Human-Computer Interaction Questions


(Fall 2012 - Hartmann & Agrawala):

Q1: Direct Manipulation and Computational Wear

* List the core principles of direct manipulation user interfaces.
* Consider two types of mobile UIs: touch-controlled and voice-controlled.
  Which type of interface is more "direct" and why?
* Draw the user-system dialog. Where do articulatory and semantic
  distances appear? What is the difference between them? Give a concrete
  example how interfaces may reduce one type of distance.
* What are computational forms of "wear" and how do they conceptually
  fit into the direct manipulation paradigm?

Q2: Contextual Inquiry from Beyer and Holzblatt

Describe the relationship that should hold in contextual inquiry between
researcher and subject.

List the four principles of contextual inquiry (Context, Partnership,
Interpretation, Focus).For each principle, give concrete examples of *how*
it should be applied, and *why* it contributes to understanding of user

Q3: Evaluation Methods
* Tohidi et al. claim that "Testing many is better than testing one".
  What concrete evaluation methodology do they argue for - and what
  advantages do they claim?
* Kohavi also advocates for testing alternatives - contrast his approach
  with Tohidi et al.'s. What are the strengths and limitations of each
  approach? At which stage of design is each appropriate?
* You are building a website and want to increase the time your users
  spend on the site. Think of a design intervention and how you would
  test it. What would your independent and dependent variables be? What
  kind of statistical tests would you apply and what would they tell you
  about the results?

Q4: End-User Software Engineering from the reading by Andrew Ko et al.

How did Ko et al. define "end-user software engineering"?

List the 5 stages of EUSE practice (Requirements, Design and Specification,
Reuse, Testing, Debugging).Using these 5 stages, contrast the practices of
EU programmers and professional programmers.

In the process, list some common EU programming examples (spreadsheets,
web design, scripts,...)

(Spring 2012 - Hartmann & Agrawala):

* What are the differences between an absolute, a relative,
  a direct and an indirect input device as defined by Hinckley?
  Give an example for each.
* What is gain, or c:d ratio, and how does it apply to direct
  and indirect devices?
* The 3-state model of input: What are the three states?
  How does the three-state model help designers reason about input devices
  and appropriate interaction techniques? Discuss at least two devices
  and their differences. Draw diagrams if you think it will help your argument.
* What is a morphological design space and why would one create
  such a space for input devices? 

* What is the difference between nominal, ordinal and quantitative
  variables?  Give an example of each. 
* Name several retinal properties of marks and explain whether each
  retinal property is effective for depicting nominal, ordinal
  and/or quantitative data.
* Some visual variables are better than others for depicting
  quantitative data.  Pick two visual variables (say position and
  grayscale) and describe how you would design an experiment to test
  which of the two visual variables is more effective for quantitative

* List the five themes from the How Bodies Matter. Briefly describe
  how each theme argues for embodied interaction and give an example.
* What is tacit knowledge and why would we care about it in the design
  of interfaces?
* What are the similarities and differences in perspective between
  direct manipulation and embodied interaction?

* What is information scent?
* You are designing a search user interface to compete with Google.
  Explain strategies you might use for maximizing information scent
  during web search.
* A redesign led to lower click-through rates. Argue whether this
  should be interpreted as higher or lower scent.
* What is faceted metadata and why is it useful for browsing?

* What is Fitts' Law?
* What are the basic assumptions of the Fitts' Law model.
* What is the steering law? Researchers have experimentally learned that
  we can model another constrained pointing task as: (draw two
  goal-crossing version of task), using a similar formula (write
  two-goal formula on board).  How would you extend this approach to
  derive the steering law?

(Spring 2009 - Agrawala & Canny):
"Q1: Gould and Lewis' User-Centered Design and Contrast with CI

What were the principles in Gould and Lewis' paper?
Contrast that papers user focus with Contextual Inquiry

Q2: Fitts' Law?

Derive Fitts' Law?
What are the assumptions of the Fitts' Law model.
How would you extend the law to 2D?
How would you account for pointer size in Fitts' law?

