I've been thinking about what research projects I should work on, and I've posted my current view. Naturally, I think these are also good projects for other people to work on as well.
Brief summaries of the projects I find most promising:
- Elaborating on apprenticeship learning. Imitating human behavior seems especially promising as a scalable approach to AI control, but there are many outstanding problems.
- Efficiently using human feedback. The limited availability of human feedback may be a serious bottleneck for realistic approaches to AI control.
- Explaining human judgments and disagreements. My preferred approach to AI control requires humans to understand AIs’ plans and beliefs. We don’t know how to solve the analogous problem for humans.
- Designing feedback mechanisms for reinforcement learning. A grab bag of problems, united by a need for proxies of hard-to-optimize, implicit objectives.
Some things can be done by imitation based on our current understanding (and will get better as machine learning improves). The interesting part of the project is figuring out how to do the trickier things, which will require new ideas.
It's not clear that imitation impairs your ability to generalize to new domains. An RL agent faces the question: in this new domain, how should I behave to receive rewards? It has not been trained in the domain, but must learn to reason about the domain and figure out what policies will work well. An imitation learner faces the question: in this new domain, how would the expert behave / what behavior would they approve of? The two questions seem similar in difficulty, and indeed you could use the same algorithmic ingredients.
It's also not clear that it's relevant if a task involves thinking about cost functions, models, simulation, calculation, etc... These are techniques one could apply either to achieve a high reward, or to produce actions the expert would approve of / like / do themselves. You might say that at that point these rich internal behaviors must be guided by some non-trivial internal dynamic. But then we will just have the same discussion a level lower.