Set goal to find out about current news
decide on news website2. Form an intention
check out BBC website3. Specify what to do
move cursor to link on browser4. Execute action sequence
click on mouse button 5. Check what happens at the interface
see a new page pop up on the screen 6. Interpret it
read that it is the BBC website7. Evaluate it with respect to the goal
meets goals – read news
Theory of Action : Execution Turn on a light
1. Switch on button of lamp i.e. get more light (the goal).
2. To do this, one specifies how to move one's body,
3. how to stretch to reach the light switch and
4. how to extend one's finger to push the button.
The goal has to be translated into an intention, which in turn has to be made into an action sequence.
Theory of Action : ExecutionTurn on a light
Formulation of stages of execution:
1. Start with the goal, the state that is to be achieved.
2. Goal translated into an intention to do some action.
3. Intention must be translated into a set of internal commands, an action sequence that can performed to satisfy the intention.
4. Action sequence must be executed, performed upon the world.
Theory of Action : Evaluation After turning on light, evaluate if it is actually turned on. Judge how light affected our world. Formulation of stages of evaluation can be described as:
1. Evaluation starts with our perception of world.
2. Perception interpreted according to our expectations.
3. It is compared (evaluated) with respect to both our intentions and our goals.
Theory of Action : The gulfs Gaps between the user and interface
The gulf of execution The gulf of evaluation
Need to bridge gulfs to reduce the cognitive effort required to perform a task
Theory of Action : Gulf of execution Record a television show. You see the solution to the problem as simply pressing Record
button. However, to record a show requires, several actions :
1. Press the record button.2. Specify time of recording, usually involving several steps to change the hour
and minute settings.3. Select channel to record on - either by entering the channel's number or
selecting it with up/down buttons.4. Save the recording settings, perhaps by pressing an "OK" or "menu" or "enter"
button.
Difference between the user's perceived execution actions and the required actions is the gulf of execution.
Forgot my user name, I’ll get it here | User’s perceived execution action
Theory of Action : Gulf of execution
I need my Member ID? What’s that? | Required actions
Theory of Action : Gulf of evaluation
The gulf of evaluation Difficulty of assessing the state of the system and
how well it supports the discovery and interpretation of that state
Gulf of evaluation is small when system provides information about its state in a form that is: easy to get, is easy to interpret, and matches the way the person thinks of the system
Theory of Action : Gulf of evaluation
Amount of effort that the user must exert to interpret the physical state of the system and to determine how well his/her expectations and intentions have been met.
Goals, tasks, actions…
What's the difference? Goal - What the user aims to accomplish
E.g., purchase a book, locate information, get directions
Task What users believes must be done to accomplish the
goal E.g., browse product listing, enter credit card info
Action a task involving little or no problem solving
Goals, tasks, actions…
Donald Norman’s terms:The highest levels are activities, which are composed of tasks, which themselves are composed of
actions, and actions are made up of operations.
Goal: Make Web site with authoring tool Open Dreamweaver Make site definition Save page Make DB connection Up-load site View site
What about sub-tasks?
Hierarchical Task Analysis
Borrow a book from the library
go to the library
find required book
retrieve book from shelf
take book to counter
321 4
0
access catalog
access search screen
enter search criteria
identify required book
note location
plan 0: do 1-3-4. If book isn’t on the shelf expected, do 2-3-4.
plan 2: do 2.1-2.4-2.5.If book not identified from information available, do 2.2-2.3-2.4-2.5
2.1 2.2 2.3 2.4 2.5
Example: Goals, tasks, and actions
Goal: Get to Illinois
Tasks: Rent car, drive, get repairs
Action: Get gas
Example: Goals, tasks, and actions
Goal: Get to Illinois
Tasks: Rent car, drive, get repairs
Action: Get gas
The goal/task/action distinction is useful, but should not be applied rigidly
Discovery: Goals, tasks, and actionsGoal: on the Internet, buy either a purple stuffed dinosaur or a set of blocks for your two-year-old nephew. Your sister says either would be fine.
Discovery: Goals, tasks, and actions Task 1: Choose between a stuffed toy and
a set of building blocks
Action 1: Check Web for purple stuffed dinosaurs
Action 2: Check availability of the new blocks set
Action 3: Decide on one, based on price, availability, delivery, and gift wrap
Discovery: Goals, tasks, and actions
Task 2: Buy chosen toy
Action 1: Put toy into website’s shopping cartAction 2: Fill out billing and shipping information.
