Creating effective
tables and charts
Jane E. Miller, PhD
nd
The
The Chicago
Chicago Guide
Guide to
to Writing
Writing about
about Multivariate
Multivariate Analysis,
Analysis, 2
2nd edition.
edition.
Overview
•
•
•
•
•
•
Criteria for effective tables and charts
Guidelines for titles
Anatomy of a table
Anatomy of a chart
Examples
Practice writing sentences about table or chart
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Criteria for an effective
table or chart
• Self-contained
• Succinct
• Organized to coordinate with associated
narrative description
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Review: Information needed to
report a number
• W’s (context)
– When
– Where
– What
– Who
• Identity of each variable
– No “alphabet soup” acronyms!
– Meaningful words or phrases for each variable
• Units or categories for all variables shown
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
What does “self-contained” mean?
• Each table and chart in your work should be selfcontained.
• Without reference to the text, readers should be
able to understand:
– Purpose of that particular table or chart
– Context (W’s)
– Variables
– Units or categories for all variables
– Acronyms or symbols
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Test of “self-contained”
Population, number and percentage poor,
by age group, United States, 2002
Age group (years)
Number poor Total population
(1,000s)
(1,000s)
% poor
<18
12,133
72,653
16.7
18–64
18,861
177,934
10.6
3,576
34,385
10.4
34,570
284,972
12.1
65+
Total
• A reader unfamiliar with your data or study should be able to
point to any number in the table and be able to write a
complete, correct sentence about that number, based solely
on the information in that table and its notes.
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
What does “succinct” mean?
• Includes the information needed to address a
specific question or set of related questions.
• Reduce clutter by avoiding
– Unnecessary repetition of units within the table
– Data labels on every point of the chart
• Remember: Charts are best for showing general level or
shape, not precise values
– Excessive number of digits and decimal places
• See chapter 4 of Writing about Numbers or Writing about
Multivariate Analysis.
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Reducing duplicate labeling
• If every variable in the table is reported in
dollars, don’t need to put “$” in every table cell
– List the units in the title
• If an entire column is reported in percentage
units, don’t need to put “%” in every cell.
– List the units in the column label and convey “% of
what”
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
What does “well-organized” mean?
• Structure should be easy to follow based on
conventions for labeling and reading.
• Coordinated with prose description of table or
chart. Usually means
– Theoretical criteria
– Empirical criteria (ascending or descending order)
– See podcast on organizing data in tables and charts
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Writing an effective title
• Pertain specifically to content of that table or
chart.
– What question is that table/chart intended to answer?
• Include all “the W’s”
– “What” is the topic of your table? Mention:
• Outcome (dependent) variables.
• Predictor (independent) variables.
– “Who, when, where”?
• If source name is too long, put it in a footnote.
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Examples of titles
• Poor: “Descriptive statistics”
– Way too general. Omits information about the topic, context,
and types of statistics.
• Better: “Poverty patterns”
– Identifies the dependent variable (poverty), but doesn’t convey
what patterns (comparisons) are presented.
– Among who? When? Where?
– What are the units for each of the variables reported in the
table?
• Best: “Number and percentage poor by age group,
United States, 2002”
– Identifies dependent and independent variables, context ,and
units.
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Anatomy of a table
TITLE: Name the “what”, “who”, “when,” where,” and “by”
variables
Column Spanner
Major row header
Column header
Column header
Column header
Table cell
Table cell
Table cell
Table cell
Table cell
Table cell
Table cell
Table cell
Table cell
Table cell
Table cell
Table cell
Row header
Subgroup 1
Subgroup 2
Row header
Major row header
…
*Footnote (i.e., source of data, definition of terms, acronyms)
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Population, number and percentage poor,
by age group, United States, 2002
Age group (years)
Number poor Total population
(1,000s)
(1,000s)
% poor
<18
12,133
72,653
16.7
18–64
18,861
177,934
10.6
3,576
34,385
10.4
34,570
284,972
12.1
65+
Total
Note: “Poor”: family income below the federal poverty threshold for a family of given
size and age composition.
Source: Proctor and Dalaker. 2003. “Poverty in the United States: 2002.” Current
Population Reports. P60–222. Washington, DC: US Government Printing Office.
