In a recent post I claimed you only need to know about twelve concepts in a given field to look like an expert compared to someone who only knows two or three concepts. A reader asked me to list the dozen concepts for building an energy-efficient house. I will take that challenge and list them here, compiled from my own research. Actually, I will list more than twelve for extra credit.

One caveat is that this list applies to a Northern California climate where air conditioning is more important than heating. Here's the list. My blog interface doesn't allow them to be numbered:

1. The Roof and windows are far more important to insulating the house than the walls. Your walls won't be the weakest link, and you don't need any exotic insulation type.

1. A radiant barrier for the roof is one of the best ways to keep heat from entering the house.

1. Windows are rated for their thermal efficiency. It makes a big difference if you get the most efficient ones.

1. Clay tiles, with lighter colors, are the best choice to reduce heat.

1. Common wisdom says an attic fan is great for removing heat. A better approach is to design the home so there is a natural chimney effect, taking advantage of the fact that hot air rises. All you need is a ground floor window you can open on the cool side of the house that has metal bars (for security) and a screen (for bugs). Then open an upstairs window and the air will circulate up and out without a fan.

1. Orient the house so there are relatively few windows on the hot western exposure. Shade the windows on the hot side of the house with trees that lose leaves in the winter, or shade the windows with a porch.

1. Add plenty of thermal mass inside the home to act as a natural heat regulator. That means concrete, stone, and tile.

1. Add solar panels, tied into the electrical grid. With rebates, and the cost wrapped into the mortgage, they are cash positive from day one. If you retrofit later, and they are not part of the mortgage, the payback takes maybe 20 years.

1. Water heating is a big component of your energy bill, but no expert can tell you the best solution. Common wisdom says tankless water heaters are best. But you might need a bunch of them, and they require maintenance. Some experts say continuous circulating water heaters are now nearly as efficient as tankless, without the maintenance hassle. New gas condensing types are just hitting the market, with even greater efficiency, but they don't have a track record.

1. If you talk to ten experts in this field, you will get ten different opinions for your home. Although rules of thumb are mostly consistent, every house is different, and without detailed engineering, which is impractical, there is still a lot of guessing.

1. Gas is cheaper than electricity.

1. Use Energy Star certified appliances when possible.

1. Keep your ductwork sealed (you can test for that), and insulated, and within the insulated envelope of the house as opposed to in a hot attic or cold basement.

1. Keep your AC compressor and condenser on the shady side of the house. It makes a big difference.

1. Take steps to reduce humidity inside the house to make it more comfortable during hot weather. For example, don't have houseplants, and use your bathroom exhaust fan when showering.

1. In this climate, assuming you insulated properly and managed the sun exposure, your best choice for a heating unit is a standard forced air type, engineered so it isn't too big for the job. The more exotic heating solutions such as geothermal only make sense in more extreme climates.

1. Small houses are more energy efficient than big houses. Duh.

1. Use LED or compact fluorescent lighting when practical.
   

Your first impression of this list is that it's mostly obvious stuff and you assume builders are doing it already. But I am writing this from my office inside a newish townhouse (six years old) that violated most of the concepts on the list. All I have going for me is Energy Star appliances, compact fluorescent lights,  and no house plants.

If you remember these concepts, you will know more about home energy efficiency than 99.99% of the general public. You may commence acting smug.

I call it the Rule of Twelve, and it states that if you know twelve concepts about a given topic you will look like an expert to people who only know two or three. If you learn more than twelve concepts about a topic, the value of each additional one drops off considerably.

Allow me to be the first to confess that twelve is not a magic and inviolable number. It just sounds better than The Rule of Several, Give or Take Two or Three, With Lots of Exceptions. So don't get hung up on the number twelve.

The power of this rule is that seemingly impenetrable topics are less intimidating if you know there are only a dozen concepts to learn. And often the details of a subject are unimportant if you know the big concepts. Let me give you an example.

As I've mentioned, my wife and I are in the process of building a house. One of our goals was to make it as energy efficient as practical, while still having the features we wanted. And that meant learning the twelve-or-so concepts of green building that would get us where we wanted to go. Those concepts aren't neatly listed anywhere, so you have to flail around until you scare them up. For example, I spent a huge amount of time trying to figure out the best type of insulation for the walls. I looked at everything from SIPS to hippy ideas about hay and compressed dirt, to blown-in cellulose, to standard batting. And it seemed no one could give me a definitive answer on what R-value was best for a home in my area. Big developers used whatever was cheapest and met code, because they didn't have to pay the utility bills after their homes where sold. And every individual home builder and owner seemed to have his own theory on insulation type.

