This year I was in charge of marketing for EA Global. This gave me some useful insights into the EA community and why it's growing rapidly. I'm planning to do a full write-up in the future, but two insights are worth sharing now.
More than half of EA Global applications were due to referrals
Of the 2,152 applications that we received for EA Global this year, around 55% of them applied because of someone else in EA. This includes 689 applications through the nomination system and 486 that were caused by "someone involved in EA." As someone who spent the list 3+ months of my life trying to get applications for EA Global, it's very interesting that the EA community itself is still the best marketing tool we have.
EA's are willing to tell others about EA
As part of registration, we asked the following question:
How likely is it that you would recommend Effective Altruism to a friend or colleague?
This is the so-called Net Promoter Score (NPS) question popularized by Bain and Company in the early 2000s. NPS is a popular method of measuring customer loyalty. Answers are given on a 0 to 10 scale with 0 being "not at all likely" and 10 being "extremely likely." A brand's score is determined by taking the percentage of 9s or 10s (promoters) minus the percentage of 6s or below (detractors) while ignoring 7s and 8s (neutrals). A score of +50 is considered excellent. Apple scores in the high 60s to low 70s.
Out of 438 respondents, our average score was 8.53 with an NPS of +45. 42% of people gave EA a 10 out of 10. This is in line with a similar question asked of EAGx attendees which showed an NPS of +45 across 52 respondents.
NPS has a number of flaws (read the Wikipedia page for details) so I wouldn't take it too seriously. Yet, the NPS score coupled with the referral evidence suggests that as a brand EA has a very dedicated fanbase that is willing to promote the brand.
Potential implications
We might be able to draw a few implications from this:
Being More Welcoming
One popular topic of conversation is how to make EA more welcoming. And, of course, we should strive to be more welcoming. Yet, if EA is already building a highly loyal community willing to promote EA, then perhaps this isn't one of the most pressing problems facing EA.
EA is too cultish
One reaction that people sometimes have to EA is that it seems "cultish." Seeming cultish is clearly a bug and something we should fix. Yet, the perception probably results from a combination of high brand loyalty and a set of ideas that sometimes result in radical life change. Put this way, it seems more like a feature than a bug. Indeed, some of the best brands have "cultish" following (Apple comes to mind).
Edit: Howie's post below has updated me to think that we can't infer much about the welcominess of EA or whether EA is too cultish on the basis of the data here. At best we might be able to conclude that EAs think their friends and colleagues will like the community, but this doesn't tell us much of what they'll think of the community once they've interacted with it.
At EA Berkeley, we have members who came through people telling their friends, and people who we got essentially by picking students at Berkeley near-randomly (but selecting for altruistic tendencies). (TL;DR: These students get involved either through a speed Giving Game or by seeing an ad for our course on EA, rather than through social networks.)
The members who came from people telling their friends fit the standard EA demographic, as you might expect -- mostly male, and all STEM (and mostly Comp Sci). Let's call them group A.
Meanwhile, the students who we got near-randomly, selecting for altruistic tendencies, are more likely to be female and have essentially no specific major. Let's call them group B.
Now, group A forms a much larger percentage of EA Berkeley, so they tend to determine topics of conversation and group activities. We've talked about NP-completeness, video games, the popularity of certain CS professors, etc. These are great topics of conversation for group A, even if the individual members don't know each other. Note that they have nothing to do with EA. However, there are usually one or two members of group B at these events, and inevitably they are quiet and don't interact much with everyone else.
With that sort of dynamic, it's not surprising to me at all that we tend not to get very many active members from group B. When I say "being more welcoming", I mean not talking about NP-completeness, video games and popularity of CS professors, and instead talking about topics that everyone could be a part of. This seems like an important change that will directly lead to more retention of members in group B, which in turn seems important to me because it increases the diversity of EA.
Note that "EA is already building a highly loyal community willing to promote EA" is perfectly compatible with this view -- that loyal community is group A.
Also, as a result I strongly disagree with "presumably, similar behaviors work with a wide range of people" -- the behavior of "talking about NP-completeness, etc." works great with CS majors but not others.
I mostly agree with your last paragraph, except that I think "being more welcoming" is the external pressure that would help EA become more diverse (through the mechanism outlined above).
I would like to offer a contrasting view point from our experiences at EA McGill. Our members seem to be more often in subjects like Economics and International Development and since McGill has a high female to male ratio, they also tend to be women.
I actually happen to be one of the few CS students. From what I can tell this difference is primarily due to the founder effect, as our founders were in more economics like subjects, and due to the different demographic make ups of Berkeley and McGill.