Q3:  Visual Variables

What is the difference between nominal, ordinal and quantitative variables?
What are retinal properties of marks?
Name several retinal properties of marks.
Explain whether each retinal property is effective for depicting
nominal, ordinal and/or quantitative data.
What encoding does a bar chart use to depict values? What encoding
does a pie chart use? How would you design a quantitative user study
comparing the effectiveness of these two types of charts. 

Q4: Heuristic Evaluation

Describe Nielen's Heuristic Evaluation method: What steps comprise it,
how and where is it used, how many evaluators are recommended, and
where do the heuristics come from?"

(Fall 2008 - Agrawala & Canny):
"Q1: Fitts' Law
What is Fitts' Law? What are the assumptions Fitts'
Law is based on? Why is there a log term in it (i.e.
derive Fitts' Law). How would you extend Fitts' law
to 2D? 

Q2: Paper Prototyping
Why is paper appropriate for prototyping? What do people prototype
with paper? What are its advantages and disadvantages? Why did
Landay and Myers propose a digital system (SILK)?  What are its
advantages and disadvantages? 

Q3:  Heuristic Evaluation (Nielsen paper).
What is Heuristic Evaluation? Why is it used? Outline the steps
involved. How is HE typically used across an entire design cycle? How
many evaluators are recommended? What are some differences between HE
and normal user studies? What are the two sets of heuristics and
where do they come from? 

Q4: Visualization Reference Model
What is the reference model for visualizations?
Why is this model important for visualization? How is it used?
What is the relationship to of this model to the
Model View Controller architecture?"

(Spring 2008 - Agrawala & Canny):
"Q1: Ubicomp 

In Weiser's article he presents the idea of 3 scales of devices
(inch-scale, foot-scale and yard-scale). Describe each scale and
name as many unique affordances as you can at each scale.

Describe a new application that is uniquely suited to each scale
but not the other two. 

Q2: Design principles for input devices.

Describe the design space for input devices from the paper on
"Design Morphology" by Card et al. How does this paper do
enumeration of complex input devices from basic components?
What are effectiveness and expressiveness? What are desirable
features generally for input devices?

Q3: Scientific Method

What are independent, dependent, control and random variables? Give an
example of each. What is a confounding variable? 

What are between subjects and within-subjects experiments? Explain the
pros and cons of each 

Suppose you have developed a new multitouch interface for browsing a
collection of images.  You want to rigorously compare your interface
to a mouse-based interface using the scientific method
(i.e. hypothesis testing).

State a testable hypothesis and explain what the independent and
dependent variables of your experiment will be. Then state the
corresponding null hypothesis.

Q4: Budget ethnography

Describe what budget ethnography is, and how it is executed?
What were some high-level differences between the approach of 
this paper to observation and contextual inquiry, which is
one of the methods used by this paper?"

(Spring 2007 - Agrawala & Canny):
"Q1: Paper Prototyping
What is paper prototyping and how is it used? What are
the advantages and disadvantages of it? What is Landay and
Myers' SILK system? What are its advantages and disadvantages?

Q2: The psychopathology of everyday things
What are "natural signals?" What are affordances? Where do they 
come from, i.e. why should people share such understandings?
What is a conceptual model? Give an example. What is the role of
"mappings" in HCI design? What is the "designers dilemma" discussed
in Norman's chapter? 

Q3: Fitts' Law
What is Fitts' Law? What are the assumptions Fitts' Law is based on? 
Why is there a log term in it (i.e. derive Fitts' Law). How would you 
extend Fitts' law to 2D? 

Q4: Tangible User Interfaces.
Describe the three main classes of TUIs as per Ishi's paper. Give
an example of each type. For each example, say what the advantages of
a tangible interface are for that problem. Finally, what general metaphor
did Ishi propose for tangible UIs?"

(Spring 2004 - Canny & Mankoff):
1)  UI design principles question: 
    (Gould and Lewis reading, Beyer and Holtzblatt)

    What were the main principles for User-centered design laid out by G&L? Explain these. 

