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Designing Interaction

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  1. Designing Interaction Dewan Tanvir Ahmed, PhD University of Ottawa dahmed@site.uottawa.ca

  2. Chapter 3 – Interaction Design Process • Outline • Iterative Design • User-Centered Design • Interaction Design Models • Overview of Interaction Design Models Dewan Tanvir Ahmed

  3. Iterative Design • Interaction design is an iterative process • One step forward, two steps back • Solution do not happen in linear way • Essay writing • A list of the topics that you want to cover • Arrange them into an outline • Write draft • New Idea->change outline • change outline->change draft Dewan Tanvir Ahmed

  4. Iterative Design • Essay writing • Draft • Edited by someone else • Now draft becomes dynamic tool • Final drafts of documents are rarely created on the first attempt • Require a number of iteration Dewan Tanvir Ahmed

  5. Iterative Design • The knowledge path is constantly moving forward • Interaction design follows the same iterative trajectory • Moving forward through different phases but in an iterative framework Dewan Tanvir Ahmed

  6. User-Centered Design (USD) • How do designers come up with an interface that’s not in your face? That just does what you want, and doesn’t make you waste time doing what it wants? (IBM, 2006) • UCD can be regarded as a philosophy: • It places the user at the center of the design and development process right from the very beginning (the conception phase) and • checking at every step of the way with potential users to be sure they will be comfortable with the final design. Dewan Tanvir Ahmed

  7. User-Centered Design (UCD) • Pioneered by Donald Norman’s research laboratory at the University of California at San Diego. • The objective of UCD is • To develop a design framework that enables interaction designers to build more usable systems. • ISO Standard— defined in Human Centered Design Processes for Interactive Systems Dewan Tanvir Ahmed

  8. User-Centered Design • The design should emerge from the user’s • tasks • goals • environment • The process of UCD focuses on human-centric issues • cognition • perception • physical attributes and conditions • user • environment Dewan Tanvir Ahmed

  9. User-Centered Design • The basic tenants of user-centered design: • Early focus on users and their tasks • Continuous evaluations to determine ease of learning and ease of use • Iterative design Dewan Tanvir Ahmed

  10. User-Centered Design • UCD projects generally involve the following methods: • User Participation • Focus Groups • Questionnaires • Ethnographic Observations • Walkthroughs • Expert Evaluations • Usability Testing Dewan Tanvir Ahmed

  11. User-Centered Design - Methods • User Participation • Users become the part of the design team • Can provide constant contact with the target audience • Consulted at each step of design process • If development takes long time • These users actively involve in the design team • So less effective in representing the concerns of the target users • Improvement – How? • Some teams work on rotating basis • Target audience serve as members of the design team for limited periods • Replaced by new team! Dewan Tanvir Ahmed

  12. User-Centered Design - Methods • Focus Groups • are used to conduct structured interviews with various stakeholders • Allow designers to communicate with diverse users • And observe how they interact with each other Output: users opinions and attitudes • Focus group requires a moderator • To keep session on track • To see no one member dominates the discussion Dewan Tanvir Ahmed

  13. User-Centered Design - Methods • Questionnaires and surveys • Used to elicit information from large and geographically dispersed user groups • Can provides insights of user preferences and opinions • More restricted than focus group – WHY? • Because there is no contact with the person filling out the questionnaires. • Questions must be • phrased clearly and • Use intuitive scale for measurement Dewan Tanvir Ahmed

  14. User-Centered Design - Methods • Ethnographic Observations • It takes place at the location where the work is performed • The observer takes notes based on his observations • May use audio or video recording • Consent required • Ethnographic studies focus on compiling data about human cultures and societies Dewan Tanvir Ahmed

  15. User-Centered Design - Methods • Walkthroughs • It is performed by deciding on user goal or task and • Then walk through a design proposal to see whether that task can be accomplished • Objective – uncover any problem that might arise during actual use Dewan Tanvir Ahmed

