Quick and Dirty Metric for Determining Probability of Customer Being Active

July 15th, 2008 by Chris Herrick

 

One of the toughest problems facing organizations with many customers and large numbers of transactions is determining when a customer has left the company for good. Unlike contractual businesses where the customer is locked in for a given period of time, most companies have to make educated guesses about whether or not a customer is worth spending their marketing dollars pursuing.  While there are complex data analysis models that can be more than 80% accurate in predicting when a customer will buy next, many times a quick and dirty calculation can give your marketing executive a better indication of who to contact in the future.

We sometimes use the following metric to give an initial suggestion of whether or not a customer is still active in a given period. To clarify, period here can mean any observable time length - days, weeks, months, even years can work depending on your type of business and how long your typical customer stays engaged:

Probability (Active) = (T/N)n

where:

T = last period when the customer made a purchase

N = total periods in your observation time

n = total number of purchases during observation time

To give you an example of how it’s used, let me take the following example out of the book Managing Customers for Profit: Strategies to Increase Profits and Build Loyalty by V. Kumar (highly recommended) to illustrate the power of its simplicity. Let’s say I have two customers with the following purchasing pattern over a twelve month time horizon (X’s indicate when a customer made a purchase):

 

1

2

3

4

5

6

7

8

9

10

11

12

Customer 1

X

 

X

 

X

 

X

 

 

 

 

?

Customer 2

 

 

 

X

 

 

 

X

 

 

 

?

The probability for each customer to purchase in time period 12 is calculated as follows:

Customer 1 = (7/12)4 = 11.58%

Customer 2 = (8/12)2 = 44.44%

The initial results may seem counter-intuitive - why does Customer 1 have a lower chance of purchasing again when he/she has 4 purchases in the observation time while Customer 2 only has 2 purchases? Well, as you can see from the table, Customer 2 appears to buy every 4 months and is poised for another purchase in month 12 while Customer 1 was purchasing every 2 months, but hasn’t made a buy in over 5 months so is unlikely to buy again in month 12.  Nice, huh?

While the above metric doesn’t take into account all important information, it does provide a fast and easy way for marketers to get a better indication of whether a customer should be put into the active marketing group or the re-activation group.

| More

Tags: ,


Add Personalized Product Recommendations to Your eCommerce Site

Istobe is a powerful recommendation engine that makes it easy to add recommendations to your eCommerce site. How powerful? Shoppers who click on Istobe recommendations spend 20-50% more than the average visitor.


One Response to “Quick and Dirty Metric for Determining Probability of Customer Being Active”

  1. Hari Says:

    I find an error in your calculation. Move customer 2’s X from the 8th month to the 5th month, and your calculations would still be the same. While in-fact, intuition says that the model should give a lower value for the probability in this case.

    Please revise, using other variables like the time period between purchases.

Leave a Reply