A Google Tag Manager recipe: how to set up a/b tests, and analyze the results

1. SET UP (AND
ANALYZE) YOUR
A/B TESTS LIKE A
BOSS
USING THE GOOGLE TAG MANAGER
JULES STUIFBERGEN – CONVERSION HOTEL 2014

2. TOPICS FOR THIS
SESSION
• Two ground rules
• The added value of commercial tools
• What type of A/B tests am I talking about
• Can we replicate this functionality (using GTM)
• For free
• For kicks
• Because we can!
• Let’s find out!

3. A/B TESTING RULE 1:
RANDOMNESS
Visitors enter your experimentation zone
They’re assigned to a
variation (A or B)
randomly.
Then, they’re part of your
experiment.

4. A/B TESTING RULE 2:
CONDITIONS STAY THE SAME
Visitors are in the same condition, always.
Condition A
Condition B

5. THE ADDED VALUE OF
COMMERCIAL TOOLS
Optimizely VWO

6. THESE TOOLS DO 2
THINGS REALLY WELL
UGLY code Fancy GUI

7. WHAT TYPE OF TESTS
AM I TALKING ABOUT
• Same URL / page group
• Content manipulation with Javascript / jQuery
Meet jQuery. A big fat
Javascript library

8. LET’S REPLICATE THE
LOGIC
Pseudo code for a visitor entering the experiment
1. Does the visitor have a valid cookie?
1. Yes: set the condition variable w/ cookie value
2. No: Roll a dice and assign condition A or B
2. Store the condition in the cookie
3. Load the code for A or B
1. Javascript / jQuery code
2. Google Analytics code

9. READY TO CODE
YOUR TAG?

10. DETAILS: CONFIG
This code allows
endless amount of
variations.
One cookie per test

11. DETAILS:
ASSIGNMENT
In words:
If the cookie value is not in the
list of the variation names:
Pick a random variation.

12. DETAILS: COOKIE
Set the cookie, always.
This makes sure the cookie is renewed for 90 days
(code stolen from the interweb)

13. DETAILS: THE FUN
STUFF
This is where the
GTM magic begins.
abtest macros for
category, action and
label (from datalayer)

14. DETAILS: THE FUN
STUFF
This is where the
GTM magic begins.
Built-in event macro,
to trigger the action

15. RULE NR. 1
Fires on all abtest
events

16. MEASURE LIKE A
BOSS

17. RULE NR. 2 (AND 3..)
Fires variation
code

18. CODE LIKE A BOSS

19. OR.. CHEAT LIKE A
BOSS
Steal (and clean)
optimizely’s code using
the “edit code”
functionality

20. START YOUR
EXPERIMENT
This goes in a Tag
Activated by a
Rule

23. DEBUG YOUR
CONTAINER VERSION
LIKE A BOSS

24. WELCOME VISITORS..
http://datadatadata.nl/ch2014.html

25. AND ANALYZE THE
RESULTS
Use Google Analytics User
Segments on Events

26. YOU WIN!

27. THANK YOU
Jules Stuifbergen
@zjuul