PSY 652: Research Methods in Psychology I

Introduction to Data Visualization

Kimberly L. Henry: kim.henry@colostate.edu

What is a visualization?

“A visualization is a representation designed to enable exploration, discovery, or communication.” – Dr. Alberto Cairo

Why create visualizations?

Why start with data visualization?

Good Reason #1

Artwork by @allison_horst

Good Reason #2

Good Reason #3

Artwork by @allison_horst

The INCREDIBLE POWER of data visualization

Great potential for harm (part 1)

Great potential for harm (part 2)

• Narrative: This chart from the National Review presents the average annual global temperature from 1880 to 2015, showing little visual change in the line representing temperature. The y-axis ranges from 0 to 110 degrees Fahrenheit, which minimizes the visible change in temperature over time.

• Message: The intention behind this chart appears to be downplaying the significance of global warming by making it seem like the temperature has remained relatively constant, suggesting that concerns about climate change are overblown.

Great potential for harm (part 3)

• Narrative: This graph takes a similar temperature record but places it in a context that highlights the critical threshold for human civilization and sea level rise. It shows that even a small change in average global temperature (from 56.8°F to 58.2°F) can have significant impacts, such as sea level rise and other environmental consequences.

• Message: By setting the temperature within a range that shows the implications of crossing certain thresholds, this chart emphasizes that even minor increases in temperature can have severe consequences for human civilization, highlighting the urgency of addressing climate change.

• The on-chart annotations provide contextual information about the implications of certain temperature levels. Here’s what they refer to:

  1. “56.8°F”: This annotation indicates the baseline average annual global temperature in degrees Fahrenheit. It likely represents the starting point for the time period displayed, emphasizing how much the temperature has increased from this baseline.

  2. “Civilization: at line”: This annotation suggests that the average global temperature (around 56.8°F to 58.2°F) is within the range that has allowed human civilization to thrive. It implies that maintaining temperatures within this narrow range is crucial for the stability of modern civilization.

  3. “200 feet of sea level rise”: This annotation highlights a critical threshold where significant global temperature increases could lead to drastic sea level rise. It emphasizes that even a few degrees of warming can result in catastrophic environmental changes, such as the melting of polar ice caps and subsequent sea level rise, which could inundate coastal cities and affect millions of people.

  4. “Last Ice Age”: This annotation indicates a much lower temperature range (below 50°F) that was characteristic of the last Ice Age. By placing this annotation on the chart, it contrasts the current and slightly warmer temperatures with much colder conditions in Earth’s past, underscoring how relatively small changes in average global temperature can have large-scale effects on the planet’s climate.

Great potential for harm (part 4)

Two charts from the WAPO article mentioned previously.

But also, a great potential for positive impact

Variations of Earth’s surface temperature:

Michael Mann, Ph.D., a Climate Scientist, created this graph in 1999. It is believed by many to be one of the most influential charts ever produced.

• Narrative: This graph (commonly referred to as the hockey-stick chart) presents a long-term view of temperature changes over the past 1,000 years, showing a relatively stable climate until a sharp rise in temperatures in the 20th century. It illustrates the unprecedented and rapid increase in global temperatures in recent history.

• Message: This graph tells a powerful story of how recent human activity has dramatically altered the Earth’s climate, with the steep rise in temperature being a clear signal of anthropogenic global warming. It counters the narrative of the first graph by showing the historical context and the significance of recent changes.

Alberto Cairo’s 5 key principles of an effective visualization

The “hockey-stick” chart embodies Alberto Cairo’s 5 key principles of an effective visualization

1. It is truthful, as it’s based on thorough and honest research.
2. It is functional, as it constitutes an accurate depiction of the data, and it’s built in a way that lets people do meaningful operations based on it (seeing change in time).
3. It is beautiful, in the sense of being attractive, intriguing, and even aesthetically pleasing for its intended audience—scientists, in the first place, but the general public, too.
4. It is insightful, as it reveals evidence that we would have a hard time seeing otherwise.
5. It is enlightening because if we grasp and accept the evidence it depicts, it will change our minds for the better.

Truthful

Functional

Beautiful

Insightful

Enlightening

Do these charts meet the criteria?

For each of these charts on the following slides, please evaluate the extent to which they adhere to Cairo’s 5 principles.

Gun ownership

Heights

40 is the new 20

Electoral college (contrast the two)

Dots are proportional to the winner’s vote total in each county.

Flatten the curve

CO2 during COVID-19

Wildfires

Emissions

How much hotter?

This is an interactive graphic. To access the material, press and hold control, click the link below, and choose “Open Link in New Tab”.

Click here to experience the graphic.

Enter your ratings

After you’ve discussed the charts with your partner, enter your personal ratings for each chart below. To access the survey, press and hold control, click the link below, and choose “Open Link in New Tab”.

Click here to take the survey.

A step by step guide to a great chart by Cole Nussbaumer Knaflic

The steps

• Understand the context
• Choose an appropriate display
• Eliminate clutter
• Draw attention where you want the audience to focus
• Think like a designer
• Tell a story

An example

Decades of rising income inequality and slowing economic growth have significantly eroded a core element of the American dream: the belief that each generation will fare better than the one before.

Our goal: To visually illustrate the dramatic decline in economic mobility in the United States over time. That is, to highlight how, over the past several decades, the likelihood of children earning more than their parents has sharply decreased, signaling a significant shift in the economic landscape.

Step 1: Understand the context

Begin by identifying your audience and their needs. What is the key message you want to convey? Consider what data you have available and how it can support the story you aim to tell.

The audience and key message

• Audience: Students, educators, policymakers, and possibly a general public interested in economic and social issues. They may have varying levels of familiarity with the underlying data and research methods but share a common interest in understanding the factors contributing to economic mobility and inequality.

• Audience Needs: The audience needs a clear, compelling visualization that highlights the decline in economic mobility and its implications. They are looking for a visual that not only presents data but also helps them grasp the broader narrative of how the American dream is changing and what that means for future generations.

• Key Message: The key message to convey is that economic mobility in the U.S. has significantly declined over the past few decades, primarily due to rising income inequality (a smaller proportion of people own the majority of income/wealth). This decline has profound implications for the American dream, as fewer people are able to surpass the economic success of their parents.

Data available

The available data includes trends in absolute economic mobility across different birth years (cohort), highlighting the proportion of 30-year-olds (age30_absmob) and 40-year-olds (age40_absmob) who earned more than their parents at the same age. The data were collected by Dr. Raj Chetty and colleagues of Opportunity Insights.

Step 2: Choose a display

Select the type of chart or graph that best represents your data. Whether it’s a bar chart, line graph, scatter plot, or something else, the choice should make the data easy to interpret and relevant to the audience.

A bar chart 🙁

A line graph 🥰

Step 3: Eliminate clutter

Simplify your visual by removing any elements that do not add value. This includes unnecessary gridlines, labels, or colors that might distract the viewer from the main message.

Remove the legend, annotate instead

Step 4: Draw attention where you want the audience to focus

Use design techniques like contrast, color, or annotations to highlight the most important parts of your chart. This ensures that the audience’s attention is drawn to the key insights.

Bold lines and text, use a minimal background

Step 5: Think like a designer

Pay attention to the overall layout, alignment, and spacing in your chart. Ensure that it is visually appealing and easy to read. Consistency in design choices can make your chart more professional and understandable.

Left align the title and try a different font

Step 6: Tell a story

Finally, craft your chart to convey a narrative. The data should guide the audience through a beginning, middle, and end, ultimately leading to a clear and compelling conclusion.

Addition of narrative elements