visual display of data brad mcmillen evaluation and research department
TRANSCRIPT
![Page 1: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/1.jpg)
Visual Display of Data
Brad McMillenEvaluation and Research Department
![Page 2: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/2.jpg)
Things to Consider
Choices:• Text• Tables• Charts/Graphs
What do you want to say?
Who are you saying it to?
What is the most concise way to say it?
![Page 3: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/3.jpg)
Taken from http://www.cdc.gov/nccdphp/dnpa/obesity/trend/maps/index.htm
Example
![Page 4: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/4.jpg)
Text
Between 1996-97 and 2006-07, the number of students enrolled in WCPSS grew by 50%. During
that same time, however, the number taking AP exams increased by 175% and the number of exams taken increased 195%.
![Page 5: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/5.jpg)
Table
Simple, but effective Can be one or two-dimensional (rows and/or
columns) Good for displaying smaller (or larger!) amounts of
data Layout of table can determine how the audience
consumes the data
![Page 6: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/6.jpg)
![Page 7: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/7.jpg)
![Page 8: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/8.jpg)
Bar/Column Chart
Usually used to show changes over time or comparisons among groups/categories
Clustered Column - compares values across categories
Stacked Column - shows the relationship of individual items to the whole
100% Stacked Column - compares the percentage each value contributes to a total across categories
![Page 9: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/9.jpg)
![Page 10: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/10.jpg)
Percent of Students Eligible for Free or Reduced Price Lunch, 2006-07
9.8% 8.4% 7.1%
51.1%
41.7%
31.0%
0.0%
20.0%
40.0%
60.0%
80.0%
100.0%
Elem MS HS
Grade Span
Pe
rce
nt
of
AD
M
Free
Reduced
![Page 11: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/11.jpg)
![Page 12: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/12.jpg)
Line Chart
Shows changes or trends over time Either for a single category or multiple
Horizontal axis usually is a time measurement
Usually with equal intervals of time
![Page 13: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/13.jpg)
![Page 14: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/14.jpg)
Pie Chart
Shows the proportionality across categories as they relate to a whole
Pie - displays the contribution of each value to a total Exploded Pie - displays the contribution of each value to a
total while emphasizing individual values
![Page 15: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/15.jpg)
![Page 16: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/16.jpg)
Percent of Students ProficientGeometry EOC Test, 2006-07
13%
17% 57%
13%
Level ILevel IILevel IIILevel IV
![Page 17: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/17.jpg)
Scatterplot
Shows pairs of values plotted according to X-Y coordinates
• Good for illustrating the relationship between two variables
• Good for displaying the amount of “spread” in the data
![Page 18: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/18.jpg)
50
60
70
80
90
100
80 85 90 95 100
Attendance Rate
Per
cent
Pro
fici
ent
![Page 19: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/19.jpg)
State Math Scores and Students' TV Viewing Habits
AL
AZ
ARCA
CO
CT
DE
DC
FLGA HI
IDIN
IA
KY
LA
ME
MD
MA MI
MN
MS
MO
NENH
NJ
NM
NYNC
ND
OHOK
PA
RI
SCTN
TX
UT
VA
WV
WI
WY
230
240
250
260
270
280
290
0 5 10 15 20 25 30
% Students watching TV 6 hrs+ per day
1992
Sta
te 8
th-g
rade
NA
EP
Mat
h S
core
source: National Center for Educational Statistics, 1994
![Page 20: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/20.jpg)
Histogram
• A chart (usually a simple column chart) that takes a collection of measurements and plots the number of measurements (called the frequency) that fall within each of several intervals
![Page 21: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/21.jpg)
Distribution of EOG Scale Scores
0
10
20
30
40
50
60
239
241
243
245
247
249
251
253
255
257
259
261
263
265
267
269
271
273
275
![Page 22: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/22.jpg)
Principles of Good Graphics
• Clearly labeled
• Not too “busy”
• Readable font
• Quickly draws attention to the desired point
• Reasonable choice of metric and precision
![Page 23: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/23.jpg)
![Page 24: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/24.jpg)
# Students by Ethnicity
0
10000
20000
30000
40000
2003 2004 2005 2006
Asian
African-American
Native American
White
Multiracial
Hispanic/Latino
![Page 25: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/25.jpg)
Report Cards
![Page 26: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/26.jpg)
Taken from http://www.cdc.gov/nccdphp/dnpa/obesity/trend/maps/index.htm
Example
![Page 27: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/27.jpg)
Sources of Deception in Graphics
• Labels not specific
• Scaling of axes is inappropriate
• Choice of chart type “leads” reader to the wrong conclusions
• Ignores important contextual factors
• Too much stuff – obscures the point
![Page 28: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/28.jpg)
![Page 29: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/29.jpg)
Taken from http://mediamatters.org/items/200503220005
![Page 30: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/30.jpg)
Taken from Tufte, E. (1983). The Visual Display of Quantitative Information. Cheshire, CT: Graphics Press.
![Page 31: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/31.jpg)
![Page 32: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/32.jpg)
30
40
50
60
70
80
90
100
WCPSS 75 77 79
NC 74 71 71
USA 49 48 48
2005 2006 2007
WCPSS
USA
NC
![Page 33: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/33.jpg)
EOG Mathematics Proficiency, Grades 3-8
84.589.0 89.5 88.3
64.1
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
100.0
2001-02 2002-03 2003-04 2004-05 2005-06
![Page 34: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/34.jpg)
![Page 35: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/35.jpg)
![Page 36: Visual Display of Data Brad McMillen Evaluation and Research Department](https://reader035.vdocuments.mx/reader035/viewer/2022062408/56649f115503460f94c24b69/html5/thumbnails/36.jpg)
Brad McMillen
Evaluation and Research Department
Wake County Public Schools
(919) 850-1903