Overview
Data & Data Visualization
R Resources
References
Data Visualization using R
Damian W. Betebenner
National Center for the Improvement of Educational Assessment
Dover, NH
NERA Training Session
Trumbull, Connecticut October 27th, 2016
Damian W. Betebenner Data Visualization using R
Overview
Data & Data Visualization
About the R Software
R Resources
References
Purpose of today’s session
To learn about R and its capabilities for visualizing data.
To provide participants with a comprehensive list of resources for
producing their own data visualizations.
To demonstrate the power of programatic drawing over WYSIWYG
drawing.
To inspire participants to develop their own customized
visualizations and push the envelope for what is possible
Damian W. Betebenner Data Visualization using R
Overview
Data & Data Visualization
About the R Software
R Resources
References
About Me
Dr. Damian Betebenner, PhD
Senior Associate at the Center for Assessment (NCIEA).
Developed student growth percentiles and percentile growth
trajectories to help states and educational associations employ
student growth in decision
making [Betebenner, 2008, Betebenner, 2009].
In the process of refining and sharing these techniques with
other states including Colorado, Massachusetts, Arizona,
Indiana, and 15 other states in various stages of
investigation/adoption.
Interested in the rise of the data sciences/scientist: Data
analysis and data visualization and their use within education.
Began using R in 1998.
Damian W. Betebenner Data Visualization using R
Overview
Data & Data Visualization
About the R Software
R Resources
References
About the R Software
R is an GNU open source, free, statistical software environment
(package/language) that is available for source compilation or in
pre-compiled binary form for numerous operating systems.
R can be downloaded from CRAN (Comprehensive R Archive
Network) http://cran.r-project.org/
The R language has become a de facto standard among
statisticians for the development of statistical software.
The philosophy behind R/S (John Chambers): “To Turn Ideas into
Software Quickly and Faithfully” [Chambers, 2000, p. v]
Damian W. Betebenner Data Visualization using R
Overview
Data & Data Visualization
About the R Software
R Resources
References
About the R Software
Daryl Pregibon, Google
R is really important to the point that it’s hard to overvalue it.
R had a recent New York Times article written about it
http://www.nytimes.com/2009/01/07/technology/
business-computing/07program.html.
A particular strength of R is its data visualization capabilities
The greatest strength of R (in my humble opinion) is the IMMENSE
amount of code available online to learn from. Learn from the
masters.
This training session will introduce users to data visualization using
R as well as the resources available to continue their explorations.
Damian W. Betebenner Data Visualization using R
Overview
Data & Data Visualization Data
R Resources Data Visualization
References
About Data
Rutherford D. Roger
We are drowning in information [data] and starving for knowledge [in-
formation].
The Economist, February 27th, 2010, devoted a special issue to
“The Data Deluge”.
In 2008, 1,200 exabytes (1.2 ZB) of digital data was created (n.b.,
giga, tera, peta, exa, zetta, yotta).
Compound annual increase of data at 60%.
Petabyte level computing is reaching commodity levels with Amazon
EC2/S3 offering specials for petabyte scale projects.
Damian W. Betebenner Data Visualization using R
Overview
Data & Data Visualization Data
R Resources Data Visualization
References
About Data
Hal Varian, Chief Economist, Google
A new kind of professional has emerged, the data scientist, who
combines the skills of a software programmer, statistician, and story-
teller/artist to extract nuggets of gold hidden under mountains of data.
The job of the data scientist will become the sexiest around. Data are
widely available; what is scarce is the ability to extract wisdom from
them.
The Data doesn’t speak for itself. The data can tell a thousand stories.
Transforming data into information and ultimately into knowledge
requires a broad range of expertise (i.e., the emerging data scientist).
Goal: The right data to the right people at the right time in the right
format!
To reach this goal subject matter experts MUST work more closely
with IT specialists, ensuring the right stories are told.
