Below are some of the questions I find interesting, mostly outside of heavy industry and machine learning. Relevant reading recommendations always welcome.

• What are the externalities of income inequality? What is the marginal social cost of inequality? Can this be quantified?

  In spite of some research on the subject, I haven't found a source that quantifies the costs of income inequality. It seems that most policy recommendations are based more on "animal spirits" than on estimated costs.

  I'd be interested in the list of negative externalities: social unrest, breakdown of institutional trust, unproductive behaviors, etc.

• What are the marginal social costs of greenhouse gas emissions?

  Working in energy, this question is often top of mind. What is the ideal tax on GHG emissions? I have seen some brilliant efforts to quantify the discount rate over very long periods, based on relative pricing of leasehold and freehold properties in the UK, but I have yet to find research that quantifies with present value of the GHG emissions.

  In my view, with the long term discount rate approximated, we only need to know the approximate marginal social cost of a tonne of carbon-dioxide emissions to implement an optimal tax policy. Unfortunately, this seems to me an unusually difficult question: how do emissions affect property values in Amsterdam vs. Fairbanks, Alaska? Do carbon dioxide emissions in New Zealand affect property values in Spain? Over what period will these property value adjustments take place due to emission? Climate systems are difficult to model!

• What is the single policy change in the US that would create the most value?

  Value here defined in the basic economics sense of the word, namely, the price an individual is willing to pay, less the price at which the provider is willing to provide such a service, then aggregated across all units of the goods or services delivered. For example, although citizens may have a high willingness to pay for comprehensive healthcare services, the price at which providers are willing to provide that care may exceed the willingess to pay.

  What is the policy adjustment that could be made to drive the most value? Does it have to do with retirement accounts, taxes, education, healthcare, or something else? How might you attack this problem and identify a solution? To a first order approximation, the policy change should be Pareto efficient, that is, not making any individual worse off.

• What countries are best in the world in each major policy area?

  I'm particularly curious about healthcare, the eradication of poverty, technology development, schooling, retirement programs. Generally, which countries are best in class for all major public policy issues? Can these policies be replicated in the US, or are they only possible because of idiosyncratic factors? I would love to take a field trip to each of the chosen countries to learn more about what makes them so effective. What measures should we use for effectiveness?

• What thirty year period in world history generated the most real wealth on a per capita basis? What about the highest level of per capita growth?

  Thirty years is semi-arbitrary—long enough to avoid the impact of business cycles, including recoveries. What were the drivers of growth in these periods? What are we missing today? What could be replicated?

• What concepts or practices can be implemented to free up the most personal time?

  As I get older, I appreciate time more and more as the binding constraint. I'd imagine the answers are specific to each individual, but what are some simple practices to eliminate poorly-spent time or create more time generally. Where is time mis-allocated? What steps can I take to free up more of it?

  For one week, I used a time tracker to log every minute of my day, and was surprised how much time was spent in-between tasks (traveling between meetings, for example) and how difficult it was to set four hours of interrupted work.