Spaced repetition is optimal for recalling factual information. It won't necessarily teach you anything that you haven't already learned. It helps you retain knowledge, and won't necessarily help you develop skills. But, within the domain of factual information that you can already comprehend, spaced repetition systems are pretty optimal. So, if you want to train your brain on a bunch of Spanish-to-English sentence translations, or stock market tickers, or definitions, or sample questions, you should use something like Anki. 

Once you start using spaced repetition, you learn that one of the biggest limits is the card-making process. Making your own cards is time-consuming, although experience will make you much faster. Experience will also teach you what makes a better card. The 20 Rules of Formatting Knowledge pretty much spells it out for you, but I still had to make my own cards, find the sticking points, and edit them until I got a good sense for proper context and suitably short, distinct answers. 

You can find other people's shared decks and skip the card making process yourself, but not without some new problems. First, you are going to learn more making the cards yourself than studying someone else's. If it's subtle material, you can make cards that fill in the gaps in your particular understanding. But if someone else studies something and makes cards to fill in their own gaps, that means that what you're studying may not cover material that you don't know you don't know. It would be nice if everyone's shared decks were a completely thorough treatment of the material, but, alas, it is not so. And the only way that you can tell is by comparing the deck and the material during your own studying.

Shared decks also just aren't all that good sometimes. Someone, I can't recall who, wrote a script to scrape the entire LW wiki and then cloze-delete the title from the article. I appreciate the idea of SRSing the LW wiki, and scripting the whole thing was undoubtedly really efficient. However, the result was usually question and answer text hundreds of words long, with tables of content in the middle, and probably too many cards of insufficient value. 

Despite their problems, I think that shared decks have way more potential than their current use suggests. A well-crafted deck that gives its subject matter a thorough treatment could be more valuable than a textbook, and about as difficult to compose. But, looking at some of the best Anki decks I've come across, it will likely take more than one person to get such a deck off the ground. 

Anki's .apkg files are sorta unwieldy to edit collaboratively, because there's not really a way to merge edits from multiple contributors. Luckily, we can export and import decks as text, and use version control like GitHub to do the same thing. With a GitHub-hosted collaborative deck, a team of people studying a textbook, like Thinking and Deciding, could all make flashcards as they go, add them all to the same deck, remove redundant cards, standardize the layout, tag cards appropriately, and share them with whomever else comes along. Then, anyone else who wants to study the textbook has a high-quality Anki deck to use in conjunction, and if they know how a question can be asked better, or if they find an error, or if the seventh chapter didn't really get much coverage, they can contribute to the deck, too. 

This huge list of material put together by Louie Helm should be Anki-fied. Hopefully we can unite the efforts of many autodidacts and start to curate decks for each of the areas covered. Maybe a group of friends is about to work through a course on Quantum Computing or Set Theory. The rest of LW would benefit from their work making flashcards, but especially so if they leave the project open to collaboration. 

So, the things needed to move forward:

• Someone learned in IP tell me what kind of licensing or copyright applies here. Should people post these with a Creative Commons or a GPL? Obviously we don't want to start plagiarizing or copyright-violating in the process of making this work. We don't want to abscond with other people's decks and start building on them, I think.
• If you're about to tackle an area of study on the MIRI courses list, make a GitHub repo for it.
• If this interests you in the slightest way, please contact me. iconreforged@gmail.com 
• I'm working through the dull details of hosting an Anki deck in text form on GitHub myself with the copious number of Russian flashcards I made in three semesters of Russian classes. Hopefully that can provide some kind of template. If I'm feeling ambitious, I might start a Heuristics and Biases deck based on Thinking and Deciding.

I belong to a group at my university that organizes a backpacking trip for incoming freshmen in the two weeks before orientation week. This organization, which I will refer to as HIKE (not the real name), is particularly interesting in terms of group design. Why? It is approximately 30 years old, is run entirely by current students, and brings together a very large group of people and knits them into a largish community. Pretty much everyone involved  agrees that HIKE works very well. During my involvement (I was a participating freshman, and I have since become staff) I have continually wondered, why is this group so much more fun than any other group I've been a part of?

