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Ethics in data designstat/engl 332
Ethical issues are often very subtle—but may
still have consequences!
• May be interpreted differently by some readers
• May only affect some readers
• May not be readily apparent to all readers
Addressing ethical issues in our designs
• Apply Tufte’s “Lie Factor”
• Explain why you’re emphasizing certain data
• Consider “what’s missing” in your display
• Always put yourself in your readers’ shoes
when making design decisions (golden rule)
• Get feedback from your readers!
update …
• there is no comparable table for graduate students
• other sources we might be able to use:
• http://admissions.uiowa.edu/finances/
estimated-costs-attendance
• http://uni.edu/tuition/2013-2014-undergraduate-tuition-fees
• http://admissions.illinois.edu/cost/tuition.html
TablesWays to present information in tabular form
stat/engl 332
Purpose
• Data may be stored in a raw, more precise form, which may not be easily digested by a reader.
• Tables process the raw data, communicating information in an organized manner.
• Good tables should be easy to read across rows and down columns, easy to understand, and easy to refer to in the text of your report. They should also include only relevant data from your results.
Example of a table
45
45
Enrollment by Race/Ethnicity1Fall Semester Headcount and Percent by Level
1 Race/ethnicity groups include U.S. citizens, immigrants, and refugees only; White includes students who do not identify race/ethnicity affi liation. International includes non-resident alien students regardless of race/ethnicity affi liation.
Offi ce of Institutional Research (Source: Offi ce of the Registrar)
–––––2001––––– –––––2002––––– –––––2003––––– –––––2004––––– –––––2005–––––LEVEL AND RACE/ETHNICITY NUMBER % NUMBER % NUMBER % NUMBER % NUMBER %Undergraduate 23,060 22,999 22,230 21,354 20,732
African American 604 2.6% 640 2.8% 601 2.7% 594 2.8% 603 2.9%American Indian/Alaskan Native 69 0.3% 72 0.3% 66 0.3% 68 0.3% 61 0.3%Asian/Pacific Islander 598 2.6% 628 2.7% 661 3.0% 687 3.2% 692 3.3%Hispanic 423 1.8% 440 1.9% 476 2.1% 445 2.1% 470 2.3%White 20,235 87.7% 20,166 87.7% 19,555 88.0% 18,819 88.1% 18,261 88.1%International 1,131 4.9% 1,053 4.6% 871 3.9% 741 3.5% 645 3.1%
1st Professional 400 400 409 408 431African American 1 0.3% 1 0.3% 1 0.2% 0 0.0% 1 0.2%American Indian/Alaskan Native 2 0.5% 1 0.3% 1 0.2% 1 0.2% 0 0.0%Asian/Pacific Islander 4 1.0% 5 1.3% 4 1.0% 6 1.5% 4 0.9%Hispanic 1 0.3% 1 0.3% 0 0.0% 1 0.2% 2 0.5%White 390 97.5% 389 97.3% 399 97.6% 397 97.3% 422 97.9%International 2 0.5% 3 0.8% 4 1.0% 3 0.7% 2 0.5%
Graduate 4,363 4,499 4,741 4,618 4,578African American 101 2.3% 106 2.4% 120 2.5% 117 2.5% 124 2.7%American Indian/Alaskan Native 8 0.2% 9 0.2% 11 0.2% 10 0.2% 20 0.4%Asian/Pacific Islander 69 1.6% 74 1.6% 69 1.5% 55 1.2% 72 1.6%Hispanic 63 1.4% 62 1.4% 72 1.5% 71 1.5% 74 1.6%White 2,683 61.5% 2,724 60.5% 2,872 60.6% 2,814 60.9% 2,827 61.8%International 1,439 33.0% 1,524 33.9% 1,597 33.7% 1,551 33.6% 1,461 31.9%
Total 27,823 27,898 27,380 26,380 25,741African American 706 2.5% 747 2.7% 722 2.6% 711 2.7% 728 2.8%American Indian/Alaskan Native 79 0.3% 82 0.3% 78 0.3% 79 0.3% 81 0.3%Asian/Pacific Islander 671 2.4% 707 2.5% 734 2.7% 748 2.8% 768 3.0%Hispanic 487 1.8% 503 1.8% 548 2.0% 517 2.0% 546 2.1%White 23,308 83.8% 23,279 83.4% 22,826 83.4% 22,030 83.5% 21,510 83.6%International 2,572 9.2% 2,580 9.2% 2,472 9.0% 2,295 8.7% 2,108 8.2%
Enrollment by Race/Ethnicity1Fall Semester Headcount and Percent by Level
1 Race/ethnicity groups include U.S. citizens, immigrants, and refugees only; White includes students who do not identify race/ethnicity affi liation. International includes non-resident alien students regardless of race/ethnicity affi liation.