Eventually we talked to some engineers who explained some of the twelve concepts to us, and that made the decision easy. It turns out that in my climate, no matter how you insulate the walls, it's the windows and roof that will determine (mostly) how much heat penetrates your house. There was never a need to learn about exotic wall insulation methods. We just had to make sure we knew the twelve concepts about windows, roofs, thermal mass, orientation to the sun, chimney effect, and a few other concepts more important than wall insulation.

If someone is explaining a subject to you by listing lots of facts and examples, without explaining any of the twelve concepts, you probably aren't learning anything useful.

Suppose you hire a plumber to fix a leak. You pay him for his work and he leaves. A year later he calls back and asks if you would consider giving him additional money because you continue to get benefits from the repairs. In addition, he argues, you could help subsidize future customers that would otherwise not be able to pay for his services. Would that seem appropriate?

Now imagine he calls back every few months for the rest of your life, asking the same frickin' question every time. Would you be okay with that practice?

Private colleges do this sort of thing all the time and somehow it seems okay. It makes me wonder what-the-hell kind of brainwashing goes on in those institutions.

I have an internal conflict when my alma mater, Hartwick College, asks for money. On one hand I feel a strong, irrational impulse to give, just as they somehow programmed me to feel. On the other hand, my degree was in economics, so the rationally trained part of my brain says paying twice for a service that was rendered once is irrational. But I'm glad the school pumped out lots of psychology, nursing, and sociology majors to donate money and keep the college afloat. I'd hate to have an economics degree from a college that went out of business.

A lot of what passes as art is really an understanding of rules. Here I am using "art" loosely to mean anything from fashion to design to painting a picture. The more rules you know, the better you are as an artist.

Let me give you an example from design. Say you want to design a magazine cover about a hot new type of consumer gadget. One idea for the cover involves a picture of the gadget and nothing more. The other idea involves a picture of a person who happens to be using the gadget. Which one do you pick?

Answer: The person using the gadget.

One of the rules of magazine covers is that you want to include humans whenever possible. Humans are wired to be more interested in other humans than anything else.

My wife and I are in the process of building a home and choosing all the details that will be in it. One of the choices involves doors. If you start the process by imagining all the possible doors in the universe, the task is overwhelming. But eventually you can figure out the rules, and that narrows your decisions. For example, you want most of your doors to look the same, or at least be in the same general vein. That's a rule. And the closer any two doors are, the more similar you want them to be. That's a rule. And once you have made a decision on the general style of the home, the door choices narrow by about 90%.

In the course of my Dilbert career I've posed for literally hundreds of photo shoots. I like to observe the photographers and figure out their rules. I know they always want the lamp removed from my desk. I know they want my computer "cheated" in a way that is unnatural for the user but looks good in pictures. I know the window behind my desk is going to be a lighting problem. And I know which six-or-so positions they are going to ask me to pose in.

This all makes me wonder how far computers will advance in creating art and design. My guess is "farther than you think." The limit will be our human ability to realize when we are using rules versus something squishy like judgment or having a "good eye" for something. Once the rules are understood and programmed into computers, they should exceed our skills at everything from architecture to fashion design.

Suppose you created a Ponzi scheme that worked like this: For every dollar someone thought they were investing in your scam, you simply kept ten cents and put the rest in the bank, not invested in any way.

Every month you would generate a fake statement showing that your victims earned some healthy return, say 15%. You wouldn't need to worry about people withdrawing money because your fund would allegedly be the best around, at least according to your fake statements. And you'd still have 90 percent of the money sitting in the bank in case someone really needed some back.

This scheme would be highly illegal of course. It would also be one of the best investments anyone could have made over the past ten years, assuming few people withdrew any money. Most legitimate investment funds lost more than this hypothatical fund.

Almost everything I ever learned about investing turns out to be wrong. I learned that buying and holding a diversified portfolio of stocks was a sure winning strategy in the long run. So far, my lifetime stock investments are negative.

I learned that the safest investment is real estate, especially in California, because "they aren't making any more land." That theory hasn't worked out too well.

I learned that investing in California municipal bonds was extra safe because they were insured. That's great until the insurance companies themselves become insolvent.

