Same Data, Different Stories

In today’s world of fake news I thought I might write a post about how easy it is to tell different versions of the truth simply by manipulating the same data and/or visualizing it differently. Each of my examples will be truthful, but can tell profoundly different stories.

Let’s start with the data.

Data table of US Median Earnings

For my example I chose to use the estimated US Median Earnings in dollars from the US Census website. I also chose to color code the data using blue for boys and pink for girls since these are the traditional colors associated with gender in the US.

There are a few things of note about the data:

  • First, the earnings values are the median earnings per year. It’s important to understand that median is not necessarily equal to average. Median is literally the middle, meaning that half of the population will earn more than the median and half the population will earn less.
  • Second, the % Diff is the percentage of difference between the Male and Female median salaries for the year. For example, males earned 23.3% more than females in 2005.

Let’s take a look at visualizing the data.

Looking at this chart, we would immediately think the difference between gender salaries has decreased dramatically in the last 11 years. And despite the title, it’s not clear which is the higher salary and which is the lower salary. We’re assuming our audience will know.

Now, look again at the same chart with a simple change.

As you can see, when we adjust the scale (vertical axis) to the full 100%, there’s been very little change. One of my favorite quotes is from Leon Trotsky, “Everything is relative in this world, where change alone endures.” Although I usually shorten it to just “everything is relative.” In this example, because most person’s understanding of percentages are relative to a scale of 0 – 100, the first chart’s scale can be misleading. Persons absorb charts visually so the position and movement of the line on the chart is what they are going to pay attention to first and it’s going to be relative to their perception of a percentage scale. Having a truncated vertical axis is not necessarily a bad thing as it allows us to see more detail, but it’s important to make sure that it doesn’t promote misconceptions of the data. This a more truthful chart but it still has the problem of clearly identifying which gender’s salary is higher and which is lower.

Let’s look at a chart which visualizes the median salaries.

This chart’s primary story is the growth of earnings for males and females from 2005 – 2016. Although it does show the male earnings as higher it’s not going to be the primary focus of the viewer despite the chart title. There’s a reason for that. Because it’s a line chart, there’s a perception of movement (hence line charts being so effective for a time series). So our primary perception is the increase of earnings across time and the gap between the two genders is secondary.

By highlighting the gap between the two lines (and adding data labels) the story now becomes more about the % of differences between male and female earnings as stated in the title. The visualization is perceived as one item but the focus is on the gap instead of the lines.

This chart’s story is two simple truths:

  • the gap between male and female earnings has decreased 3.6% in the last 11 years and
  • earnings have increased at a steady rate for both genders since 2005.

By manipulating the data we can create completely different stories.

This chart gives the impression of a widening gap between the earnings of male and female even though the data labels clearly show the percentage as less. That’s because the data is cumulative. Each year’s earnings is added to all the previous year’s earnings (known as a running total) to end with the total earnings for all 11 years. This is a potentially misleading chart since viewers may not take time to absorb the details required to understand it.

In this chart it appears that female’s earnings are better than male’s. That’s because it’s charting the percentage of growth in earnings and is using a truncated vertical axis. So while it’s true that female’s earnings have increased slightly more than male’s, the difference in the growth is nowhere near bringing parity to the earnings between the genders. This is also a potentially misleading chart.

Like I said at the beginning of this article, every one of these charts are “truthful” but, as you can see, there can be lots of versions of the truth. How you decide to correlate, transform, aggregate, and visualize data has a great impact on how someone perceives the story. And while it might be tempting to have your data shown in such a way that it supports your beliefs, isn’t it better (and more ethical) to show the data in as clear and unbiased way as possible?

So how can you tell your data’s story?

  1. First, consider what your data is about. My example was pretty straightforward, the difference between male and female’s median salary for the last 11 years.
  2. Next, decide how you manipulate the data in relation to your intended audience. In my examples, while calculating the percentage of difference between the genders was useful, transforming the data to running totals and percentage of growth was potentially misleading. I’m a huge fan of the KISS principle. It means Keep It Simple, Stupid.
  3. Finally, consider your visualizations carefully. Start with your main title, then imagine your visual without any other text. Your audience is going to expect the “picture” of the chart to tell the story of your title. Strive for simple truths.

