This document discusses optimizing content for virality through A/B testing on websites and social media. It defines virality as organic growth through users sharing with friends. The key to virality is improving the action, invite, and response rates in the viral loop. Case studies show how A/B testing petition pages, share pages, and language can increase a campaign's virality ratio and drive significantly more viral growth and new users. Without optimization, one campaign was estimated to generate 22,000 fewer actions and 15,700 fewer new users.

1. BEST PRACTICES IN DIGITAL ANALYTICS:
Optimizing For Virality
With Website And
Social Media A/B Testing

2. OUR STORIES OF SELF
Jim Angelica

3. WHAT IS VIRALITY?
• Often used, poorly understood:
 “Make me a viral video!”
 “There’s a viral campaign happening on Twitter”
 “Social media goes viral on Capitol Hill”
• Virality measures organic growth, not overall popularity
• Determined by how much your users are sharing with friends

4. 0
100
200
300
400
500
600
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Users
Time
Sub-Viral
0
5000
10000
15000
20000
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Users
Time
Viral
WHAT IS VIRALITY?
• Virality Ratio – average number of new people each user recruits
• Definition of “viral”: Virality ratio greater than 1 – explosive growth
• Virality ratio less than 1 is sub-viral – growth is limited

5. VIRALITY EXAMPLES
VIRALITY
RATIO
INITIAL
USERS
(GEN 1)
RECRUITE
D USERS
(GEN 2)
RECRUITE
D USERS
(GEN 3)
USERS AFTER 10
GENERATIONS
0.01 5,000 50 1 5,051
0.1 5,000 500 50 5,556
0.5 5,000 2,500 1,250 9,990
0.9 5,000 4,500 4,050 32,566
1.1 5,000 5,500 6,050 79,687

6. Action
Invite
Response
Action Rate x Invite Rate x Response Rate =
Virality Ratio
THE VIRAL LOOP
• Users take action
• Users invite friends
• Friends respond, become users
• Repeat

7. IMPROVING VIRALITY
• "Ok, I understand what virality is -- but how can I increase it?"
• Remember: Virality Ratio = Action Rate x Invite Rate x Response
Rate
• Improving rate of any step improves virality ratio by same amount

8. A BRIEF INTRODUCTION
TO A/B TESTING
• Q: You have two ideas for language on a web page –
which one do you choose?
• A: Both!
• Steps to run a webpage A/B test:
– Create several different versions of the web page
– For users coming to page, randomly show one version
– Record if visitor takes the action
– Calculate conversion rate (average # of actions per
visitors) for each version – highest conversion rate is best

9. 29% increased
conversion rate
WEB PAGE A/B TESTING

10. +140% share
recruitment rate
SOCIAL MEDIA A/B TESTING

11. STATISTICAL SIGNIFICANCE

12. VIRALITY OPTIMIZATION
EXAMPLE #1
• New campaign has virality ratio of 0.1 – viral actions increase total
action count by 11%
• Virality loop optimizations:
 Optimize action page -> 20% higher action rate
 Use optimized share page -> 60% more sharing to friends
 Test share language -> 35% higher click rate
• New virality ratio: 0.1 x 1.20 x 1.60 x 1.35 = 0.26
• Viral actions increase total action count by 35%

13. • New campaign has virality ratio of 0.4 – viral actions increase total
action count by 67%
• Virality loop optimizations:
 Optimize action page -> 20% higher conversion rate
 Use optimized share page -> 60% more sharing to friends
 Test share language -> 35% higher click rate
• New virality ratio: 0.4 x 1.20 x 1.60 x 1.35 = 1.04
• VIRAL CAMPAIGN
VIRALITY OPTIMIZATION
EXAMPLE #2

14. CASE STUDY
CREDO ACTION PETITION:
“STOP THE MONSANTO PROTECTION ACT”

15. CASE STUDY
CREDO ACTION PETITION:
“STOP THE MONSANTO PROTECTION ACT”

16. RESULTS
• The average petition gets less than 2% of names from social
sharing
• CREDO received 13% of signatures from social sharing, resulting
in 25,000 new names on their list
• How did they do this? CREDO optimized their petition page, used
pre-optimized share pages, and optimized their share language
asks

17. CASE STUDY
CREDO ACTION PETITION:
“STOP THE MONSANTO PROTECTION ACT”
OPTIMIZED PETITION PAGE
• Multiple rounds of A/B testing have improved the action rate for
the petition page where people add their name

18. OPTIMIZED SHARE PAGE
• CREDO used a pre-optimized ShareProgress share page for the
petition to increase the sharing rates for signers

19. OPTIMIZING SHARE LANGUAGE
• CREDO tested share language to turn more shares into viral
actions
• One Facebook language variation performed 63% better that the
first version, increasing overall viral actions by 35%
Facebook Title
Shares Driving Action /
Total Shares
Success Rate Improvement
Monsanto shouldn’t be
above the law
341/1041
32.8% (±2.9%)
--
“One of the most outrageous
special interest provisions in
years”
322/962
33.5% (±3.0%)
2.2%
Tell the Senate: Repeal the
Monsanto Protection Act
458/972
47.1% (±3.1%)
43.8%
Sign the Petition: Repeal the
Monsanto Protection Act
555/1037 53.5% (±3.0%) 63.4%

20. OVERALL RESULTS
• Virality loop optimizations:
 Optimize action page -> 20% higher conversion rate
 Plug in ShareProgress share page -> 50% more sharing to friends
 Test share language -> 35% higher social conversions
• Result: Virality ratio of 0.135 (13.5% of actions from social sharing)

21. WHAT WOULD HAVE HAPPENED
WITHOUT OPTIMIZATION?
With Optimization:
Virality ratio: 0.135
35,000 actions from social
25,000 new-to-list
Without Optimization (estimated):
Virality Ratio: 0.056
13,000 actions from social – 22,000 fewer
9,300 new-to-list – 15,700 fewer

22. QUESTIONS?

23. VIRALITY CHALLENGE
• http://www.shareprogress.org/virality-challenge/
• You need to optimize the action page, share page, and social
sharing content to make your petition go viral.
• Only one combination of parameter choices will result in a viral
campaign!
• Check your statistical significance at
http://www.thumbtack.com/labs/abba/.