So if everything that was good is now bad, is there any investment that we all assumed to be bad that is now good? (Other than stuffing cash under the mattress. Too obvious.)

Whenever I see tragedy I immediately look for the economic opportunity it creates. So when I saw this news story about a guy who shot a woman because he thought she was a monkey, I wondered how the woman, who insists she is not a monkey, can cash in when she recovers.

http://www.msnbc.msn.com/id/29685956/?GT1=43001

My suggestion is that she should approach the people who make Nair and ask to be their spokesperson. The commercial could go something like this:

Spokesperson: "Are you tired of being shot because your neighbor thinks you're a monkey? Me too. That's why I use Nair. And now I buy my fruit from the grocery store. That probably helps too."

I'm going to closely follow this case. If the shooter gets acquitted I plan to use the monkey defense if I ever get arrested for a similar crime. Obviously I would only need that defense if I shoot an unarmed citizen, but frankly the only thing stopping me now is the lack of a good alibi. This monkey thing could be just the ticket.

One problem with using the monkey alibi in a California suburb is that we don't have enough actual monkeys to make the story seem plausible. So in phase one of this plan I will need to breed monkeys in my garage and release them until some sort of critical monkey mass has been achieved. Then I'll never have to listen to someone talk on a cell phone during a movie again. I'll tell the arresting officers "I thought it was a monkey."

But with my luck there is probably some sort of law against shooting monkeys in crowded movie theaters anyway, no matter how much they deserve it. I should probably do more research.

The other day I was in a restaurant and saw a sign advertising "Sliders Fridays." From what I gathered, they offered a deep discount on tiny hamburgers, called sliders, on Friday nights. The interesting thing about this discovery is that I own the restaurant and it's the first I knew of it. (Stacey's at Waterford: www.eatatstaceys.com)

I don't just own the restaurant. I also manage it, although I use that term loosely. I've taken the concept of hands-off management to the next level. Most of the time I have no idea what the staff is up to. They organize customer events, execute marketing ideas, hire and fire, change the menu, and pretty much anything else they want. I only get involved if there is a largish expense that needs to be approved. I see the financials daily, by e-mail, but I'm mostly about the bottom line.

As a well-known critic of managers, I painted a big red bulls eye on my back when I started managing the restaurant. For the first year I was involved in the details somewhat, but primarily to establish an operating culture. I wanted to give them lots of flexibility to try new things, and even more freedom to fail. And I wanted them to feel like it was their own business.

I'm lucky because I have exceptional managers, with lots of experience, who appreciate the freedom they are getting. I think freedom partly compensates for the fact that restaurant pay isn't the best. It's a luxury not having your boss breathing down your neck. Apparently something is working because the restaurant quality is better than it has ever been, and January revenues were slightly up from last year despite the tanking economy. I'd love to take credit for that, but lately all I do is eat there.

The principles I tried to establish with the staff early on, that seemed to have stuck, include these:

1. Have fun. Loosen up.
2. Try something new. Often. Keep whatever works.
3. No penalty for a new idea failing. Trying is the thing.
4. Employees are more important than customers.
5. Stop asking Scott for approval. Just do it.
6. Managers get to see the financials.
7. Being a jerk to coworkers is grounds for termination.
8. Do whatever seems smart and fair to make customers happy.
9. Watch the competition closely and borrow their best ideas.

It probably helps that the staff realizes that getting another job these days is a dicey proposition, and they all want to make sure the restaurant stays in business. When someone doesn't pull their weight, the staff weeds them out on their own, either directly or indirectly.

It's a fascinating exercise. Obviously it only works if you have the right people in key positions. But so far, so good.

During the Great Depression the unemployment rate hit 25%. We're flirting with 9% in California. But can you compare unemployment rates across the decades?

Obviously the unemployment rate doesn't include anyone who stopped looking for work, so it tends to understate things. That distortion is often discussed. But there's also a problem in comparing the rate across decades. There has been a huge surge in the number of small businesses over the past fifty years. Many are the "buy yourself a job" type, meaning your income during good years will be about the same as if you had a normal job and salary. But what happens if the economy sours and all of those people who appear to be working at their small businesses are actually using their savings to stay afloat? Can you really call those people employed?

I would argue that any self-employed person, and any small business owner who is losing money, or using savings to stay afloat, is functionally unemployed, or at least underemployed. I wonder what the unemployment rate would be if you included those people, so you had a better apples-to-apples comparison with the Great Depression.