Offi ce of Institutional Research (Source: Offi ce of the Registrar)
–––––2001––––– –––––2002––––– –––––2003––––– –––––2004––––– –––––2005–––––LEVEL AND RACE/ETHNICITY NUMBER % NUMBER % NUMBER % NUMBER % NUMBER %Undergraduate 23,060 22,999 22,230 21,354 20,732
African American 604 2.6% 640 2.8% 601 2.7% 594 2.8% 603 2.9%American Indian/Alaskan Native 69 0.3% 72 0.3% 66 0.3% 68 0.3% 61 0.3%Asian/Pacific Islander 598 2.6% 628 2.7% 661 3.0% 687 3.2% 692 3.3%Hispanic 423 1.8% 440 1.9% 476 2.1% 445 2.1% 470 2.3%White 20,235 87.7% 20,166 87.7% 19,555 88.0% 18,819 88.1% 18,261 88.1%International 1,131 4.9% 1,053 4.6% 871 3.9% 741 3.5% 645 3.1%
1st Professional 400 400 409 408 431African American 1 0.3% 1 0.3% 1 0.2% 0 0.0% 1 0.2%American Indian/Alaskan Native 2 0.5% 1 0.3% 1 0.2% 1 0.2% 0 0.0%Asian/Pacific Islander 4 1.0% 5 1.3% 4 1.0% 6 1.5% 4 0.9%Hispanic 1 0.3% 1 0.3% 0 0.0% 1 0.2% 2 0.5%White 390 97.5% 389 97.3% 399 97.6% 397 97.3% 422 97.9%International 2 0.5% 3 0.8% 4 1.0% 3 0.7% 2 0.5%
Graduate 4,363 4,499 4,741 4,618 4,578African American 101 2.3% 106 2.4% 120 2.5% 117 2.5% 124 2.7%American Indian/Alaskan Native 8 0.2% 9 0.2% 11 0.2% 10 0.2% 20 0.4%Asian/Pacific Islander 69 1.6% 74 1.6% 69 1.5% 55 1.2% 72 1.6%Hispanic 63 1.4% 62 1.4% 72 1.5% 71 1.5% 74 1.6%White 2,683 61.5% 2,724 60.5% 2,872 60.6% 2,814 60.9% 2,827 61.8%International 1,439 33.0% 1,524 33.9% 1,597 33.7% 1,551 33.6% 1,461 31.9%
Total 27,823 27,898 27,380 26,380 25,741African American 706 2.5% 747 2.7% 722 2.6% 711 2.7% 728 2.8%American Indian/Alaskan Native 79 0.3% 82 0.3% 78 0.3% 79 0.3% 81 0.3%Asian/Pacific Islander 671 2.4% 707 2.5% 734 2.7% 748 2.8% 768 3.0%Hispanic 487 1.8% 503 1.8% 548 2.0% 517 2.0% 546 2.1%White 23,308 83.8% 23,279 83.4% 22,826 83.4% 22,030 83.5% 21,510 83.6%International 2,572 9.2% 2,580 9.2% 2,472 9.0% 2,295 8.7% 2,108 8.2%
Fact Book 2005-2006
Example: ISU Factbook
Title
Data cells
Explanatory notes
SourceRow headings and subheadings
Column headings
Divider
Table conventions
Stub
Rounding
Sans serif font
Footnotes
Complex headings
Getting the eye across the row
Repetition of text or symbols
Spanners
Emphasis on key data
Other issues in table design
Elements of a table• Title: The title provides a brief description of the
contents. It should be concise, and include key elements, such as groups, variables, etc.
• Headings and sub-headings: Establish order to the information. Units of measurement should be included here.
