Understanding and conceptualizing interaction Chapter 2 Understanding and conceptualizing interaction

Understanding the problem space Understand and conceptualize Current user experience Current product Ways to improve current user experience/product

An example Problem: Providing drivers with better navigation and traffic information Question: What do we need to know before designing the system?

An example Understand the problem space: Find out problems with existing forms of navigating while driving Read maps while moving the steering wheel Look at a small navigation display when approaching a roundabout Ensure that drivers can continue to drive safely without being distracted

Understanding the problem space Framework Are there problems with an existing product or user experience? If so, what are they? Why do you think there are problems? How do you think your proposed design ideas might overcome these?

Understanding the problem space Framework If you have not identified any problems and instead are designing for a new user experience, how do you think your proposed design ideas support, change, or extend current ways of doing things?

From problem space to design space Having a good understanding of the problem space can help inform the design space e.g., what kind of interface, behavior, functionality to provide But before deciding upon these it is important to develop a conceptual model From: www.id-book.com

Conceptualizing the design space Describe what the system is going to be to the users, through developing a task-based conceptual model exploring the nature of the interaction that underlies user activities using different theories, models, and frameworks

Conceptual model A conceptual model is “a high-level description of how a system is organized and operates.” – Johnson and Henderson It is based on the task domain the system is supposed to support

Conceptual model A conceptual model outlines What people can do with a product What concepts are needed to understand how to interact with it

Conceptual model A conceptual model is not a description of the user interface But it is a structure outlining the concepts and relationships between concepts that will form the basis of the product or system

Conceptual model 4 components – Johnson and Henderson Metaphors and analogies Concepts: task-domain objects, objects’ attributes, operations performed on objects Relationships between concepts Mappings between concepts and task-domain the system is designed to support

Example Designing an online library catalog: Metaphors and analogies: the information is organized as in a physical card-catalogue

Example Concepts: item with attributes: title, ISBN, status; with actions: check-out, check-in, reserve subtypes of item, e.g., book, periodical issue, video periodical volume user account with attributes: name, items checked out librarian

Example Relationships: a book is one type of item, periodical volumes contain issues Mappings: each item in the system corresponds to a physical item in the library

Examples VisiCalc -> MS Excel Looked like a ledger sheet

A classic conceptual model: the spreadsheet Analogous to ledger sheet Interactive and computational Easy to understand Greatly extending what accountants and others could do www.bricklin.com/history/refcards.htm From: www.id-book.com

Examples Desktop interface Included a familiar knowledge of an office: papers, folders, filing cabinets, and mailboxes Drag and drop action similar to, e.g., moving a file and placing it in a folder

The Star interface From: www.id-book.com

Benefits of the conceptual model The conceptual model helps the design team To ask specific questions about how the conceptual model will be understood by the targeted users Not to become narrowly focused early on To establish a set of common terms

Interface metaphors A central component of a conceptual model Provide a structure similar to familiar entities but also have its own behaviors and properties E.g. search engine The similarities implied are at a general level

Benefits of a metaphor Help map familiar to unfamiliar knowledge Enable users to learn about the new domain Make learning new systems easier

Problems with interface metaphors (Nelson, 1990) Violate the cultural and logical rules e.g. a recycle bin placed on desktop Constrain designers in the way they conceptualize the problem space e.g. accessing a hierarchy of files Conflict with design principles e.g. an inconsistency use of a trash can on Mac

Problems with interface metaphors (Nelson, 1990) Constrain users’ understanding of the system in terms of the metaphor Emulate existing bad designs of physical objects Limit designers’ imagination in designing new paradigms and models

Conceptualizing the design space Describe what the system is going to be to the users, through developing a task-based conceptual model exploring the nature of the interaction that underlies user activities using different theories, models, and frameworks

Interaction Types Users’ interactions with a system or product 1) Instructing – users issue instructions to a system 2) Conversing – users have a dialog with a system

Interaction Types 3) Manipulating – users interact with objects in a virtual or physical space by manipulating them, e.g. opening, holding, closing, placing. 4) Exploring – users move through a virtual environment or a physical space

