VizWiz

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Showing posts with label bubble chart. Show all posts

May 30, 2023

How to Create a Radial Bubble Chart in Tableau

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If you’re looking for something beyond the basic line chart in Tableau, this radial bubble chart might be exactly what you’re looking for. And the best part, it only takes 6 calculations and 8 steps. 

But be careful, this isn’t the easiest chart to read. Use it with caution and make sure you understand your audience.

A special thank you to Trea McElhone at The Data School for teaching me how to create this. I extended her work to do all of the calculations directly inside Tableau, which helps it be flexible for more use cases as I demonstrate.

DOWNLOAD the data and starter and solution workbooks for $2 (this covers the costs of making this and future videos):

I would appreciate your support, however, if you want the Excel files for free, download them here:

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First, we’ll create all of the calculations.
Second, we’ll build and configure the chart.
Lastly, we’ll use parameters to customize the chart to make for a great user experience.

February 13, 2017

Makeover Monday: How Much Do Americans Spend on Valentine’s Day?

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Because I'm tend to forget Valentine's Day (I consider it a Hallmark Holiday), it almost passed me that this week included Valentine's Day and I had intended to use another data set for Makeover Monday. Fortunately we have people on Twitter to keep us straight and this tweet changed the theme for this week.

This meant spending my Sunday morning find a new viz and data set. A quick google search turned up this infographic from KarBel Multimedia:


What I like:
  • Color choices that match the theme
  • Simple title that tells me what I'm about to see
  • Proper sourcing
  • Nice description that include a question that explains what the viz is about
  • Donut chart works well here as it's only 2 slices
  • Clear labeling

What could be improved:
  • Why use bubbles to compare the sizes of the spending? A bar chart would be way easier to read.
  • There's very little context. Is this spending increasing or decreasing?
  • While the color choices work for the theme, this sure is A LOT of pink.

For my viz, I wanted to create a mobile version that looks at the historical spending trends in two groups: significant others and everyone else. I don't lover my effort this week (pardon the pun), but there's only so much time in a day. Lastly, special thanks to Eva for the color palette.


September 19, 2016

Makeover Monday: Data breaches are getting bigger and more frequent

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Several people have recommended Makeover Monday for the Project of the Year in the Kantar Information is Beautiful Awards, which I must admit is quite stunning and flattering at the same time. The suggestion for this week’s makeover came from Andy Cotgreave. We intentionally picked something from Information is Beautiful with the hope that it gets a bit more exposure. Shameless perhaps, but what can it hurt? This viz from David McCandless certainly deserves a makeover.


What works well?
  • The viz is eye-catching and definitely draws you in. There’s something to say for that.
  • The interactivity is fantastic.
  • Good filtering, colouring and sizing options

What doesn’t work well?
  • The bubbles move all around for no apparent reason.
  • There’s way too much overlapping, making it hard to identify any insights.
  • Whether something is interesting is extremely subjective. I wouldn’t make these same choices.
  • The viz doesn’t fit in a single view, requiring too much scrolling.
  • Not all records are included. I guess this was done for artistic purposes as David is known to do, but it distorts the message.

I decided to work on my makeover during my flight to Prague, thus imposing a time limit on me. I started by creating a view that simply shows the number of data breaches by year using circles. This basically flattens out the original.


While this shows the distribution nicely, I don’t love it. Next, I converted the circles to squares, hoping the result would be more visually impactful as the squares take up more space.


This is definitely better, however I don’t like how it doesn’t incorporate the records stolen in each data breach well enough for my liking. So I decided to add a dot for every breach in the data set and change the location of each dot to the number of records stolen.


Getting there…iterating is really helpful. This shows some of the outliers really well, but I feel like I’ve lost the distribution a bit. I decided to quickly open the data in Vizable and when I switch the view to records stolen by year, Vizable presented me this interesting view that shows the median and the distribution.


I really liked this so I decided to build upon it in Tableau. My final viz incorporates the view from Vizable, the distribution of each data breach and allows me to focus the story on data breaches that were hacks versus not hacks.

Click to view interactive version

I find this final view much, much easier to look at than the original and also it provides much better context. For me, context is key. Every visualisation you create should include context somehow. Why? Context makes it much easier for your audience to understand the story.

March 3, 2016

Dear Data Two | Week 44: Distractions


For week 44, I tracked all of the things that distracted me. The data I collected included:

  1. When did I get distracted?
  2. What was I doing at the time?
  3. What distracted me?
  4. How long was I distracted?


When doing the analysis in Tableau, I started doing what I always do by building lots of different views. I started with how many, but there weren’t any days that were massive outliers. When looking at how long I was distracted, there was a big outlier on Wednesday. That was because we had Caroline Beavon teaching in amazing data visualisation class at the Data School and she introduced us to an infographics design tool called Piktochart. This is when I distracted myself. It was fun to play with and got me thinking more about design.

I built several more views looking at the different dimensions against the different measures. Nothing particularly exciting…until I built a bubble chart in which I colored the bubbles by whether or not social media was the distraction.


I generally have a disdain for bubble charts, but this particular view helped me easily see how often social media is a distraction. Does this mean I’m on my phone too much? Probably!