    How did the G&L approach to the user differ from the contextual inquiry approach? 

2)  GOMS question:
    Define GOMS, apply KLM to a clicking task (simple yes/no dialog box). Explain actual 
    timings using Human Info Processor. Explain why it only applies to experts. Think about 
    whether GOMS applies to a person with motor impairments.
    Why is paper appropriate for prototyping? What do people prototype with paper? What are 
    its advantages and disadvantages? Why did Landay and Myers propose a digital system (SILK)? 
    What are its advantages and disadvantages?

4)  ARKOLA Question: What was the motivation for the ARKOLA experiment? What were the benefits 
    of using sound? What were problems with the way sounds were designed? How were the sounds 
    designed? Discuss relationship with testing of noticeability.

(Fall 2003 - Canny & Mankoff):
"1) Heuristic Evaluation
2) Mobile Device
3) Information Visualization
4) Mixed-Initiative"

(Spring 2003 - Canny & Mankoff):
1)   a) Sketch the human-centered design cycle used for user interface design.
     b) Give some principles for building effective early (low-fidelity) prototypes.
     c) Explain scenarios and their role in design.
     d) (building on c) Explain one or more view(s) of an interface prototype that a 
        designer would want.

2)   a) Name one mostly qualitative evaluation technique and one mostly quantitative or 
        empirical evaluation technique.
     b) Name three key factors that you would use to decide which technique to apply when 
        designing an interface
     c) Suppose you did a study using the empirical technique and found that your interface 
        successfully allowed a user to complete three tasks that you had chosen to test. On 
        what grounds, specific to the technique you chose,  might you refute such an evaluation?
3)   a) Define Context and Context Awareness.
     b) Define primary and secondary context (as per Abowd and Dey). 
     c) Give a taxonomy of types of context.

4) Two approaches to ubiquitous computing are to place the infrastructure in the environment 
   or to place the infrastructure on the body. This applies to decisions on where sensing 
   occurs, where information is stored and where information is processed. 
     a) Select one concrete example application from the literature. Was a body or environmental 
	  approach used? Is this justifiable for technological reasons, human reasons, both, or 
	  neither in your opinion?
     b) From a technical perspective, discuss the advantages and disadvantages of environmental 
	  versus body approach on the basis of sensing, storage and computation.
     c) From a human perspective, discuss the advantages and disadvantages of environmental 
	  versus body approach on the basis of sensing, storage and computation.

(Fall 2002 - Landay & Mankoff):
1) Give an overview of GOMS
     a) What does GOMS stand for and describe each piece?
     b) What are the advantages & disadvantages?
     c) Give an overview of how one runs a GOMS analysis
     d) How might we take advantage of GOMS for automated usability testing?  

2) Card, Mackinlay and Robertson present a model of input devices in their 1992 paper.
     a) What are its limitations
     b) What other issues and innovations in input should be considered in a comprehensive 
	  description of input?
		-two handed input
		-input transformations (e.g. soft keyboards)
		-intelligence, prediction, etc.

3) MVC architecture
     a) What does MVC stand for and describe each piece? (draw a diagram)
     b) What are the advantages of MVC?
     c) How is MVC often employed in practice? (hint: Which components are grouped & why)

4) Grudin describes challenges for groupwear developers, and Abowd and Mynatt describe some 
   of the issues in evaluating ubicomp systems.
     a) From an evaluation perspective, are there any common problems among any of these 
     b) Is "scientific" evaluation possible in these domains? What role does empirical 
        evaluation and quantitative data have to play in designing and evaluating these 
(Spring 2002 - Canny & Landay):
1) Conceptual Models
     a) What is a conceptual model?
     b) How is it communicated or learned?
     c) What happens when the user's conceptual model differs from the designer's intended 
	  conceptual model?
     d) Should the conceptual model match the model of the underlying system?  Why or why not?
2) Mark Weiser's papers articulated a vision of ubiquitous computing and calm technology. 
     a) List some parts of this vision which have been realized (or are happening now), and 
	  some which have not.
     b) For the examples that have not been realized, explain why you think they haven't.
3) Agents vs. Direct Manipulation
     a) What is the debate between direct manipulation and agents?
     b) Is there a middle ground between these two positions?