I hope you found this article helpful for creating your own data stories. The samples, plus more, are available for download in an excel spreadsheet on my Visualology onedrive.

The Gestalt of Slides


I recently had the wonderful experience of sharing the Gestalt Principles of Visual Perception with my 4 year old grandson.  This might seem a pretty heady topic for a 4 year old, but we were discussing how shapes can be combined to create a picture of a house.  This is the very heart of the Gestalt Principles of Perception.

The knowledge of these principles can be a very valuable tool for designing not only slides but any form of visual communications, including photographs.

I’ve been working on a post about this topic for a while but, with the inspiration of my experience with my grandson, I decided to make a fully interactive tutorial.  Click the icon in the lower right of the tutorial below to run it in full screen mode.

I hope you enjoy learning from the tutorial as much as I had creating it and, once completed, I wish you the best as you go forward and practice the art of Pragnanz.

Why Should Presenters Care About the Psychology of the Senses?

MouseoverMagicShowThe simple answer is that presentations are intrinsically a sensory experience, primarily seeing and hearing.  And a clever presenter can also incorporate the other senses as well.

But do you really need to understand how the brain processes the information the eye sees or the ear hears?  After all, you don’t need to understand how a computer processes the information from a keyboard to use it effectively.  While this may be true, you do have to have some understanding of how the keyboard works otherwise you’d end of with a mess of letters that made no sense.

The same is true of understanding how our senses work.  You don’t really need to know that the neural circuitry of the retina transforms a fluctuating pattern of light into a pattern of neural activity in retinal ganglion cells, which is then transmitted along the optic nerve to the brain [1].  But it’s extremely helpful to know that we don’t “see” images that move very fast or very slow. 

If you read the report from my previous post, Seeing, Hearing and Smelling the World,  you would know that we are attracted to nothing as much as change.  And that applies to all the senses.  We organize our world into patterns in order to easily filter out unnecessary information and quickly recognize when something changes.  In our primal minds, change represents both danger and opportunity.  These were the tools necessary in an eat or be eaten environment.  Even today these are still the tools that allow us to avoid car crashes or identify food that’s safe to eat.  Whether we want to admit it or not, from a sensory perspective, we all have attention deficit disorder (ADD.)  Anything that doesn’t change every 5 seconds is largely ignored.

I recently attended The Presentation Summit and overheard some patrons who had attended a session on presenting webinars.  They were complaining that the session presenter had said they needed to make a change every XX seconds.   They interpreted this as needing multiple slides for every minute of the presentation/webinar.  I think they missed the point.  Webinars are the ultimate ADD environment.  Your attendees will be checking their email, typing documents or working on a plethora of other activities while you are presenting and you’ll never know it.  You are competing for their attention.  If you do not provide rapid stimulation (change) in your presentation, you will lose your audience pretty quickly.  This doesn’t mean a different slide, the change can be as simple as raising the volume of your voice or a simple highlight on a slide.  You just need some small change that tells their senses “Pay Attention!  Something has changed.”   But beware of repetition which by definition is a sort of unchange.  While a repeating animation might hold our attention for longer than 5 seconds, we’ll quickly learn to ignore it.

By knowing and understanding these concepts you can take advantage of opportunities that most magicians have known about for centuries.  There is truth in the old adage, “the hand is quicker than the eye.”  It isn’t actually, but our brains don’t process everything the eye sees.

Most people have difficulty registering identifying details about an object that moves faster than 36 degrees per second. Since your visual field is around 180 degrees, anything that crosses in and out of your visual field in less than five seconds starts to blur. And because the cells in your eyes get tired of stimulation after more than two or three seconds, anything that doesn’t move significantly in that amount of time will be perceived as stationary. [2]

This is what allows us to make films.  They are simply a series of still images strung together and presented rapidly enough that our brains perceive motion.  You can use this knowledge to add interest as well as dynamic and subtle changes to your presentations.