It's also particularly effective. Leading ~80 incoming freshmen, who have no current friends, and who know no one, and who don't generally have any backpacking experience, into the woods for two weeks, is no easy task. HIKE manages its own logistics, staff training, and organization, entirely with student volunteers who staff the trip, with little to no university interaction. (We get them to advertise our trip, and they generally permit us to continue to exist.) It takes some dedication to keep this rolling, and I have seen other campus groups completely fail to find that kind of dedication from their membership.

While it's not a rationalist group, it seems to have stumbled upon a cocktail of instrumentally rational practices. 

HIKE uses an interesting process of network homogenization. When staff members (who have generally been on several trips before) are assigned crews, staff members fill out "Who Do You Know?" forms, on which you rank how well you know other staff on a scale from 1 to 5. The people in charge of making groups, usually Project Directors, then group staffers based on how well you don't know other staff. You usually staff a trip with people that you haven't gotten to know very well, and then get to know them. Because of this process of strengthening the weakest bonds, HIKE is able to function as a relatively large social group, even across graduation classes and around existing cliques.

As far as actual interaction, HIKE involves a lot of face time with your crew of 10 freshmen and your co-staffers. There aren't really any breaks (with the exception of solos, see below) and you are hiking, eating, and chatting together for approximately 225 hours (15 waking hours in a day * 15 days). I had 13 hours and 40 minutes of class a week the Spring 2013 semester. HIKE is approximately 7+ weeks of class at that rate.

One of the more beloved HIKE traditions is the solo, where the hiking leaders pick a spot with plenty of isolated spaces, and the participants can choosee to spend ~24 hours alone and, optionally, fasting. It's a novel experience, and people like the time to rest and reflect in the middle of a very social, very intensive hiking trip.

My suspicion for why this all works is that HIKE very closely simulates a hunter-gatherer lifestyle. You travel in ~10 member groups, on foot, carrying your food, on mountain trails. You spend your every waking hour with the crew. The 2-3 hiking leaders are there to facilitate only (read: perform first aid if necessary, guide conversation, teach outdoor skills if necessary, and nudge the group if they get off track), and all decisions are made by consensus (which isn't an all-purpose decision making process, but is very egalitarian, and helps the group gel).

Maybe I'm just praising my friend-group, but I feel like I stumbled into a particularly strong group of people. We all feel very well-connected and we feel a lot of commitment to the program. My experience with other college groups has been that members are pulled apart by other commitments and a lack of familiarity with other members, and HIKE seems to avoid that with a critical mass of consecutive face time. We manage to have continuity of social norms across the years, but a great deal of flexibility (no one remembers what happened 4 years ago, and some traditions disappear and others cement themselves as ancient and hallowed despite being only two years old).

I'm interested in hearing any thoughts on this, and any relevant experience with other groups, ideas for testing cross-application, requests for further elaboration, etc.

This study seems to show that minocycline helps to resist placing too much trust in attractive women.

Recently, minocycline, a tetracycline antibiotic, has been reported to improve symptoms of psychiatric disorders and to facilitate sober decision-making in healthy human subjects. Here we show that minocycline also reduces the risk of the 'honey trap' during an economic exchange. Males tend to cooperate with physically attractive females without careful evaluation of their trustworthiness, resulting in betrayal by the female. In this experiment, healthy male participants made risky choices (whether or not to trust female partners, identified only by photograph, who had decided in advance to exploit the male participants). The results show that trusting behaviour in male participants significantly increased in relation to the perceived attractiveness of the female partner, but that attractiveness did not impact trusting behaviour in the minocycline group. Animal studies have shown that minocycline inhibits microglial activities. Therefore, this minocycline effect may shed new light on the unknown roles microglia play in human mental activities.