Check: W’s: Who, what, when, where?
Check: Units or categories for all variables shown?
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Anatomy of a pie chart
• Composition of a
categorical variable
• Categories are identified
in the legend
• Units in the data labels
• W’s in the title
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Anatomy of a simple bar chart
• Bivariate association between
– a categorical independent variable
on the x-axis,
– a continuous dependent variable
on the y-axis.
• Variables are identified on the
axes, along with units (y-axis) or
categories (x-axis).
• Note that categories are sorted
in descending order of the
value of the dependent
variable, facilitating a wellorganized written description.
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Anatomy of a multiple-line chart
• Three-way association
between one continuous
and one categorical IV and a
continuous DV.
• The dependent variable and
its units are on the y-axis.
• The continuous IV and its
units are on the x-axis.
• The categorical IV is labeled
in the legend.
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Range of values
of independent variables
• Choose range of values for continuous independent
variables that fit the topic and data.
• E.g., in model of birth weight:
– Mother’s age at child’s birth plotted from 15 to 45 years
of age.
• Corresponds with reproductive age range for women.
– Income/poverty ratio (IPR) plotted from 0.0 to 5.0.
• Range that captures most of the observed values in the
data set used to estimate the model.
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Writing sentences about a
a table or chart
• Use title, labels, and footnotes to identify
– The W’s
– Units of measurement
• The contents of a specific table cell are identified
by the labels on the pertinent rows and columns.
• The meaning of a specific point on a chart is
identified by the pertinent axis labels and legend.
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Population, number and percentage poor,
by age group, United States, 2002
Number poor
Age group (years)
(1,000s)
Total population
(1,000s)
<18
12,133
72,653
16.7
18–64
18,861
177,934
10.6
3,576
34,385
10.4
34,570
284,972
12.1
65+
Total
% poor
For the number in the green (underlined) cell, the row label
(yellow) identifies the age group, the column label (blue)
identifies the concept being measured and its units, and the
table title identifies the W’s.
“There were more than 12 million poor children (<18 years)
in the United States in 2002.”
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Check: Self-contained pie chart?
• Write a sentence about
the blue slice.
• “In 2004, 16% of 4 yearolds in the US were
obese.”
• Check: Identify the
– category in the legend,
– units in the data labels,
– W’s in the title.
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Check: Self-contained bar chart?
• Describe transpiration under
the bright light condition.
• “The bright light condition
resulted in the second highest
rate of transpiration (5 ml/
m2/30 minutes). Only the fan
(wind) condition yielded faster
transpiration (8 ml/m2/30
minutes).”
• Check:
– Concepts and units on the axes
and footnote
– W’s in the title
– Rank order (direction)
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Summary
• Design your tables and charts to be
– Self-contained
– Succinct
– Organized to coordinate with associated narrative
description
• Follow standard conventions for anatomy of
tables and charts
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Suggested resources
• Chapters 4, 6, and 7 in Miller, J. E. 2004. The Chicago
Guide to Writing about Numbers
OR
• Chapters 4, 5, and 6 in Miller, J. E. 2013. The Chicago
Guide to Writing about Multivariate Analysis, 2nd
Edition.
• Miller, J. E. 2007. “Organizing Data in Tables and Charts:
Different Criteria for Different Tasks.” Teaching Statistics
29 (3): 98–101.
– And related podcast
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Suggested practice exercises
• Study guide to The Chicago Guide to Writing about
Multivariate Analysis, 2nd Edition.
– Problem sets for
• Chapter 5: questions 2, 5 and 7
• Chapter 6: questions 2, 3, and 4
– Suggested course extensions for
• Chapter 5
– “Reviewing” exercise #3
– “Applying statistics” exercise #3
– “Writing and revising” exercises #3 and 4
• Chapter 6
– “Reviewing” exercises #1 and 2
– “Applying statistics” exercises #1 and 2
– “Writing and revising” exercise #3
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.
Contact information
Jane E. Miller, PhD
jmiller@ifh.rutgers.edu
Online materials available at
http://press.uchicago.edu/books/miller/multivariate/index.html
The Chicago Guide to Writing about Multivariate Analysis, 2nd edition.