# CoolData blog

## 17 January 2010

### Proving ‘event attendance likelihood’ actually works

Filed under: Event attendance, Model building, Predictive scores, skeptics — Tags: , , , , — kevinmacdonell @ 6:56 pm

In an earlier post I talked about what you need to get started to build an ‘event attendance likelihood’ model. Today I want to provide some evidence to back up my claim that yes, you can identify which segment of your alumni population is most likely to attend your future event.

To recap: Every living, addressable alumnus/na in our database is scored according to how likely he or she is to attend an event, whether it be a President’s Reception or Homecoming, whether they’ve ever attended an event or not.

The scores can be used to answer these types of questions:

• What’s the top 30% of alumni living in Toronto who should be mailed a paper invite to the President’s Reception?
• Who are the 50 members of the Class of 2005 who are most likely to come to Homecoming for their 5th-year reunion?

I built our first event-attendance model last summer. As I always do, I divided all our alumni into deciles by the predicted values that are produced by the regression analysis (the ‘raw score’). The result is that all alumni were ranked from a high score of 10 (most likely to attend an event) to 1 (least likely).

At that time, alumni were sending in their RSVPs for that fall’s Homecoming event. Because I use only actual-attendance data in my models, these RSVPs were not used as a source of data. … That made Homecoming 2009 an excellent test of the predictive strength of the new model.

Have a look at this chart, which shows how much each decile score contributed to total attendance for Homecoming 2009. The horizontal axis is Decile Score, and the vertical axis is Percentage of Attendees. Almost 45% of all alumni attendees had a score of 10 (the bar highlighted in red).

(A little over 4% of alumni attendees had no score. Most of these would have been classified as ‘lost’ when the model was created, and therefore were excluded at that time. In the chart, they are given a score of zero.)

To put it another way, almost three-quarters of all alumni attendees have a score of 8 or higher. But those 10 scores are the ones who really stand out.

Let me anticipate an objection you might have: Those high-scoring alumni are just the folks who have shown up for events in the past. You might say that the model is just predicting that past attendees are going to attend again.

Not quite. In fact, a sizable percentage of the 10-scores who attended Homecoming had never attended an event before: 23.1%.

The chart below shows the number of events previously attended by the 10-scored alumni who were at Homecoming in 2009. The newbies are highlighted in red.

The majority of high-scoring attendees had indeed attended previous events (a handful had attended 10 or more!). But that one-quarter hadn’t – and were still identified as extremely likely to attend in future.

That’s what predictive modeling excels at: Zeroing in on the characteristics of individuals who have exhibited a desired behaviour, and flagging other individuals from the otherwise undifferentiated masses who share those characteristics.

Think of any ‘desired behaviour’ (giving to the annual fund, giving at a higher level than before, attending events, getting involved as an alumni volunteer), then ensure you’ve got the historical behavioural data to build your model on. Then start building.

1. Hello. I really like your blog, am learning lots. We are a Banner site as well. My question, is the event module in Banner used to track your event data? If no where does it live? We want to track events and I want to understand how the module is actually used.

Thank you
Debra Elliotte
Sr. Program Director
Development Services
Marshall University

Comment by Debra Elliotte — 21 January 2010 @ 11:47 am

• Hi Debra, and thanks … Yes, the event module is where we keep all our attendance data. It’s my understanding that not many schools make use of the module for event planning per se, but it’s the perfect place for tracking both RSVPs and actual attendance. For those tasks, it’s fairly easy to use, once you figure out how it works. I have a whole post on this very subject in the draft stage, so stay tuned!

Comment by kevinmacdonell — 21 January 2010 @ 12:10 pm

• Debra: I’ve just posted a tutorial for using Banner to track event attendance. Enjoy!

Comment by kevinmacdonell — 26 January 2010 @ 1:01 pm