Damian W. Betebenner Data Visualization using R
Overview
Data & Data Visualization Data
R Resources Data Visualization
References
About Data Visualization
Data visualization leverages the immense capacity of the human eye
to extract patterns from visual stimuli.
Communicating with data is a form of storytelling. Visualization
allows the storyteller to communicate more effectively and engage
the user in more complicated stories.
Color, pattern, and symbols can be combined to communicate highly
complicated stories that, without pictures, are difficult even for
experts to follow.
As such, data visualization, as communication, is a form of teaching.
Damian W. Betebenner Data Visualization using R
Overview
Data & Data Visualization Data
R Resources Data Visualization
References
About Programmatic Drawing
Byron Ellis via Twitter
[R] is for making new things. Point and click is for redoing old things.
Almost all graphical programs (especially those incorporated in
statistical analysis packages) rely upon WYSIWYG interface.
WYSIWYG pros: Easy to learn. WYSIWYG cons: Limited ability to
customize.
Because of constrained options, WYSIWYG interfaces both dictate
and limit the stories you can tell with your data.
Programming your drawings (i.e., programatic drawing) allows for
unlimited possibilities, constrained only by the creator’s imagination.
Damian W. Betebenner Data Visualization using R
DEMONSTRATION: 2015−2016 Mathematics
Norm & Criterion Referenced Growth & Achievement
Percentile Growth Trajectory
2015−2016 Achievement Percentile
Scale Score
SGP trajectories for a 3rd grade student starting from the Level 1/Level 2 cut.
Grade 3 Grade 4 Grade 5 Grade 6 Grade 7 Grade 8 Grade 9 Grade 10
DEMONSTRATION: 2015−2016 Mathematics
Norm & Criterion Referenced Growth & Achievement
Percentile Growth Trajectory
2015−2016 Achievement Percentile
Scale Score
SGP trajectories for a 3rd grade student starting from the Level 1/Level 2 cut.
Grade 3 Grade 4 Grade 5 Grade 6 Grade 7 Grade 8 Grade 9 Grade 10
Observed Percent Proficient = 10 % Observed Percent Proficient = 20 % Observed Percent Proficient = 30 %
Observed Percent Proficient = 40 % Observed Percent Proficient = 50 % Observed Percent Proficient = 60 %
Observed Percent Proficient = 70 % Observed Percent Proficient = 80 % Observed Percent Proficient = 90 %
Bias in Observed Percent Proficient (Observed − True)
Observed under−estimates true Observed over−estimates true
Advanced Reading
Move Up
Achievement
● Target
DEMO Reading
● Scale Score
Keep Up
Catch Up ● Target
Proficient Target ●
● Growth
Level Percentiles
● Very High 81st − 99th
High 61st − 80th
Part Proficient Typical 40th − 60th
Low 20th − 39th
Very Low 1st − 19th
Unsatisfactory
Grade 3 Grade 4 Grade 5 Grade 6 Grade 7
Scale Score 449 533 579 602
Achievement Level
Achievement Target
Unsatisfactory Part Proficient Part Proficient Proficient
Proficient (592) Proficient (620)/Advanced (661)
Achievement
Growth Percentile 69 85 74
Growth Level
Growth Target
High Very High High
Catch Up (60) Keep Up (76)/Move Up (99)
Growth
Billy Gonzales North End Middle School
How to interpret this student
growth & achievement report Mathematics
Advanced
Achievement
● Catch
Target
Up
DEMO ● DEMO Mathematics
● Catch Up ●●
Target ●● Scale Score
Scale Score ● ●
Growth
Proficient ● Level Percentiles
DEMO Very High 81st − 99th
Achievement High 61st − 80th
Part Proficient
Levels Typical 40th − 60th
Low 20th − 39th
Unsatisfactory Very Low 1st − 19th
Student
Grade 3 Grade 4 Grade 5 Grade 6 Grade 7
Growth 2012−2013 2013−2014 2014−2015 2015−2016 2016−2017
Percentile Scale Score 438 447 489 495
Achievement Level
Achievement Target
Proficient Part Proficient Part Proficient Part Proficient
Proficient (514) Proficient (547)
Achievement
Growth Percentile 18 64 44
Catch Up/Keep Up Growth Level Very Low High Typical