4) Heuristic Evaluation
     a) Briefly describe the steps in conducting a Heuristic Evaluation
     b) How does the typical number of usability violations found depend on the number of 
	  testers? How should you choose the best number of testers?
     c) What problems are there with averaging severity ratings, and how can you deal with 

(Fall 2001 - Canny & Landay):
"Q1: Contextual Inquiry (CI)
a) Describe how to carry out a Contextual Inquiry.
b) What is the metaphor used for the interaction with the participants? Why is this metaphor good?
c) Why is CI better than interviewing or observing alone?  What do you do with the data? What type 
   of organizational techniques are used?
d) What do you do with the resulting data and what are some techniques used to organize it?
e) In what type of development situations is it hard to apply CI?

Q2: Design
a) What is an affordance? Give an example of an affordance in a real world, physical object and 
   in a user interface.
b) What is a conceptual model? What happens if the user's conceptual model does not match the 
   designers conceptual model?
c) What does mapping mean in terms of UI design? What kind of mappings make Uis easier to use 
   and understand?

Q3: Visualization
a) Describe focus+context visualization
b) What are the advantages of focus+context?
c) What are the disadvantages of focus+context?

Q4: Speech
Can you directly translate a GUI into a SUI (Speech UI)? Is it reasonable to? If not, what are 
the problems? Contrast the "shapes" of typical GUI and SUI command hierarchies."

(Fall 2000 - Canny & Landay):
"Question 1: Usability Evaluation

a) What are the tradeoffs between Heuristic Evaluation and traditional user testing?

b) Remote usability-evaluation is a hot area in HCI.  This method places the participant 
   in the evaluator in different locations and possibly working at different times (usually 
   each is in their regular workplace). Why would usability professionals be interested in it?

d) What are some of the drawbacks to remote usability evaluation?

e) Log file analysis is one way of doing remote usability evaluation for web sites.  What are 
   the advantages and disadvantages of this approach?

f) Which current usability techniques would be easier to deploy in a remote way?  Which might 
    be harder to deploy?  Why?

g) How might remote testing augment traditional usability evaluation?

Question 2: Education.
a) Describe the "Kidsim" paper and its main results. Relate these to the ideas on pedagogy 
   from the Papert readings. In particular:

b) Why did they take the approach that they did? What where the justifications for PBD and 

c) How did they do it? What were the implementation decisions?

d) What did they discover when they tried it?

e) Finally critique the approach in the paper and suggest improvements.

Question 3: Model-based UIs
UIDE represented a new way to implement a UIMS. 

a) Describe the model based approached.

b) What are its advantages?

c) The model based approached has not caught on in industry (i.e., in commercial tools).  
   Why might that be so and how might we go about improving this situation?

Question 4: Group Communication.
Imagine you are managing an interdisciplinary group with members split among two distant 
locations. Referring to the Dourish and Bellotti paper, and to Elena Rocco's paper, describe 
how you would manage communication between the two geographic subgroups."

(Spring 2000 - Canny & Landay):
"Q1: Interactors - Define Interactors.  What are some of the typical behaviors? Drawbacks? 
Discuss the separation between graphic feedback and underlying control, and the correspondence 
between the interactor and the controller in MVC.

Q2: Interaction Modes - Contrast speech and graphical UIs. Compare tangible interfaces and 
    GUIs. List some physical limitations of TUIs.

Q3: Model-Human Processor - Describe the MHP. Describe the relevance to current UIs in terms 
    of GOMS evaluations and in design. 

Q4: Collaboration - Summarize Elena Rocco's results and their use of dilemma games. Discuss 
    Dourish's paper. Contrast their study with other shorter term studies of video conferencing."

August 2000