CoolData blog

9 December 2009

Cool motion charts – Part 3

Filed under: Data visualization, Free stuff — Tags: , , , — kevinmacdonell @ 11:21 am

In Part 1 I introduced the concept of using Google Gadgets to visualize our data. In Part 2 I gave an example of an alumni giving history visualization.

Today I will offer some additional notes on how the Giving chart spreadsheet was assembled. As I said before, assembling the data was a lot more work than actually making the chart! It would be helpful for you to have query access to your institution’s database for this, but if you can get your IT people to extract the data, you should be able to prepare that data in Excel.

I started with an MS Access query of our database (Banner) which gave me a row for every single alumnus/na, living and deceased (about 43,000 records), donors and non-donors, with a column for Class Year, and a column for Total Giving for each fiscal year from 1989 to 2009.

(Each fiscal year total was in fact a sub-query – there’s definitely some work involved. Luckily I had all these sub-queries already made, from previous data projects. Gathering all this data by individual may not be the easiest way to go about this. If you can obtain data that is already aggregated in some way, such as by class year of donor, go for it.)

The length of your time series will be limited by the depth of historical giving data available in your database – ours happens to go back 20 years.

Let’s look at the final spreadsheet we need to create. Here are the first few rows of mine:

We need to collapse our tens of thousands of rows of data on individual alumni into something like what you see above. This is a lot easier to do with a statistics software package, but no doubt it can be accomplished in Excel as well.

I use Data Desk for stats. Paste all your individual giving data into a new data file. The first step is to create a derived variable to recode Class Year into decades (1930s, 1940s, etc.) These will be used to populate the first column of our spreadsheet.

The first column defines the ‘bubbles’. The last column (Category) gives the bubbles names. The two columns contain exactly the same data, but the gadget requires this label information to be contained separately.

The second essential column is the time-series data, in this case Year. This isn’t Class Year – this is the fiscal year in which gifts were made. Year is the variable reflected in the time slide-control at the bottom of the chart.

Creating the spreadsheet was a bit tedious from this point on. It involved a lot of cutting and pasting of the desired values from Data Desk into an Excel spreadsheet. You may be able to vastly improve on my methods.

The middle column, Number Alumni, is the count of individuals in each Class Decade. The relative size of each bubble is based on this number, from 719 in the 1930s to more than 10,000 in the 2000s. (I’ll show you how to define bubble size later.)

The other columns provide the data that will form the x-axis and y-axis of the chart.

In my chart, % Participation or Number donors can be on the x-axis – you can choose one or the other. (% Participation = Number donors divided by Number alumni.)

And finally, the data in the column Median $ is used for the y-axis.

As I said, I used Data Desk to help do the calculations and order the data properly before pasting it into Excel and getting it all arranged properly. Here is a Data Desk Summary by Groups table showing giving totals by Class Decade for the year 1995:

This provided me my donor counts as well as my median giving data. Of course I had to do the same thing over and over for each fiscal year, 1989 to 2009.

Give it a shot. Use the tools you’ve got to massage your data until it’s in the form of the spreadsheet I showed above. This really is the time-consuming phase of your project. Once you’re done, the rest is surprisingly easy. I’ll get to that in Part 4.

8 December 2009

Cool motion charts – Part 2

Filed under: Data visualization, Free stuff — Tags: , , , , — kevinmacdonell @ 7:43 pm

In my previous post, Cool motion charts – Part 1, I talked about a Google Gadget which allows you to make a motion chart based on a spreadsheet of data you create in Google Docs. Now I will show you a live example I created. In Part 3, I will go into more detail about how you can create your own.

WordPress does not allow embedding of scripts, and Google Gadgets are scripts, so you’ll have to click on the link below to view the motion chart. The spreadsheet will open in a separate tab or window. Click on the “Motion Chart” tab at the lower left, then wait a moment for the chart to build.

(See note at bottom of this post for some caveats related to this data.)

Motion chart, "20 years of alumni giving". (Click to access.)

When you click the Play button in the lower left-hand corner, the animation runs from fiscal years 1989 through 2009. At any time you may click and drag on the time scale to control the year being displayed. Animation speed control is to the right of the Play button.

Each circle represents a class decade (1930s to 2000s). The size of the circle corresponds to the number of alumni, living and deceased. Click on any circle to highlight that decade. (Click on ‘Trails’ to record how it moved over time.)

The vertical axis is Median Gift for that fiscal year. I used median instead of mean (average) to avoid huge swings due to the influence of large outlier gifts.

The horizontal axis is Percentage Participation for that fiscal year. I just noticed that the gadget has converted all my percentages to decimals, as in 20% = 0.20. (If you click on % Participation, you have the option of changing the view to Number of Donors. Those are the only two views that make any sense.)

It took a lot longer to prepare the data for the spreadsheet than it did to produce the chart. Click on: Part 3 (data preparation) to continue!

[Note on data: Actual donor participation figures we have published are higher than this chart suggests, as multi-alumni households (which are common for our institution) are counted here as a single donor when gifts are not split. As well, giving figures include both annual and campaign gifts, but exclude student giving (via union fees), estate giving, and all other non-alumni giving.]

Cool motion charts – Part 1

Filed under: Data visualization, Free stuff — Tags: , , , , — kevinmacdonell @ 8:13 am

I’ve started using some cool things for visualizing data which don’t involve buying and learning new software.

Google Docs has some new features called “gadgets” which allow you to do some interesting things. One of these is a Maps gadget which works with your Docs spreadsheet to whip up maps with pushpins of the addresses you post in your spreadsheet. I’ve been using it to plot addresses for our Planned Giving Officer for trip planning. It could function as an alternative to MapPoint. Bonus: it works great with Canadian addresses, as long as they’re true street addresses.

I’ll post on that another day, because way higher on the fun-o-meter is the Motion Chart gadget, which again works with a Google Docs spreadsheet to create an animated chart of time-series data.

I recently created a motion chart for alumni giving to our university for the past twenty years. It’s a bit hard to describe, but basically when you hit ‘play’ the animation begins running from 1989 to the present, and coloured bubbles representing each class decade from the 1930s to the 2000s start wandering around like planets, according to two values: median giving for the fiscal year (on the vertical axis) and percentage donors for the fiscal year (on the horizontal axis).

Screen shot of motion chart for "20 years of alumni giving", stopped at 1995. (Click for larger version.)

I’ve played it back many times – it’s an interesting way to view a ton of data all at once. In fact, because the underlying spreadsheet has 6 columns and 168 rows of data, the animation allows you to visually absorb the information contained in 1,008 cells! Behavioural differences among class decades become visible, as well as the general effects of campaigns and general economic conditions (when they affect giving).

I offer more detailed instructions in Part Two.

Also have a look at Google’s directions and give it a try.

Thanks to Audrey Geoffroy, Data Analyst at University of Florida Foundation for mentioning to me that this gadget resulted from Google’s acquisition of Gapminder’s Trendanalyzer software, which was made famous in Hans Rosling’s TED talk (view below). Very entertaining!

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