Introduction to HCI Methods and the Design of Studies Guest Lecturer: - - PowerPoint PPT Presentation

introduction to hci methods and the design of studies
SMART_READER_LITE
LIVE PREVIEW

Introduction to HCI Methods and the Design of Studies Guest Lecturer: - - PowerPoint PPT Presentation

Introduction to HCI Methods and the Design of Studies Guest Lecturer: Marshini Chetty Slides amended from Lorrie Cranor and Blase Ur 1 Who am I? Marshini Chetty Marshini C hetty, Assistant Prof Assistant Professor iSchool, UMIACS, CS College of


slide-1
SLIDE 1

1

Introduction to HCI Methods and the Design of Studies

Guest Lecturer: Marshini Chetty Slides amended from Lorrie Cranor and Blase Ur

slide-2
SLIDE 2

2

Marshini C hetty, Assistant Prof iSchool, UMIACS, CS

Who am I?

Marshini Chetty

Assistant Professor College of Information Studies marshini@umd.edu

slide-3
SLIDE 3

3

slide-4
SLIDE 4

4

www.cs.umd.edu/hcil

slide-5
SLIDE 5

5

Who are you?

  • Name, rank, serial number
  • Program at UMD?
  • Why did you sign up for this course?
slide-6
SLIDE 6

6

Human Computer Interaction

HUMAN

slide-7
SLIDE 7

7

Human Computer Interaction

Technology

slide-8
SLIDE 8

8

slide-9
SLIDE 9

9

Human-Computer Interaction (HCI)

  • You are not the user! You know too much!
  • Think about the user throughout design
  • Involve the user
slide-10
SLIDE 10

10

Human-Computer Interaction (HCI)

slide-11
SLIDE 11

11

Examples of bad design


slide-12
SLIDE 12

12

slide-13
SLIDE 13

13

slide-14
SLIDE 14

14

slide-15
SLIDE 15

15

What is usable?

  • Intuitive / obvious
  • Efficient
  • Learnable
  • Memorable
  • Few errors
  • Not annoying
  • Status transparent

Image ¡from ¡h+p://www.xkcd.com ¡

slide-16
SLIDE 16

16

Difficulties

  • Many systems and platforms
  • Users are different from one another
  • Required standards (or no standards)
  • Documentation won’t necessarily be read
  • Performance
  • Legal / time pressures
  • Social and external factors
slide-17
SLIDE 17

17

Determine use cases and goals

  • What are the concrete tasks users should

be able to accomplish?

– Based on understanding of users!

  • Set realistic metrics
slide-18
SLIDE 18

18

Personas (example)

Name: Patricia Age: 31 Occupation: Sales Manager, IKEA Store Hobbies: Painting Fitness/biking Taking son Devon to the park Likes: Emailing friends & family Surprises for her husband Talking on cell phone with friends Top 40 radio stations Eating Thai food Going to sleep late Dislikes: Slow service at checkout lines Smokers

slide-19
SLIDE 19

19

Iterative prototyping is crucial!

High-fidelity, “Wizard of Oz,” low-fidelity

slide-20
SLIDE 20

20

Iterative prototyping is crucial!

slide-21
SLIDE 21

21

Iterative prototyping is crucial!

slide-22
SLIDE 22

22

Usability prototyping for websites

Site Maps Storyboards Schematics Mock-ups

slide-23
SLIDE 23

23

Paper prototypes

  • Don’t overthink. Just make it.
  • Draw a frame on a piece of paper
  • Sketch anything that appears on a card
  • Make all menus, etc.
  • Redesign based on feedback
  • “Think aloud”
slide-24
SLIDE 24

24

Think aloud example

  • Download and install software that lets you

encrypt your email

– Verify that it is installed

  • Things you can ask:

– What are you thinking now? – What do you expect to happen if you do X? – How did you decide to do that?

slide-25
SLIDE 25

25

Paper prototype example (in groups)

  • Draw a paper prototype of a tool to encrypt

emails sent on Gmail

– First step: Identify two tasks that you want to make sure are usable

slide-26
SLIDE 26

26

Usability of Fruit

  • https://www.youtube.com/watch?

v=3Qg80qTfzgU

slide-27
SLIDE 27

27

Research studies: purpose and goals

  • What are you hoping to learn?
  • What are your hypotheses?

– Sometimes listed explicitly in a paper

  • What are your metrics for success?

– More secure, quicker to use, more fun, etc.

  • What are you comparing to?
  • What data might be helpful?
slide-28
SLIDE 28

28

Broad types of studies

  • Field study
  • Laboratory study
  • Online study
  • (Measurement study)
slide-29
SLIDE 29

29

Quantitative vs. Qualitative

  • Quantitative: you have numbers (timing

data, ratings of awesomeness)

  • Qualitative: you have non-numerical data

(thoughts, opinions, types of errors)

slide-30
SLIDE 30

30

Types of studies

  • Find out what people want:

– Contextual inquiry – Interviews – Focus groups – Surveys – Diary study (prompt people)

  • Find out what/how people think:

– Interviews – Surveys

slide-31
SLIDE 31

31

Types of studies

  • Expert evaluation of usability:

– Cognitive walkthrough – Heuristic evaluation

  • Usability test:

– Laboratory (“think aloud”) – Online study – Log analysis

slide-32
SLIDE 32

32

Types of studies

  • Controlled experiments to test causation:

– e.g., A/B testing

  • Role-playing
  • Experiments in the field
  • Varying different conditions

– Full-factorial design or not

slide-33
SLIDE 33

33

Data to collect during experiments

  • Independent vs. dependent variables
  • Performance (time, success rate, errors)
  • Opinions and attitudes
  • Audio recording, screen capture, video,

mouse movements, keystrokes

  • Formative (initial) vs. summative (validate)
slide-34
SLIDE 34

34

Even more data to collect

  • Demographics

– Age, gender, technical background, income, education, occupation, location, disabilities, first language, privacy attitudes, etc.

  • Open-ended questions
  • Preferences and attitudes

Please respond to the following statements: *This user interface was difficult to understand 1- Strongly disagree 2- Disagree 3- Neutral 4- Agree 5- Strongly agree *This tool was fun to use 1- Strongly disagree 2- Disagree 3- Neutral 4- Agree 5- Strongly agree

slide-35
SLIDE 35

35

Logistics for a study

  • How many participants?

– Statistical power – Time, budget, participants’ time

  • What kind of participants?

– Skills, background, interests – Their motivations – Often not a “representative sample”

  • What do you need to build, if anything?

– Prototype fidelity

slide-36
SLIDE 36

36

Study designs

  • Between subjects

– Each participant tests 1 version of the system – You compare these groups – Groups should be similar (verify!)

  • Within subjects

– Every participant tests everything – Very important to randomize order! – Fewer participants

slide-37
SLIDE 37

37

That’s it for now…

  • Find out more about my lab…

– http://netchi.umd.edu – http://marshini.net – Get in touch…. – marshini@umd.edu