  16. User-Centered Design - Methods • Expert Evaluations: • "An expert evaluation is a subjective analysis of a product's design, conducted by one or more usability experts". • Carried out by usability professionals • Uses heuristics or guidelines from usability research and human factors literature • Review is provided from three perspectives • Visual • Usability, and • Interaction • “The main goal is to identify any problems associated with the usability of products or user interfaces” Dewan Tanvir Ahmed

  17. User-Centered Design - Methods • Usability testing • Can be done using expensive usability laboratories using • Mirrors • Video camera • Tracking software and other observation equipment • Simply using • A paper prototype, an observer, and a subject • Usability tests are conducted throughout the design process and focus on different aspects of development! Dewan Tanvir Ahmed

  18. Interaction Design Models • Waterfall Model • Spiral Model • Dynamic Systems Development Method (DSDM) • Prototype-Based Models • Discount Usability Engineering • Contextual Inquiry Dewan Tanvir Ahmed

  19. What is Design – HCI? • It is a process: • a goal-directed problem solving activity informed by intended use, target domain, resources, cost, and feasibility • So it’s a creative activity • It’s a decision-making activity to balance trade-offs • It is a representation: • A plan for development • A set of alternatives & successive elaborations Dewan Tanvir Ahmed

  20. Interaction Design Models - Waterfall Model • The waterfall model was first defined by Winston W. Royce in 1970 based on his experience while • Developing Spacecraft missions • Planning • Commanding • Post-flight analysis Dewan Tanvir Ahmed

  21. Interaction Design Models - Waterfall Model • Requirements – • defines needed information, function, behavior, performance and interfaces. • Design – • data structures, software architecture, interface representations, algorithmic details. • Code – • source code, database • Test and Maintenance This has proven to be an untenable assumption, thus a leeway allowed for making adjustment to the previous stage after reviews are carried out! Dewan Tanvir Ahmed

  22. Interaction Design Models - Waterfall Model • Points to note • Good for small projects • Programmers are the users • Requirements are fixed, cannot be changed • Not user-centered Dewan Tanvir Ahmed

  23. Interaction Design Models - Waterfall Model • Advantages of the waterfall model: • Highly disciplined process of documentation • Easily observable development progress • Good for management control (plan, staff, track) • Easy to create budget • Consistent review process Dewan Tanvir Ahmed

  24. Interaction Design Models - Waterfall Model • Disadvantages of the waterfall model: • Document centric • All requirements must be known upfront • Can be difficult for customer to understand • Can give a false impression of progress • Does not reflect problem-solving nature of software development – iterations of phases • Integration is a problem at the end • Not user centered – • Little opportunity for customer to preview the system Dewan Tanvir Ahmed

  25. Interaction Design Models - Waterfall Model • When to use Waterfall Model • Requirements are very well known • Product definition is stable • Technology is well-understood • New version of an existing product is required Dewan Tanvir Ahmed

  26. Interaction Design Models - Spiral Model • Spiral Model developed by Barry Boehm (1988) • More complex but flexible • Requires knowledgeable design team • Centered on risk reduction • The model • Incorporates prototypedevelopment and encourages iteration • Starts with value proposition – • That usually identifies a particular corporate mission that could be improved by technology • This hypothesis is tested on each iteration by • Conducting risk analysis using prototypes of alternative designs • If a risk test fails the spiral, it is terminated; otherwise the process continues to final implementation Dewan Tanvir Ahmed

  27. Interaction Design Models - Spiral Model • The model addresses an important issue that keeps the software developer’s goals in synch with the firm’s changing environment • Spiral Model – • risk driven rather than document driven • High-risk activities cause schedule and cost overruns • Risk is related to the amount and quality of available information. The less information, the higher the risk • Example: Traveling The "risk" inherent in an activity is a measure of the uncertainty of the outcome of that activity Dewan Tanvir Ahmed

  28. Interaction Design Models - Spiral Model Dewan Tanvir Ahmed

  29. Interaction Design Models - Spiral Model • Breaks project into subprojects identifying specific risks • Budget and schedule predictability • System integration problems • User interface errors • Requirement instability resulting in code modification at a late stage • Mission-critical sensitivity to error • Investment versus productivity gains • High-level improvements that are incompatible with the client culture • Mismatches to the user project’s needs and priorities Dewan Tanvir Ahmed