• Table body: Actual data, percentages, frequencies.
• Marginals:Totals on rows, and or columns to
assist making comparisons.
• Dividers: Lines or spaces that make the material
more digestible - avoid vertical lines!
• Table notes: Clarify specific parts of the table.
Rules for displayTitle What goes
in columns? Marginal
What goes in rows? Ordering
Zero out
small
numbers?
Alignment
*Rounding* 3.141593 to
3.14Spacing and
layout
Alignment
MarginalSummary/Caption Marginal
Rows or columnsDogs Cats Fish Birds Other820 700 350 320 615
OR
Dogs 820
Cats 700
Fish 350
Birds 320
Other 615
Comparing numbers is easier down a column
than across a row.
Rounding
OR
A lot of numbers to
read.
Less numbers to digest, easier to
focus on the trends
What’s the message being communicated by
the table?
A Historical Example
John Graunt
Development of the idea that vital statistics (records of christenings and burials in London) could be used to construct life tables. The birth of demographic statistics.
Graunt’s tables of casualties
http://www.ac.wwu.edu/~stephan/Graunt/chart.html
http://www.edstephan.org/Graunt/chart.html
Graunt’s tables of casualties
From the table of casualties:
• what was the most common cause of death?
• which cause of death was dramatically
different in 1647 than other years?
• which year was the worst year for casualties?
Re-worked Graunt’s table of casualties
From the table of casualties:
• what was the most common cause of death?
• which cause of death was dramatically
different in 1647 than other years?
• which year was the worst year for casualties?
How has this table been improved?
Alignment
Number of digits
standardized
Removal of grid lines, raising the
prominence of the table body
What’s wrong with this table?
Unordered.
Different types of products.
Numbers centered, right justified.
Headers not clearly distinguished from
body of table.
Re-worked table
• Items grouped into larger categories: proteins, carbohydrates, vegetables
• Dividers used
• Titles improvedNot fixed: Order within each food group.
How would you order it?
RECAP: Rules for display
1. Comparing numbers is easier down a column.
2. Sort rows and columns.
3. Round numbers.
4. Add marginal summaries.
5. Use space to help reader digest material, eg every 5 rows.
6. Align columns of numbers.
7. Title.
8. Caption.
9. Legend.
Tables to plotsHow would you convert this table to a graphic?
02/15/2006 13: 38 7039931700 EMU STATISTICS PAGE 82/03
Chapter 2
Table 2-8. Environmental Distribution of TRIRalaaeas and Tranefera by State. 1987Adjustad Data.
TexasLouisianaOhioFloridaTennessee
MichiganIllinoisIndianaUtahPennsylvania
CaliforniaVirginiaNew YorkMissouriNew Jersey
MississippiGeorgiaNorth CarolinaAlabamaKansas
KentuckyWisconsinSouth CarolinaArkansasArizona
MassachusettsWest VirginiaMinnesotaConneticutOklahoma
IowaMarylandWashingtonAlaskaOregon
MontanaWyomingNew MexicoColoradoMaine
NebraskaNew HampshireIdahoDelawareRhode Island
HawaiiSouth DakotaVermontNevadaNorth Dakota
0 4 8
Total
0 1 2
Air
0 1 2
Transfer
0 1 2 3 4 5
Underground
0 1 2
Land
0 1 2
Sewage
0 1 2
Water
TRI Releases And Transfers For 1987
Totals By State and Distribution Class
Grand Total = 7 Billion Pounds
STATE
(Reduced Scale)
Units: 100 Million Pounds
August 94 Statistical Computing & Statistical Graphics Newsletter 13
Interactive tables for exploring data
• Pivot tables: rearranging, aggregating, marginal summaries calculated on the fly.
• Table lens: Explore tables visually: sorting, barcharts, probing.
(Rao, Card 1994)
Sources
• Ehrenberg (1977) The Rudiments of Numeracy JRSS(A), 140(3):277-297
• Wainer (1997) Improving Tabular Displays, JEBS, 22(1): 1-30
• Spence (2001) Information Visualization
• Table Lens
http://www.ramanarao.com/papers/tablelens-chi94.pdf
• http://www.ncsu.edu/labwrite/res/gh/gh-tables.html