Instructing Varied ways of issuing instructions Benefits: e.g. pressing buttons, typing in strings of characters Unix & Linux OS: command-based systems Windows & GUI-based systems: control keys or the selection of menu options via a mouse Benefits: Quick and efficient

Conversing User having a conversation with a system Two-way communication process The system acting like a partner rather than a machine that obeys orders

Conversing Used for applications where users need to find out specific information or discuss issues Examples: advisory systems, help facilities, search engines Varied kinds: voice recognition, menu-driven systems, natural language-based systems

Benefits of conversing Allows people, esp. novice, to interact with a system in a way that is familiar to them makes them feel comfortable, at ease and less scared

Disadvantages of conversing Potential misunderstandings between the system and users i.e. systems can’t provide answers in a way that users expected Make a task cumbersome and one-sided interactions e.g. automated phone-based systems

Manipulating Manipulate objects by using users’ knowledge of how to manipulate objects in the physical world e.g. moving, selecting, opening, and closing

Direct Manipulation - Shneiderman (1983) Proposes that digital objects be designed so they can be interacted with analogous to how physical objects are manipulated Assumes that direct manipulation interfaces enable users to feel that they are directly controlling the digital objects

Core principles of DM Continuous representation of objects and actions of interest Rapid reversible actions with immediate feedback on object of interest Physical actions and button pressing instead of issuing commands with complex syntax

Benefits of DM Beginners can quickly learn basic functions Experienced users can rapidly carry out different kinds of tasks Infrequent users can remember how to perform functions over time

Benefits of DM Error messages are rarely needed Users can see immediate feedback of their actions Users feel less anxious Help users gain confidence and mastery and feel in control

Disadvantage of DM For some kinds of tasks, it is less efficient to use DM to accomplish the task e.g. spell checking

Exploring Moving through virtual 3D environment Moving through physical environment embedded with sensing technologies and location-detection technologies Exploit users’ existing knowledge of how they move and navigate through spaces

Examples 3D desktop virtual worlds where people navigate using mouse around different parts to socialize (e.g., Second Life) CAVEs where users navigate by moving whole body, arms, and head physical context aware worlds, embedded with sensors, that present digital information to users at appropriate places and times From: www.id-book.com

A virtual world From: www.id-book.com

Theories, Models, Frameworks A theory is a well-substantiated explanations of some aspect of a phenomenon Help identify factors (such as cognitive, social, and affective) relevant to the design and evaluation of interactive products

Models A model is a simplification of some aspect of human-computer interaction intended to make it easier for designers to predict and evaluate alternative designs Derived based on a theory Characterize aspects of human-computer interaction

Frameworks A framework is a set of interrelated concepts and/or a set of specific questions that is intended to inform a particular domain area Offers advice to designers as to what to design or look for Many forms: steps, questions, concepts, challenges, principles, dimensions

Frameworks Derived from Theories of human behavior Experiences of actual design practice Findings arising from user studies

Highly influential HCI framework Norman (1988) Explains relationship between the design of a conceptual model and a user’s understanding of it Depicts 3 interacting components: Designer User System

Designer’s model – the model the designer has of how the system should work Design Model Users Model User’s model – how the user understands how the system works Designer User System System Image System image – how the system actually works is portrayed to the user through the interface, manuals help facilities, etc.

Main differences Theories tend to be comprehensive, explaining human–computer interactions Models tend to simplify some aspect of human–computer interaction Frameworks tend to be prescriptive, providing designers with concepts, questions, and principles to consider

Key points Need to have a good understanding of the problem space specifying what it is you are doing, why, and how it will support users in the way intended

Key points A conceptual model is a high-level description of a product what users can do with it and the concepts they need to understand how to interact with it

Key points Decisions about conceptual design should be made before commencing any physical design Interface metaphors are commonly used as part of a conceptual model

Key points Interaction types (e.g., conversing, instructing) provide a way of thinking about how best to support the activities users will be doing when using a product or service Theories, models, and frameworks provide another way of framing and informing design and research