In my quirky presentation called the Mouseover Magic Show, I used these concepts to do something that the software (Microsoft PowerPoint) is very limited in supporting.  If you download the presentation and run it, you can move your pointer over any mouse and they will appear to change.  In actuality, it’s jumping to a whole new slide, but because the background doesn’t change, we only recognize the change of the mouse.  We aren’t aware the entire slide has changed.  I’ve created this simple slideshow specifically to illustrate this technique for creating mouseovers.

If I’m the PowerPoint Magician, my friend Julie Terberg is the PowerPoint Illusionist.  She applies the concepts of visual motion in an elegant and sometimes surprising way that’s sure to hold an audience’s interest.

PowerPoint 2010 has some new transitions that are specifically designed to exploit this quirk in our visual sense.  They’re called Dynamic Content Transitions.  They provide movement of the content on the slide without moving the background.  You can achieve pretty spectacular effects using just the transitions.  I discussed these transitions on the Indezine Blog and posted a downloadable timeline template that uses these transitions. You must run the template in the desktop version of PowerPoint to see the transitions properly.

Every presentation should have an element of magic to it.  Every presentation should have its prestige (a mysterious quality of enchantment) moment.  Nancy Duarte calls this the STAR moment in her new book, Resonate.  It’s the moment where you’ve connected with the audience on such a primal, emotional or spiritual level that they feel compelled to pay your message forward again and again.  Understanding the psychology of the senses will help you create this moment.

Finally, if you downloaded and ran the Mouseover Magic Show you might have noticed the card trick.  The how and why that works is a discussion for another day.

[1]  Visual Perception: physiology, psychology, & ecology By Vicki Bruce, Patrick R. Green, Mark A. Georgeson

[2] How Fast Can the Eye See? |

Seeing, Hearing and Smelling the World

Seeing, Hearing and Smelling the WorldI originally thought my first substantive post would be about the Gestalt Principles of Perception.  However, I realized it would be best to begin by laying a foundation upon which an understanding of the psychology of the senses could be built.

One of my favorite resources is the (now updated) 1997 report from the Howard Hughes Medical Institute on Seeing, Hearing and Smelling the World.  It provides a nice background on how our brains process information using sight, sound and smell.

Download a pdf of the report.

Welcome to Visualology

Let me start by saying I’ve wanted to write a blog for a while because I love knowledge and I love sharing knowledge.  My problem has been what to blog about.  I knew I wanted it to be about presentations and PowerPoint (which I love.)  My problem was deciding which particular area of my expertise could I write about that would hold the interest of an audience and be the most useful.  Would it be assistive technology, collaboration, interactivity, educational games, information design, digital dashboards, project management, etc.?  My skills in this area are eclectic and usually very technical.  I was looking for that one special topic that could be uniquely mine.  So what was it to be?

I was reading Stephen Few’s books on data visualizations when I finally had my blog epiphany.  One small section covered the topic of the Gestalt Principles of Perception.  I immediately experienced an instance of déjà vu and felt like I’d hitched a ride on Mr. Peabody’s WABAC (way back) machine.

You see once upon a time in a land far away, I was a mental health therapist in the Navy.  In fact, if things had turned out differently I might have been a psychiatrist.  I loved doing therapy and it was especially gratifying to change someone’s life for the better.  And even better than that I met my husband who was also a therapist and I couldn’t have asked for a better soul mate.

But life has a way of throwing you curve balls and sometimes the best you can do is a base hit.

At the time I got out of the Navy work as a therapist was best described as thin and I would’ve had to go to school for 12 years to be able to do the same therapy I’d been doing for the previous 5 years.

So my husband and I made a deal; he’d continue to be a therapist (ultimately earning his Masters in Psychology) and I’d take a different path.  After falling in love with the Commodore 64 and naturally being attracted to the latest, coolest thing it didn’t take much to lure me to the dark side of computer geekdom where I’ve happily lived since.

So here I am, come full circle.  This blog is going to be about psychology.  Specifically, it’s about the psychology of visual perception and how that knowledge can be used to design better presentations and visual communications.  I intend to refresh what I already know and learn what I don’t know and share it here.

Even more, this blog will be my tribute to my husband of 30 years who passed away in 2009.  He would’ve loved this topic and he would’ve loved talking about it, challenging the concepts and expanding our minds and understanding.