  30. Interaction Design Models - Spiral Model • Advantages of the spiral model include the following: • Appropriateness for large-scale enterprise systems • Flexibility in terms of its sensitivity to the dynamic nature of the software industry • High sensitivity to risk at each stage of development • Disadvantages of the spiral model include the following: • Complex nature makes it difficult for customers to grasp • Requires extensive information regarding risk assessment • Undetected risks can be problematic Dewan Tanvir Ahmed

  31. Interaction Design Models - Dynamic Systems Development Method (DSDM) • Rapid Application Development (RAD) • Rapid application development (RAD) is a software development methodology that uses minimal planning in favor of rapid prototyping. • The Dynamic Systems Development Method (DSDM) • It’s a refined RAD approach • Developed by Not-for-profit consortium www.dsdm.org Dewan Tanvir Ahmed

  32. Interaction Design Models - Dynamic Systems Development Method (DSDM) • DSDM Framework is • Time-sensitive, and • Business-centered • 80% of a software solution can be developed in 20% of the time required to complete a total solution. • Constraints - Time frame and allocated resources are fixed • Functional requirements are flexible Main focus On-time delivery of high-quality software for current business needs Dewan Tanvir Ahmed

  33. Interaction Design Models - Dynamic Systems Development Method (DSDM) • Seven components – grouped into three stages • Iteration between the functional model iteration, design and build iteration, and implementation phases • Post-project phase Involves maintenance and reviews. May not involve previous design team Must be completed in sequential order Involves iterations. Project team determines its performance Dewan Tanvir Ahmed

  34. Interaction Design Models - Dynamic Systems Development Method (DSDM) • Pre-Project • Feasibility Study – • Finding out if and how the project will work out Business Study – Studying the business aspects of the project. Does it make good business sense? • Who are the participants and interested parties? • What is the best work plan? What is needed to: • Build it • Test it • Deploy it • Support it? • What technologies will we be using to build and deploy it? Dewan Tanvir Ahmed

  35. Interaction Design Models - Dynamic Systems Development Method (DSDM) • Functional Model •  A functional prototype is a prototype of the functions the system should perform and how it should perform them. Prototypes cover many different aspects of the system: Business – Usability - how easy is it to use? Performance and Capacity – can it handle the volume and frequency of use that it will receive? Technique - What's the best way of going about solving the problem? • Prototyping follows these steps: • Investigate • Refine • Consolidate Dewan Tanvir Ahmed

  36. Interaction Design Models - Dynamic Systems Development Method (DSDM) • Design And Build • In this stage, the product is designed and developed in iterations. • In each iteration a design model is made of the area being developed, and • Afterward area is coded and reviewed. Dewan Tanvir Ahmed

  37. Interaction Design Models - Dynamic Systems Development Method (DSDM) • Implement • In this stage the product is wrapped up • documentation is written, and • a review document is drawn up • comparing the requirements with their fulfillments in the product. • The users are trained in how to use the system, and the users give approval to the system. Dewan Tanvir Ahmed

  38. Interaction Design Models - Dynamic Systems Development Method (DSDM) • Post-phase (maintenance ) • After the product is created, maintenance will inevitably need to be performed. • This maintenance is generally done in a cycle similar to the one used to develop the product. Dewan Tanvir Ahmed

  39. Interaction Design Models - Dynamic Systems Development Method (DSDM) • The DSDM framework recognizes nine principles: • Active user involvementis imperative. • The team must be empoweredto make decisions. • The focus is on frequent delivery of products. • Fitness for business purpose is the essential criterion for acceptance of deliverables. • Iterative and incremental development is necessary to converge on an accurate business solution. Dewan Tanvir Ahmed

  40. Interaction Design Models - Dynamic Systems Development Method (DSDM) • The DSDM framework recognizes nine principles: • All changesduring development are reversible. • Requirementsare baselined at a high level. • Testing is integrated throughout the life cycle. • Collaboration and cooperation among all stakeholders is essential. Dewan Tanvir Ahmed