Growth
Move Up/Stay Up Growth Target Catch Up (70) Catch Up (82)
Targets
Suggested Uses
Advanced Reading
Move Up
Achievement
● Target
DEMO Reading
● Scale Score
● Review past growth to assess ●
Keep Up
student academic progress toward ●
Catch Up ●● Target
Proficient Target ●● Growth
DEMO achievement goals. ●
Level Percentiles
● Develop remediation or enrich−
● Very High 81st − 99th
ment plans based on rate of
High 61st − 80th
growth needed to reach higher
DEMO achievement levels. Part Proficient Typical 40th − 60th
Low 20th − 39th
● Identify the rate of progress ●
Very Low 1st − 19th
needed in order to reach or Unsatisfactory
maintain proficient status
Grade 3 Grade 4 Grade 5 Grade 6 Grade 7
on the DEMO next year. 2012−2013 2013−2014 2014−2015 2015−2016 2016−2017
Scale Score 449 533 579 602
Achievement Level
Achievement Target
Unsatisfactory Part Proficient Part Proficient Proficient
Proficient (592) Proficient (620)/Advanced (661)
Achievement
Growth Percentile 69 85 74
Growth Level
Growth Target
High Very High High
Catch Up (60) Keep Up (76)/Move Up (99)
Growth
For more information please visit the Student Growth Percentiles Package (SGP Package) at www.sgp.io or contact dbetebenner@nciea.org
Cooperatively developed by the SGP Package & the Center for Assessment, Inc. Distributed by the SGP Package.
District C: 2008 CSAP Math School Results
Student Growth versus Student Achievement by Percent Free/Reduced Lunch
School Percent
Higher Achievement Higher Achievement Free/Reduced Lunch
Lower Growth Higher Growth
Percent at/above Proficient in School
Less than 20 percent
● 20 to 40 percent
● 40 to 60 percent
● 60 to 80 percent
● More than 80 percent
School Size
50 Students
100 Students
200 Students
30 500 Students
1,000 Students
10 Lower Growth Higher Growth
Lower Achievement Lower Achievement
Median of Student Growth Percentiles in School
2009 Statewide Middle School Performance
Growth and Achievement MCAS Math by School Poverty
100 Higher Achievement Higher Achievement School Size
90 Lower Growth Higher Growth 50 Students
100 Students
X XX X XX 250 Students
80 X XXX XX XX X XX
X X X XXX X XX X X 500 Students
X X XXXX
2009 Percent at/above Proficient
X XX X X X
XX XX XXX X X XX
70 X XX XX XXX XX X X X X XX X X 1000 Students
XX X X
XXX XX X X
XXXX XXX X X X
XX XXX XXX X XX X X X
XX X X X
60 X X XX X X X XXXXX
X X X X X XX X
X XX X X XXX
X XXX
X XX X X X
X X X XX X XX X X School Percent
X X X X X XXX X X X
X X XX XX XXXX
X X Free/Reduced Lunch
50 XX X XXXX XXX
XXXXX X
XXX X X X X X
X XX XXXXX X XX X XXX XXX X X
XXX X
X XX
XX
● Less than 20 percent
40 XXXXXX XXXX X
XX X X
XX
XX X XX X
XX
XX X XXX X X
X ● 20 to 40 percent
XXX X X
30 XXX
XX X
X X ● 40 to 60 percent
X XX X X X
X X XXXX
XX X XX
● 60 to 80 percent
X X X XX
● More than 80 percent
X XX X
X XX X
Lower Growth X X X X XX Higher Growth
0 Lower Achievement
Lower Achievement X
2009 Median Student Growth Percentile
2009 Statewide Middle School Performance
Growth and Achievement MCAS Math by School Poverty
100 Higher Achievement Higher Achievement School Size
90 Lower Growth Higher Growth 50 Students
100 Students
250 Students
500 Students
2009 Percent at/above Proficient
70 1000 Students
School Percent
Free/Reduced Lunch
X XX ● Less than 20 percent
X ● 20 to 40 percent
XX X X
● 40 to 60 percent
X XXX
X ● 60 to 80 percent
X XX X X X
X X ● More than 80 percent
XX X
XX
Lower Growth X X X X XX Higher Growth
0 Lower Achievement
Lower Achievement
2009 Median Student Growth Percentile
Overview
Data & Data Visualization Online/Free
R Resources Books
References
So Many Amazing Resources: Free
Numerous help manuals installed when R is installed (Under the
Help dropdown menu in Windows)
One can download R and numerous resources at the CRAN
(Comprehensive R Archive Network)
http://cran.r-project.org/.