The view above simply looks at how often, meanwhile looking at the bubble chart by how long the distractions lasted makes social media distractions look not so awful.


Lastly, I needed to find a view that would allow me to incorporate all of the dimensions along with the length of each distraction into a single view. I came up with this viz:


Here are some of the design decisions I made:

  • Show the day of the week left to right
  • Inside each day, show the distractions in order from first to last going left to right
  • To show what I was doing and what distracted me, I wanted to go with the idea of going from something to something else. I ended up with filled circles inside open circles. The open circle is what I was doing; the filled circle is what distracted me.
  • Create groups of activities and distractions so that there aren’t too many colors


Lastly, I liked what Stefani did for her week 44 with the lines, so I tried to do something similar with my postcard version while maintaining the view I created in Tableau.

May 18, 2015

Makeover Monday: How Much Water Is Used to Produce Your Food?

Quick makeover this week (we have a Segway tour of Boston at #Inspire15 in 30 minutes). I saw this graphic on the LA Times about the amount of water it takes to produce a single ounce of food.

It’s cute and it’s interactive, but it’s not very good for making comparisons or ranking. Bubble plots are notoriously difficult this way. For example, tell me quickly which food uses the 3rd most water? Tough to tell, right? I also don’t understand why they grouped fruits and vegetables together.

I manually recreated the data in Excel, which you can download here. Hopefully I recorded everything correctly; if not, please let me know. I then quickly built a chart in Tableau. I’ve addressed the issues that bubbles present, ranking and comparison, by using a bar chart instead.

Going back to the previous question, using my viz, which food uses the 3rd most water? Simple right? How about the 10th most vegetable? That’s simple too; all you need to do is click the color on the right.

April 13, 2015

Makeover Monday: David Cameron's Overseas Trips

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It's election season in the UK and The Guardian recently released some data related to Prime Minister David Cameron's travels around the World. They provided a table of all of the data at the bottom of their post, but the only viz they provided was this view aggregated by continent.


First, bubbles make comparisons harder than they need to; bar charts are much better for comparisons. This view also doesn't provide any addition insight. I can't answer a simple question like "Which countries did Cameron visit in Europe and when?"

I only had a few minutes this morning to create an alternative and here's what I came up with in about 15 minutes.


September 1, 2014

Makeover Monday: Where We Donate vs. Diseases that Kill Us

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One of the ways that I can tell I've made an impact on people I've interacted with is when they send me links to terrible visualizations that they want me to makeover, long after we have worked together. My friend Karyn, who I used to work with at Facebook, send me a link last week to this infographic:

Source: IFLScience

Of course the point of this infographic is to show how much money the ALS Ice Bucket Challenge has raised compared to how few die from the disease relative to other diseases. The data is from 2011, so it doesn't account for the fact that the Ice Bucket Challenge has now raised over $100M. For the purpose of this makeover, let's focus on the chart itself. I see several issues immediately:
  1. The bubble sizes were originally based on the diameter of the circles, not the area.  This is a big mistake! The author has since fixed this so the graphic above is now correct.
  2. There are too many colors. I find myself going back and forth to the legend. It shouldn't be so hard for the readers.
  3. The colors in the legend are in no particular order; not alphabetical, not by deaths, nor not by money raised. This is way too confusing.
  4. It's difficult to trace the relationship between the deaths and the money raised. 
Taking these difficulties into account, I have created this slope graph.


Some of the benefits of presenting the data with a slope graph include:
  • We can see the ranking relationship between the cause and the disease much easier. 
  • I've highlighted the Ice Bucket Challenge since it is the focus on the article.
  • I colored the remaining line by red or blue to indicate a decline or increase in rank respectively.
  • I labeled the ends of the lines directly to eliminate the need for a legend.
One additional element that would add value to the slope graph would be to include the bubble size. If you'd like to build your own infographic, you can download the data here and/or the Tableau workbook here.

February 8, 2013

Taking the Kraken to U.S. federal government spending

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I was watching a video from Simon Rogers the other day about data journalism and how he got started.  During his TEDx talk he showed this bubble chart that he created on government spending in the UK.

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This reminded me that Tableau 8, the Kraken, now has the ability to create bubble charts.  They’re not quite as sophisticated as what Simon created, they’re more like what you can build with ManyEyes, yet, like most of Tableau’s features, they’re unbelievably simple to build.

I downloaded data about US federal government spending in the 2013 budget from Wikipedia, connected to it with Tableau and within 3 clicks I had my bubble chart.

Clicks 1 & 2 – Select Agency and Total (which is total spending)

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Click 3 – Click the packed bubbles option from Show Me

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And here’s what you get:

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This is pretty boring, so I placed Total on the color shelf and changed the color palette to red-blue diverging and reversed them.

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That’s about six clicks and I have something pretty interesting.  But that’s not enough for me.  I wanted some interactivity.  A few minutes later and this is what I created:

Is it perfect?  No.  Give it a whirl.

