Getting Algorithm Visualizations into the Classroom

1
Getting Algorithm Visualizationsinto the
Classroom

• Clifford A. Shaffer
• Monika Akbar
• Alexander Joel D. Alon
• Michael Stewart
• Stephen H. Edwards
• Department of Computer Science
• Virginia Tech
• Blacksburg, VA 24061

2
AVs

• AVs have high faculty and student favorability
  ratings

3
AVs The Problem

• AVs have high faculty and student favorability
  ratings
• But AV use in courses does not match the
  favorability ratings

4
Informal Survey Results

• Warning Self-selected responders

5
Informal Survey Results

• Warning Self-selected responders
• Are AVs useful?
• Strongly Agree 12
• Agree 17
• Neutral 1

6
Informal Survey Results

• Warning Self-selected responders
• Are AVs useful?
• Strongly Agree 12
• Agree 17
• Neutral 1
• A (bare) majority indicated that they used some
  sort of visualization with class

7
Survey Impediments to Use

• Lack of knowledge/time to find good AVs 13

8
Survey Impediments to Use

• Lack of knowledge/time to find good AVs 13
• Time to make good AVs 2
• Difficulty integrating in class 9
• Lack of time within class constraints 2
• Uncertainty about quality outcomes 1
• Content not relevant to my classes 1

9
Overcoming Impediments

• Reassurance about what AVs are good
• Ideas on how to use AVs
• Reassurance about how a given AV can be used
  successfully in class
• Ability to connect to developers

10
Community Solutions

• http//algoviz.org/
• Build a community of users/developers
• Better disseminate best practice information
• Project Support
• NSF CCLI grant
• NSF NSDL grant
• Connections to NSDL/Ensemble project

11
AlgoViz.org
12
AlgoViz.org

• A collection of links to over 500AVs
• With rating and review information

13
AlgoViz.org

• A collection of links to over 500AVs
• With rating and review information
• Annotated bibliography over 500 papers

14
AlgoViz.org

• A collection of links to over 500AVs
• With rating and review information
• Annotated bibliography over 500 papers
• Field reports, forums Community input

15
AlgoViz.org

• A collection of links to over 500AVs
• With rating and review information
• Annotated bibliography over 500 papers
• Field reports, forums Community input
• AlgoViz news and information

16
AlgoViz.org

• A collection of links to over 500AVs
• With rating and review information
• Annotated bibliography over 500 papers
• Field reports, forums Community input
• AlgoViz news and information
• Guides and information for developers

17
AlgoViz.org

• A collection of links to over 500AVs
• With rating and review information
• Annotated bibliography over 500 papers
• Field reports, forums Community input
• AlgoViz news and information
• Guides and information for developers
• OpenAlgoViz

18
Phase I The Passive Side

• What problem do we solve here?
• AlgoViz addresses instructors reported need for
  information

19
Phase I The Passive Side

• What problem do we solve here?
• AlgoViz addresses instructors reported need for
  information
• Nearly done!

20
AlgoViz Usage Statistics
21
Phase II The Active Side

• Key problem How to help instructors through the
  impediments to using AVs
• We identified community as a solution
• How do we build an online educational community?

22
New Paradigm for Digital Library
23
New Paradigm for Digital Library

• Create a new model of dissemination to lower
  barriers to access
• Move away from the digital library model of
  users coming to collections

24
New Paradigm for Digital Library

• Create a new model of dissemination to lower
  barriers to access
• Move away from the digital library model of
  users coming to collections
• Focus on community-driven content development
• Discussion, review, ratings
• Think Amazon, but we have critical mass issues

25
Community Value Added

• Catalog entry ratings
• Catalog entry reviews
• Field reports
• Forum discussions
• Interactions with developers

26
Community Building AlgoViz Awards

• Exemplars of good AVs

27
Community Building AlgoViz Awards

• Exemplars of good AVs
• Solicited votes from the public on a slate of
  nominees
• 2010 Six winners
• Hall of Fame 61
• Sorting out Sorting

28
Community Building AlgoViz Awards

• Exemplars of good AVs
• Solicited votes from the public on a slate of
  nominees
• 2010 Six winners
• Hall of Fame 61
• Sorting out Sorting
• 2011 Two winners
• Come to NSF showcase tomorrow
• 300pm Friday

29
Notification

• Connect to community by informing members of site
  changes
• News posts,
• New AVs, bibliography, field reports, forum posts

30
Notification

• Connect to community by informing members of site
  changes
• News posts,
• New AVs, bibliography, field reports, forum posts
• Email, FaceBook, Twitter, RSS feeds

31
Notification

• Connect to community by informing members of site
  changes
• News posts,
• New AVs, bibliography, field reports, forum posts
• Email, FaceBook, Twitter, RSS feeds
• Fine grained
• User control of information stream
• User profiles

32
Registration and Access (1)

• Site registration requirements deter users from
  participating
• Link spammers and other malicious entities can
  overwhelm a site

33
Registration and Access (1)

• Site registration requirements deter users from
  participating
• Link spammers and other malicious entities can
  overwhelm a site
• So we need a balance
• Minimum registration requirements possible

34
Registration and Access (1)

• Site registration requirements deter users from
  participating
• Link spammers and other malicious entities can
  overwhelm a site
• So we need a balance
• Minimum registration requirements possible
• Goals
• Link together a given users site activities
• Be able to block a user

35
Registration and Access (2)

• Solutions

36
Registration and Access (2)

• Solutions
• Allow unrestricted access to view

37
Registration and Access (2)

• Solutions
• Allow unrestricted access to view
• Minimize registration burden

38
Registration and Access (2)

• Solutions
• Allow unrestricted access to view
• Minimize registration burden
• FaceBook connect, etc.

39
Registration and Access (2)

• Solutions
• Allow unrestricted access to view
• Minimize registration burden
• FaceBook connect, etc.
• Initially moderate, then declare user to be
  trusted

40
Lessons Learned
41
Lessons Learned

• Building site infrastructure and collection is
  relatively easy
• Developers are motivated to provide information

42
Lessons Learned

• Building site infrastructure and collection is
  relatively easy
• Developers are motivated to provide information
• Building community infrastructure is relatively
  easy

43
Lessons Learned

• Building site infrastructure and collection is
  relatively easy
• Developers are motivated to provide information
• Building community infrastructure is relatively
  easy
• Building community is hard

44
You can help!

• We need field reports!
• Can be quite informal, just post a couple
  paragraphs on your classroom experience with
  using an AV
• Ratings/reviews of Avs
• Discussion (forums)
• Thank you!

45
You can help!
46
You can help!

• We need field reports!
• Can be quite informal, just post a couple
  paragraphs on your classroom experience with
  using an AV

47
You can help!

• We need field reports!
• Can be quite informal, just post a couple
  paragraphs on your classroom experience with
  using an AV
• Ratings/reviews of Avs
• Discussion (forums)

48
You can help!

• We need field reports!
• Can be quite informal, just post a couple
  paragraphs on your classroom experience with
  using an AV
• Ratings/reviews of Avs
• Discussion (forums)
• Thank you!