  41. Interaction Design Models – DSDM: Core Techniques • The DSDM Core Techniques • A number of techniques involved in the DSDM framework are applied according to their appropriateness to a particular project! • Facilitated Workshops • Project stakeholders are involved • Used to manage to fast pace of the process • Engage business community in the design process • Objective: • Foster rapid, quality decision making Dewan Tanvir Ahmed

  42. Interaction Design Models – DSDM: Core Techniques • Timeboxing • All projects have fixed completion date – thus the timebox • Design activities are nested within the timebox and must be concluded within the prescribed timebox • Three Phases • Investigation • QUICK pass • Determines whether the team is on target and moving in the right direction • Refinement • Use the result of investigation • Refine the design if needed • Consolidation • Wrap-up phase • All loose ends are accounted for and adjusted Dewan Tanvir Ahmed

  43. Interaction Design Models – DSDM: Core Techniques • MoSCoW(prioritize requirements) • Must have • Fundamental to the system • Without them system is unworkable and useless • Project guarantees to satisfy a minimum usable subset • Should have • Important requirements • Mandatory in less time-constrained development • System will useful and usable without them • Could have • Requirements that can more easily be left out of the increment under development • Won’t have • Want to have but won’t have this time Dewan Tanvir Ahmed

  44. Interaction Design Models – DSDM: Core Techniques • Modeling • It is recommended • Ensures minimum misunderstanding between business and design communities • Models are usually project depended • Prototyping • Business—Demonstrate the business processes being automated. • Usability—Demonstrate how the user interacts with the system. • Performance and Capacity—Test for system robustness. • Capability/Technique—Test conceptual designs. • Testing • Take place throughout the life cycle • Configuration Management • Require a strong and highly organized management structure Dewan Tanvir Ahmed

  45. Interaction Design Models - Dynamic Systems Development Method (DSDM) • Advantages of the DSDM: • Provides a technique-independent process • Flexible in terms of requirement evolution • Strict time and budget adherence • Incorporates stakeholders into the development process • Disadvantages of the DSDM: • Involves progressive development of requirements • Focus on RAD can lead to decrease in code robustness • Requires full commitment to DSDM process • Requires significant user involvement • Requires a skilled development team in both the business and technical areas Dewan Tanvir Ahmed

  46. Interaction Design Models - Prototype-Based Models • Prototypes are used to develop, demonstrate and test design ideas • Appropriate for small-scale projects • Enable discussions of: • Look and feel • Scope • Information flow • Product concept Dewan Tanvir Ahmed

  47. Interaction Design Models - Prototype-Based Models • Throwaway Prototyping Model • Also called Rapid Prototyping • Used when a client is not clear about the scope of the project • cannot accurately describe the project requirements • It is built and used to elicit requirements • How does it work? • Put together a team of “Smart Guys” from multiple disciplines • Develop the GUI on Paper • Code the GUI in a fast language (Make it look like it’s working) • Show it to the clients • Get Feedback Dewan Tanvir Ahmed

  48. Interaction Design Models - Prototype-Based Models • Customer - This is great, … When can we have it? • Developer - it’s only a prototype, we will throw it away and start over • Customer – Oh, No. this is exactly what we need …. Dewan Tanvir Ahmed

  49. Interaction Design Models - Prototype-Based Models • Evolutionary Prototyping Model • The goal • Build a very robust prototype in a structured manner, and • Constantly refine it  • Risk is associated! – why? • To minimize risk • The developer does not implement poorly understood features.  • Developers can focus themselves to develop parts of the system that they understand instead of working on developing a whole system. Dewan Tanvir Ahmed

  50. Interaction Design Models - Prototype-Based Models • Advantages of prototyping include the following: • Easy for users to give feedback • Reduced development time and cost • Involvement of the user in the development process • Disadvantages of prototyping include the following: • Can be viewed by client as the final product • May lead to insufficient analysis due to the ease of development • Difficult for developers to discard and start creating the final product from scratch Dewan Tanvir Ahmed