  • Play around with the selectors.  Notice how the sheet colors change from a measure to a dimension.  Download the workbook and see if you can figure out how I did it. 
  • Click on a department in the table to highlight it’s bubble. 
  • Notice how the table sorts based on the spending type you pick.  This makes finding the top few bubbles much easier.

These new bubble charts are going to be pretty useful, though I can totally see them get wildly misused.

October 24, 2012

A panther on the prowl. Finding Nelson Demille.

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On Tuesday, October 16th, one of my favorite novelists, Nelson Demille, published The Panther.  I’ve read many of Demille’s books, including two of my favorites, Up Country and Wild Fire.  I read Up Country after I was in Vietnam back in 2004 and Wild Fire just a few weeks ago.  Wild Fire was particularly interesting given the current political climate in the United States and the state of hostility by some towards the Middle East.

Demille is currently on a book tour and he’s sticking to the NE part of the US, unfortunately.  I created this viz on the train home last night so that you could go see him in person, buy his book (by clicking on the book cover), and send me a signed copy.

Thanks in advance!

Question: The bubbles are a simple calculated field that compares the date of the event to the current date (if today() > [Date] THEN 'Yes' else 'No' end), however when published, Tableau does not evaluate the expression and the bubble colors are not updating automatically.  Has anyone seen this?

March 16, 2012

Fixing Nielsen’s bubbles (and tips for effectively organizing and displaying data)

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The chart below comes from a recently released study by Nielsen.  With some simple fixes, this data can communicate much more effectively.

I find this chart hard to read and interpret because:

  1. The data is not aligned vertically, making comparisons across categories for the same country difficult.  For example, your eyes are constantly pinging left to right to left trying to compare the UK values.  It kind of makes me feel like I’m in a tennis match.
  2. The bubbles are not sized according to their percentage, making comparing bubble sizes meaningless and inaccurate.  You can’t tell me that the orange Italy bubble for Downloaded Music is 1/3 the size of the US bubble.
  3. There doesn’t seem to be any logic to the order of the categories.  At first I thought they were sized by the US percentages, but that’s not it.  Maybe they’re ordered by the total?  Nope.  I have no idea!

There are two better alternatives for presenting this data.  First, if you like the bubbles, then a viz like this works. 

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With this viz, it’s so much easier to compare values both across and down.  It’s easier to compare bubble sizes, you don’t have to lookup the colors since they’re organized in columns, and the bubble sizes are relative to each other.  Look at Downloaded Music in Italy now: 20% now looks like it’s a bit less than 1/3 the size of the US bubble (62%).

Note that I would normally have ordered the categories alphabetically, but I sorted them in the same order as the Nielsen viz so that you could compare the mine and their’s more easily.

A second alternative would be a simple bar chart like this.

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This chart also addresses the comparison problems.  The gridlines make it especially easy to compare categories within the same country, though your eyes do have to skip over three other bars before getting to the next one.

Bar lengths are much, much easier to compare than bubble sizes, but the bar chart feels a bit more cluttered to me than the bubble chart.  In this situation, I would use the bubble chart I created. 

This goes to show that there’s more than one way to skin a cat.

November 18, 2011

The Best NFL Kick Returners Ever!

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Using Tableau is a never-ending journey of learning and today was no exception.  It began with this chart from the Chart of the Day:

Overall, this chart is well executed, except I would have sorted the players in descending order.  But I wanted to take it one step farther, so I downloaded the data from pro-football-reference.com and got to work in Tableau.  I wanted to be able to compare:

  • Not only the combined kick returns, but also the top punt returners and kickoff returners separately.  I wanted to know which players were the best in each category. 
  • Players that played for one team versus more than one team
  • A player’s kick return ability compare to his punt return ability

Finally, I wanted to be able to filter each chart by the Top X Players for that chart.  This is where parameters come in handy.

I started this post by saying I learned a few things.  I learned to:

  • Make the user experience easier by creating a list of instructions like Steve Wexler at DataRevelations.com always does. Hover over the NFL logo to see the instructions for this viz.
  • Filter by a Top X parameter when there’s more than one item on the color shelf (like on the Total TDs chart).  Check out this discussion on the Tableau forum for an explanation (thanks to Joe Mako for the link and help making it work with a scatter plot).

To answer the question in the title of the viz, Devon Hester is very dangerous…a clear outlier, he’s a player that is “numerically distant” from the rest of the players.

October 14, 2011

Global Consumers Go Bubble Popping

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Nielsen is at it again.  Just when I thought they were making strides in the right direction, they bring me back to reality.  As with most Nielsen articles, this one is well written with lots of facts that are explained in an easy to understand manner (kudos to them for writing well).  There’s even a nice bar chart that ranks survey responses.  But then, they throw this junk in there:

Is it just me, or is this screaming out for another bar chart?  Maybe they’re afraid they’ll bore their audience with another bar chart, so they throw in an unnecessary ranked bubble chart to gain your attention.  Are they THAT desperate?  Why not represent it like the bar chart below?

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Or better yet, show the data itself.  It tells the same story, but only simpler and you don’t have to try to infer any additional meaning from the size of the bubbles.

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My faith and resolve are not shaken though.   Eventually they’ll get annoyed by my emails and write me back.