1. Chapter 2: Understanding and conceptualizing interaction
It is important to have a clear understanding of why and how you are going to design something before you start writing lines of code or mock-up an user interface. This ensures that ill-thought out ideas and designs and such other incompatible models are not developed.

2. Understanding the problem space
What do you want to create?
What are your assumptions?
What are your claims?
Use of Augmented reality for everything might not be the best way to do things. IN general it doesn’t make sense to decide on what kind of interface or what the end tool is before you understand the nature of the problem and the nature of the user interaction.
Usability and user experience goals must be understood before you can understand the problem space. You need to understand the assumptions(things that you can take for granted) and claims(stating something to be true, when it is still open to question). It is a good idea to write down the various assumptions and claims and try and defend them. This helps ensure the you understand the problem space better. Typically, this is done as a group, the team as a whole tries to talk through the various assumptions and claims, sometimes, different people have different perspectives on things, getting to consider all perspectives ensures this will be of great benefit to the team in the long run. When you make claims about product success it is important to ask yourself Will it achieve what you hope it will? If so, how?

3. A framework for analyzing the problem space
Are there problems with an existing product or user experience?
Why do you think there are problems?
How do you think your proposed design ideas might overcome these?
When designing for a new user experience how will the proposed design extend or change current ways of doing things?

4. Conceptual model
“a high-level description of how a system is organized and operates.” (Johnson and Henderson, 2002, p. 26)
Having a good understanding of the problem space can help inform the design space e.g., what kind of interface, behavior, functionality to provide. You need to first think about how the system will appear to users (i.e. how they will understand it)
It is not a description of the user interface but a structure outlining the concepts and the relationships between them. It enables “designers to straighten out their thinking before they start laying out their widgets” (p. 28). It provides a working strategy and a framework of general concepts and their interrelations

5. Main components Metaphors and Analogies. Concepts Relationships
Concept  User Experience Goals.
Major metaphors and analogies that are used to convey how to understand what a product is for and how to use it for an activity. Concepts that users are exposed to through the product and the relationship between the concepts. e.g., one object contains another. The mappings between the concepts and the user experience the product is designed to support. Just like developing an ER model, people might feel comfortable, developing the actual interface, drawing the screen, positioning the widgets rather than thinking about it from an abstract sense.

6. Benefits How do users understand the interaction model?
Not to become narrowly focused early on
Establish a set of common terms they all understand and agree upon
Reduce the chance of misunderstandings and confusion arising later on
Orient themselves towards asking questions about how the conceptual model will be understood by users. Establish a set of common terms they all understand and agree upon to help reduce the chance of misunderstandings and confusion arising later on

7. A classic conceptual model: the spreadsheet
Analogous to ledger sheet
Interactive and computational
Easy to understand
Greatly extending what accountants and others could do
It was simple, clear, and obvious to the users how to use the application and what it could do
It on user’s familiarity with ledger sheets
Got the computer to perform a range of different calculations and recalculations in response to user input

8. The Star interface
8010 Star office system targeted at workers not interested in computing per se. The idea here was to make the computer invisible to the user. Spent several person-years at beginning working out the conceptual model. They chose the analogy of an office environment, except that the workers will be manipulating virtual objects instead of the real objects. So you got the concepts of documents being maintained in files and stored in folders and cabinets and the use of picture icons to represent these concepts. They also developed new concepts such as placing a document on a printer for printing it etc.
Simplified the electronic world, making it seem more familiar, less alien, and easier to learn

9. Interface metaphors
Designed to be similar to a physical entity but also has own properties
e.g. desktop metaphor, search engine
Exploit user’s familiar knowledge, helping them to understand ‘the unfamiliar’. It conjures up the essence of the unfamiliar activity, enabling users to leverage of this to understand more aspects of the unfamiliar functionality
People find it easier to learn and talk about what they are doing at the computer interface in terms familiar to them

10. Benefits of interface metaphors
Makes learning new systems easier
Helps users understand the underlying conceptual model
It can be innovative and enable the realm of computers and their applications to be made more accessible to a greater diversity of users

