Comments
Note: I have been involved with EA since 2-3 months only, so my ideas may not be accurate.
One approach is to target people involved in social issues who believe in some of the more popular EA concept(s).
Climate Change
Out of all the EA priority areas, climate change is arguably the most popular one (among non-EAs/general population).
Quite a few people (among non-EAs) work on climate change because they think it's the most pressing problem. They believe in some of the more well-known EA concepts like:
1. Using supply/demand concept to choose a social issue (aka neglectedness).
2. The fact that climate change needs to be fixed quickly while other social issues can be solved later also (similar to idea of existential risk).
On the whole, more involved groups appear to prioritise Global Poverty and Climate Change less and longtermist causes more. ~ EA 2019 Survey
However, I must point out that Global Poverty is ranked the most popular EA cause area, followed by Climate Change. I suspect this is due to a lot of people in the EA movement having joined recently, and taking some time to understand EA's ideas on cause prioritization.
Similarly, it may be efficient to target people who are involved in nuclear security (they share ideas of existential risk and sudden catastrophes are more important than catastrophes that build up over time).
Essentially, we are looking for people who are working on a particular social cause because of logical reasons. This greatly increases their chance of being a fit with the ideas of EA, since this approach captures both the effective and altruism aspects of EA.
Raising for Effective Giving targets the poker industry. The co-founders are poker players themselves and found that players embody the 'E' in EA. They propose that this audience tends to be more rational and logic than the general population. Their initial outreach strategy was to target players who have a pre-existing altruistic tendency, and get them to donate to more effective charities.
Not sure if that constitutes as data for your purposes, but they are an example of how they've targeted an audience that has seen some success in converting to EA.
That's pretty good for personal outreach, and I would agree that these assumptions can be helpful when trying to reach to people who will have a positive tendency towards EA.
Having said that, it's pretty unclear to me how you would translate that into ad targeting considering:
1. It's difficult to clearly target "rational and logical" people when you're trying not to approach a specific audience. I can obviously target engineers, mathematicians, and philosophy students, but that is excluding everybody else that is logical and rational and assuming others don't possess these characters. This can also decrease the variety of opinions and talents in our community even more. I might be more sensitive about this because i'm not that typical EA character (no academic background, not much of a technology guy).
2. The goal is to build the community, not necessarily finding people who will donate. This means that a lot of different people can be relevant for us and i'd like to open our reach but still keep it within a reasonable and logical audience.
Than again, sometimes you just can't win everything. Maybe it will be a good idea to target specific audiences with different posts, targeting each audience with content that is more palatable and interesting for them.