Task 3: Call sister; tell present is on its way
Action 1: Pick up phone/receiverAction 2: Dial phone number
What is a task analysis?
Involves learning about:users' goals what users want to do on your sitehow they work. specific tasks users must perform to their goalswhat steps are need to accomplish those tasks
Usability.gov : http://www.usability.gov/methods/analyze_current/analysis.html
What is a task analysis?
Allows you to discover: tasks Website must supportappropriate content scopewhat applications site should include
What is a task analysis?
Assist you in:refining navigation or search to better support
users' goals or building pages and applications that match
users' goals, tasks, and steps.
What is a task analysis?
Makes it possible to:define functions to be included within system accurately specify the user interface
http://www.usabilitynet.org/tools/taskanalysis.htm
Some Ways to analyze tasks…
Goals, tasks, and actions Job analysis Task list Task sequence Task hierarchies Observing and listening to users
Think aloudRole play | Focus groups | Surveys
Task Analysis | Steps1. Identify task to be analyzed
After establishing good understanding of users and tasks.
Identify several representative tasks that the system will be used to accomplish.
Task Analysis | Steps
2. Break tasks down into 4 to 8 subtasks. Cover whole area of interest.
3. Develop concrete, detailed examples of tasks users perform (or want to perform).
Task scenario
Task Analysis | Steps3. Draw subtasks as a layered diagram.
4. Decide upon level of detail to decompose tasks.
5. Continue decomposition.
6. Produce written account as well as decomposition diagram.
7. Present the analysis to someone else to check for consistency.
Step 2 | Detailed examples of tasks | ScenariosTask scenario Detailed narrative description. Describes current use of the system. Often detailed and personalized
Task Scenario (e-tickets)
Mary is an 85 year old women who is traveling alone. Her daughter brought her an e-ticket so she could visit for the Christmas holiday. The lines are long. She approaches the e-Ticket machine and selects here flight… She has never used an e-ticket machine… she has an enjoyable flight.
Marty is a 35 year old executive, who is late for a meeting. His flight was canceled and he has been transferred to another airline. The lines are long… He is engaged in a somewhat hostile phone conversation with a rental car agency as he approaches the e-ticket counter…. he has an enjoyable flight.
A task
Identify the major processes or tasks (e.g., money withdrawal and account inquiry) for which the ATM machine may be used.
For two of the major tasks (money withdrawal and account inquiry), write down the all the steps/tasks involved.
What impact on tasks/design?User Younger Middle Older
Age 12-25 25-50 50-80
Sex M/F M/F M/F
Phy limitations Varying height, hearing, sight
Some phy limits
Varying height, hearing, sight
Some phy limits
Varying height, hearing, sight
Some phy limits
Edu Minimal or none Only minimal Only minimal
Computer use Some Little or no Little of no
Motivation Very Maybe very Less motivated
Attitude Varies Varies varies
What impact on tasks/design?
Think of three people you know in these age groupsDo user characteristics impact your design?
Personas
Exercise: ATM scenario (1)
The task “withdraw cash using a card” can be described in a structured diagram and/or in a table format.
The table format allows the notation of additional information.
Textual notation describes the linear task solving process over time.
Scope of the task description was enlarged and additional subtasks were included.
Exercise: ATM scenario (2)
Scenarios
Task scenario Detailed narrative description. Describes current use of the system. Detailed and personalized
Techniques for observing and listening to users – to learn about tasks Think aloud: talk while doing the job Role playing Focus groups Mailed surveys
Think aloud
Facilitating user comments (ask user):Could you tell me what options you are
considering?
Is anything in particular puzzling you?
What might you do next?
Think aloud
BUT: No feedback, positive or negative
No answers or hints If users get stuck, have them go on Neutral demeanor at all times
Things to measures about tasks
Time to locate a book at the Barnes & Noble website Time to fill in customer information and place order Number of times the Back Button is used, indicating that user
cannot find desired information Number of clicks to find the time of a TV show Percentage of tasks completed correctly Number of calls to support line Number of complaints, negative facial expressions, or
regressive behaviors (screaming at monitor, etc.)