Distance does not matter, travel time does. As does pricing because prices for train and plane are basically unrelated and because I'm currently a student and don't have much money. My decision mostly depends on the events around my travel – sometimes I have to fly to make it in time. This means I find it difficult to give a simple function, so let me give some examples:
• I currently live in Edinburgh and I fly to visit people in Germany or the Netherlands over the weekend. On the other hand, I will move back to the continent in September and will visit the LW community weekend "on the way". This will involve a travel time of around 25h over a period of 45h (13.5h train, 6h ferry, 4h cycling, 1h waiting, ~0.5h local transport). If I took a plane, it would cost around the same and I'd spent 10h (1.5h flight, 2h security/waiting, 1.5h local transport, 5h packing and unpacking bike + getting the packaging in the first place). EDIT: Without the bike, the times would be 19h (train through the tunnel) vs 5h and I'd fly.
• There is a reasonable probability that I'll be living in Switzerland soon, in which case I'm planning to do family visits by ~9h train instead of ~5h flight+transport. That is because I'm expecting it to be possible to do "home office" in the train.
• I really like night trains. I count night travel as 2-3h time investment due to reduced sleep quality.
• I prefer flying + airport shuttle over driving a car for the same total time if I'm the only driver. If this is a road trip with like-minded people and we share driving responsibilities, up to like 24h of driving seem okay during holidays. I'd probably prefer the plane once I have a job.
In short, I'm wondering what place/group/organisation/activity could do for rationality in Europe what Berkeley does for rationality in the US?
Soon, we'll have LWCW in Berlin, which I hope will be an occasion to do some networking among people who think seriously about developing rationality communities. But in the meantime, let's do some brainstorming.
Important note: in comments to this post, please use only consequentialist language. For example, say "If we decided for the base to be on Malta, then X would happen" instead of "I think it should be in Malta, because..."
Of course, share anything else that you think is relevant to the topic.
Also, see you all in Berlin :)