Click on the “Contributed” hyperlink at CRAN to access dozens of
free resources in many languages.
Most resources provide many nuggets of wisdom that proves to be
useful. Good places to start include:
John Maindonald’s Using R for Data Analysis and
Graphics–Introduction, Examples and Commentary
John Verzani’s Simple R
R has a very active listserve for R (R-help) that is easy to search
using Google and keywords.
Damian W. Betebenner Data Visualization using R
Overview
Data & Data Visualization Online/Free
R Resources Books
References
So Many Amazing Resources: Free
The R Graph Gallery. Great examples with source code:
http://addictedtor.free.fr/graphiques/.
Spatial Data and R. Great examples with source code
http://r-spatial.sourceforge.net/.
A four part online video tutorial for using ggplot
http://blog.revolution-computing.com/2010/03/
video-hadley-wickham-gives-a-short-course-on-graphics-with-r
html
Microsoft R Open (formerly Revolution R):
https://mran.microsoft.com/open/
Damian W. Betebenner Data Visualization using R
Overview
Data & Data Visualization Online/Free
R Resources Books
References
So Many Amazing Resources: Published Books
The Grid Graphics Package (and traditional graphics
overview) [Murrell, 2006]
Lattice Graphics Package: Depyan Sarkar [Sarkar, 2008].
ggplot Graphics Package: Hadley Wickham [Wickham, 2009].
Spatial Data Analysis and Visualization [Bivand et al., 2008].
Damian W. Betebenner Data Visualization using R
Overview
Data & Data Visualization Online/Free
R Resources Books
References
Inspiration
“A Thing of Beauty is a Joy Forever”
John Keats
Damian W. Betebenner Data Visualization using R
Overview
Data & Data Visualization
R Resources
References
References
Betebenner, D. W. (2008).
Toward a normative understanding of student growth.
In Ryan, K. E. and Shepard, L. A., editors, The Future of Test-Based
Educational Accountability, pages 155–170. Taylor & Francis, New
York.
Betebenner, D. W. (2009).
Norm- and criterion-referenced student growth.
Educational Measurement: Issues and Practice, 28(4):42–51.
Bivand, R. S., Pebesma, E. J., and Gòmez-Rubio, V. (2008).
Applied Spatial Data Analysis with R.
Springer, New York.
Chambers, J. M. (2000).
Programming with Data.
Springer, New York.
Murrell, P. (2006).
R Graphics.
Springer, New York.
Sarkar, D. (2008).
Lattice: Multivariate Data Visualization with R.
Springer, New York.
Wickham, H. (2009).
ggplot2: Elegant Graphics for Data Analysis.
Springer, New York.
Damian W. Betebenner Data Visualization using R
About this copy
Data Visualization using R — Northeastern Educational Research Association, October 2016.
This is an image-based copy of the original beamer slides; builds and animations are flattened.