11. Problems with interface metaphors (Nelson, 1990)
Break conventional and cultural rules
e.g., recycle bin placed on desktop
Can constrain designers in the way they conceptualize a problem space
Conflict with design principles
Forces users to only understand the system in terms of the metaphor
Designers can inadvertently use bad existing designs and transfer the bad parts over
Limits designers’ imagination in coming up with new conceptual models

12. Interaction types Instructing Conversing Manipulating Exploring
Another way of conceptualizing the design space is in terms of the users interactions with a system or product.
Instructing
issuing commands using keyboard and function keys and selecting options via menus
Conversing
interacting with the system as if having a conversation
Manipulating
interacting with objects in a virtual or physical space by manipulating them
Exploring
moving through a virtual environment or a physical space

13. Instructing Where users instruct a system by telling it what to do
e.g., tell the time, print a file, find a photo
Very common interaction type underlying a range of devices and systems
A main benefit of instructing is to support quick and efficient interaction. It is good for repetitive kinds of actions performed on multiple objects

14. Conversing Like having a conversation with another human
Examples include search engines, advice-giving systems and help systems
Differs from instructing in that it more like two-way communication, with the system acting like a partner rather than a machine that obeys orders
Ranges from simple voice recognition menu-driven systems to more complex ‘natural language’ dialogues
GOOG
PROS and CONS:
Useful for technophobes, they are less scared and gives them a confident to interact with the system. There is a good change of misunderstanding(phone based systems)

15. Manipulating
Exploit’s users’ knowledge of how they move and manipulate in the physical world
Virtual objects can be manipulated by moving, selecting, opening, and closing them
Tagged physical objects (e.g., bricks, blocks) that are manipulated in a physical world (e.g., placed on a surface) can result in other physical and digital events. Blocks with RFID tags to teach children how to mix colors. It has been shown that children are more creative in mixing colors when using this model rather than when using a digital or a physical cubes.

16. Direct manipulation
Proposes that digital objects be designed so they can be interacted with analogous to how physical objects are manipulated
Shneiderman (1983) coined the term Direct Manipulation. It came from his fascination with computer games at the time. Assumes that direct manipulation interfaces enable users to feel that they are directly controlling the digital objects

17. Core principles of DM
Continuous representation of objects and actions of interest
Physical actions and button pressing instead of issuing commands with complex syntax
Rapid reversible actions with immediate feedback on object of interest
According to these principles, the object on the screen remains visible as the user interact with it and any actions performed on it are immediately visible.

18. Why are DM interfaces so enjoyable?
Novices can learn the basic functionality quickly
Experienced users can work extremely rapidly to carry out a wide range of tasks, even defining new functions
Intermittent users can retain operational concepts over time
Error messages rarely needed
Immediate feedback
Users gain confidence and mastery and feel in control

19. What are the disadvantages with DM?
Not all tasks can be described by objects and not all actions can be done directly
Some tasks are better achieved through delegating rather than manipulating
e.g., spell checking
Moving a mouse around the screen can be slower than pressing function keys to do same actions

20. Exploring
Involves users moving through virtual or physical environments
physical context aware worlds, embedded with sensors, that present digital information to users at appropriate places and times . Automatic lights, smart home, ambient wood, Lilly Arbor project.

21. A virtual world
3D desktop virtual worlds where people navigate using mouse around different parts to socialize (e.g., Second Life)

22. A CAVE CAVEs where users navigate by moving whole body, arms, and head
Which interaction type is the best?
Coupling – Tight(visibility is important) versus loose(games)

23. Let’s inspect your project
As a team look at your use cases:
What is the ideal interaction type to accomplish each use case?
Instructing
Conversing
Manipulating
Exploring

24. Now look at your screens
Is the “ideal” type of interaction you just chose actually expressed on each of your related screens?

25. Brainstorm
A list of “improvements” you could make to your screens, based on a better choice of interaction types.
Explain to the class how each of these new these choices is based on your analysis