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Insulation and Snow

When we bought our house it was entirely uninsulated. We insulated it in two phases:

  • When we put the dormers in, the parts of the house that were taken back to the studs got foam insulation. This means the back half of the house, the dormers, and the area above the third floor ceiling.
  • This summer we had insulation blown in everywhere else, except for one corner where there was more space and they used batts instead.

Here's a diagram, where red is foam, blue is blown-in, and green is batts:

One way to see how well this worked is to look at snow on the house. I don't have pictures from before we put in any insulation, but my memory is that the roof generally melted the snow rapidly by retaining very little heat. I do have pictures, though, from (1) after we had the foam but before we blew in insulation, and (2) today:

Left side:

Right side:

Overall, it looks to me like the left side is a lot better, but the right side, specifically the area where they used batts, isn't.

Here are those pictures again, with lines showing which parts of the roof have what kinds of insulation:

Left side:

You can also see that the (2x6, wood) rafters conduct heat better than the insulation, which gives us the lines running from the ridge down to the eaves.

Right side:

The foam and blown-in areas involve insulating the underside of the roof, while the batt area involved insulating the interior walls and floor. Specifically, the batt area is a triangular region of empty space, 5ft tall and 5ft deep, running along the house. They (said they) insulated where that area met the rest of the house, leaving the parts that touch the outside uninsulated. This should work: the remaining empty space will be external temperature, and we shouldn't have much air or heat making it into the empty space from the rest of the house.

Looking at this picture, I think there's either a large air leak from the rest of the house into the empty space, or something very wrong with the batts in one of the places. Does that sound right?

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Open-Hand Catan

The rules of Settlers of Catan say "each player keeps their resource cards hidden" but in my experience the game is much more fun if resource cards are visible:

  • Much less time spent proposing trades. If I really want a brick and don't remember whether anyone has one, I might make several offers in turn ("one sheep ... two sheep ... three sheep ... three sheep and a wheat, come on!") needing to pause between each one to give people time to react. With open hands you're never proposing incompatible trades.

  • Much more fluid trading. Having open hands means other players can model each other better, and so are more likely to propose trades that others will find acceptable. I need a brick for a settlement, and I can see that if you had one more wheat you could build a city, so I offer a brick for a wheat.

  • More trading overall. The previous two points remove friction from trades, which means more trades happen. More trades means, effectively, richer players, which speeds the game up beyond just the time gained from not proposing incompatible or unacceptable trades.

I find open hands enough better that if I'm playing with a new group, even if I can't convince them all to play open hands people are usually ok with me having my hand visible. I find I end up doing more trades than other people because it's easier for people to trade with me, and trades help you a lot. There are disadvantages, like someone moving the robber has a better sense of what they could get if they played it on me, but I don't think it hurts me overall.

(I got into playing open-hand at Swarthmore where this was the standard way to play. Local legend had it that this was adopted to re-level the playing field after a student with a very good memory (hi Fred!) was able to mentally keep track of exactly what was in everyone's hands.)

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A calming strategy

When Lily (3.5y) is very upset about something fixable, here's something I've found helpful:

L: Papa I don't want this cup! This cup is blue! I don't like this blue cup!
My first impulse is just to fix the thing:
J: That's ok Lily, here's an orange one.
If she's not very worked up then this will often work fine. She takes the orange cup and moves on with her life. But if she's pretty upset then I find this tends to continue like:
L: That's not what I wanted! I don't want that cup! That cup is too small! I want a cup like my blue cup but orange!
I think what's happening here is I haven't given her time to calm down. She gets the new cup, still feels sad and angry, and finds something else to be sad and angry about. And now she's gotten set on a kind of cup I don't have for her.

What I've found works better is moving slowly and being collaborative:

J: What would be better?
L: I want a different cup!
J: Let's go over and look at the cups and you can pick one out.
L: [chooses an orange cup]
This gives her feelings time to dissipate, so that by the time she has the new cup she's ready to enjoy life again. She's also the one making the decision, so I have buy-in from her and we're less likely to go in a direction that isn't fixing the underlying problem.

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What should "counterfactual donation" mean?

Sometimes people will describe a donation as "counterfactually valid" or just "counterfactual". For example, you might offer to donate a counterfactual dollar for every push-up your team does. [1] The high level interpretation is that you're doing something you wouldn't have done otherwise. For example, if you hire a mason to repoint your wall it's definitely not something that would have just done on their own, while when charities offer donation matching your donation doesn't generally affect how much of the matching funds the charity receives. The former is fully counterfactually valid while the latter isn't counterfactually valid at all.

Say I offer to make a counterfactual donation of $50 to the Against Malaria Foundation (AMF) if you do a thing; which of the following are ok for me to do if you don't?

  1. Donate $50 to the AMF.
  2. Donate $49 to the AMF.
  3. Donate $50 to the AMF tomorrow.
  4. Donate $50 to another long-lasting insecticide treated anti-malaria net distribution charity.
  5. Donate $50 to another of GiveWell's top charities.
  6. Donate $50 to another group that is commonly supported by EAs.
  7. Donate an extra $50 to the AMF next year.
  8. Donate an extra $50 to the AMF next year, not because of intentional dishonesty, but just because not having given $50 this year I happen to have more money available next year when it comes time for me to figure out how much to donate and at that point I still think the AMF is a good choice.
  9. Spend an extra $50 on myself (go out to eat when I wouldn't otherwise, etc).
  10. Light a $50 bill on fire. [2]

The first example is exactly what counterfactual doesn't mean here: I'm just going ahead and doing my half of the deal whether you do your half or not. The last example is pretty clearly counterfactual. Which of the ones in between are ok?

I would draw the line as allowing only the last two. The goal of clarifying that something is counterfactual is to allow the other person to reason as if they're causing the thing to happen. On the other hand, maybe that's an unreasonably high barrier, and if we decide that's what "counterfactual" means no one will be able to use the term for anything, so we should adopt something weaker?


[1] This is philosphy-inspired EA-jargon, and as jargon I'm mixed on it but I think it's helpful to think about what we've been using it to mean and what it should mean.

[2] We could add a final one here, something like I donate $50 to a malaria promotion organization, but that's extortion. (For some reason this is commonly referred to as 'blackmail', even though it doesn't involve threats to reveal information.)

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Startup Equity

The standard way to compensate startup employees is to pay a below market salary, and then make up for it with stock options. If the company succeeds the employee can exercise the options, turning them into liquid stock, while if the company fails they're not worth anything.

Consider a different model: companies sell the stock they would have been granting options for, raising more cash, and then use that to pay employees market rates. It seems to me that either I'm missing something (quite possible; leave comments!) this is a much better model and employees should push for it.

Possible reasons for the current system: more...

Forked Brass

I was playing around with some PVC with my kids, and made something I can't figure out the physics of:

more...

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