Philip Greenspun’s Weblog

Our helicopter flight school sold coupons for 2600 introductory lessons and I’ve been trying to train the other instructors to teach a group ground school (outline). When I teach a group of 15 or 20 students, I do it by going around the room, learning each person’s name, and asking a question. If the person doesn’t give the right answer, I ask the next person. If that doesn’t work, I give a hint and ask the next person. We keep going around the room with questions such as “What happens if you have the helicopter parked on a frozen lake and turn on the engine to start the rotor system spinning?” (answer: fuselage turns in the opposite direction; this leads naturally to the next question “What would you then want to add to the helicopter?” (answer: tail rotor)).

Students stay awake because they know that they’re going to be asked a question within the next five minutes or so. The material ends up being naturally paced to the comprehension level of the class. If people aren’t answering correctly, the class slows down, people have more time to think, and I provide more explanations. At any time during the two-hour class I can tell you which students are getting it and which may need remedial instruction.

Helicopter instructors who’ve watched me teach the class assure me that they’re ready to do it themselves. I sit in the back to make sure. They stand up in the front of the room and start talking. They might ask two questions per hour of the students and they typically won’t select a student to answer, but rather let the student who is best-prepared answer. After about 20 minutes, just as education researchers have found, most of the students assumed a glazed uncomprehending look. Functionally I think it would be better to call this “live video” rather than teaching, since the same effect could be achieved by emailing students a link to a video to be viewed in a Web browser.

These are guys with 20 or more years of experience teaching helicopter students, both on the ground and in the air. They are genuinely great teachers 1 on 1. Yet they are hopeless in a group instruction setting (this was not only my (biased) conclusion, but that of our young assistants). It turns into high school all over again, with about 10 percent of students learning a lot, 40 percent muddling through, and 50 percent enduring a total waste of their time (since they quickly got lost and then the rest of the lecture was over their heads).

I’m basically giving up on the group idea because I don’t think it is possible for the teachers that we have to be effective in front of a group and we can’t accept the kind of failure-to-learn rates that are common in our public schools (the laggard graduates of our lavishly funded public schools have wrecked the U.S. economy but they haven’t wrecked any helicopters, which is a risk that is ever-present at a flight school if a student lacks proper ground schooling).

People talk about the importance of teacher training for our public school teachers, but as far as I can tell there is no way to make the lecture method work for anything that requires students to develop a conceptual grasp of a topic.

[You might ask what we’re going to do with our 2600 students. The answer is that I’ll continue to teach them in a 20-person Q&A session and the other instructors might teach them in groups of 2.]

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I attended a social gathering this afternoon with a lot of folks whose children had recently graduated from college. The kids had gone to lavishly funded Massachusetts public schools or expensive private schools, soaking up at least $200,000 in funds for their first 12 years of education. Then they’d spent at least $300,000 in parental money and opportunity cost (not working) for four years of college. Each child, therefore, represented at least $500,000 of investment. What was the return on that investment? Nearly all of the kids were unemployed and living at home with their parents.

Consider the alternatives. The $500,000 could have been invested in Pizza Hut franchises in China, mobile phone towers in India, or supermarkets in Brazil. With a 10 percent return on investment, not atypical in these high-growth countries, the money spent to educate an American child could be yielding $50,000 per year in income. http://en.wikipedia.org/wiki/Personal_income_in_the_United_States shows that this is about the same as the average American with a master’s degree earns. Of course, our uneducated children would still be able to perform some paying work, so their total annual income would be well in excess of $50,000.

Just as we’ve produced a health care system so expensive that we’d be better off without doctors and hospitals, we’ve managed to create an education system so expensive and ineffective that we’d be better off not sending anyone to school.

[Note: We would not have to have invested in foreign countries to come out ahead; http://www.moneychimp.com/features/market_cagr.htm shows that had we put money into the S&P 500 starting 16 years ago we would have realized a 7.8 percent annual return on investment.]

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A friend pointed me to Thomas Friedman’s column advising new college graduates to start companies and/or work for startup companies. He goes to advocate that the Politburo, Gosplan, and Premier Obama allocate more resources to startup companies in their next Five Year Plan.

This seems like terrible advice to give a young person who is heavily laden with student loan debt. A person with big debts that cannot be discharged in bankruptcy is not a person who should be taking risks. Given that government jobs pay twice as much, on average, as private sector jobs (source), and carry a much lower risk, and are more available (graph), wouldn’t a kind-hearted older person advise a fresh college graduate to work for the government?

Stats:

• Bureau of Labor Statistics says that the Washington, D.C. metro area led the nation in job growth (June 2, 2010 release).
• Federal workers love their jobs, with only 0.1 percent quitting per month compared to 1.7 percent in the private sector (table)

[Friedman does not seem to be advising young people based on his personal experience. Friedman is an employee of the New York Times Company, a 160-year-old enterprise with more than 10,000 employees. Friedman achieved an additional level of financial security by marrying the heiress to a multi-billion dollar real estate development fortune. Wikipedia does not show that Friedman ever worked for a small company.]

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I pulled Normal Accidents: Living with High-Risk Technologies out of the library this week to see what a book written in 1984 might have to say about the Deepwater Horizon explosion in the Gulf of Mexico. Charles Perrow, then and now a professor of sociology at Yale, chronicled accidents over the decades in different industries. Earlier technologies mostly involved a linear production sequence. If a machine failed, a process was interrupted until the machine was fixed and the consequences of that failure were obvious and limited. Perrow’s conclusion was humans are bad at analyzing systems with complex interactions, e.g., where one component serves multiple functions and if it fails there are multiple consequences. He kicks off the book with a discussion of the Three Mile Island nuclear power plant meltdown.

Perrow says that failures in complex systems are invariably blamed on human error: “lack of attention to safety features; lack of operating experience; inadequately trained personnel; failure to use the most advanced technology”. People don’t look at the characteristics of the systems themselves and ask “Could the potential for accidents have been reduced by eliminating complex interactions?”

Perrow does not use offshore oil drilling as an example, but he has a chapter on petrochemical plants. The plants are “tightly coupled and [have] many complexly interactive components. … it illustrates the presence of system accidents in a mature, well-run industry that has a substantial economic incentive to prevent accidents.”

In Perrow’s chapter on aviation, the emphasis is on the autopilot: “workload has become more ‘bunched’, with long periods of inactivity and short bursts of intense activity. Both of these are error-inducing modes of operation.”

Perrow suggests that the nuclear power industry be shut down because it can never be made sufficiently safe. A nuclear power plant is simple proven technology compared to what BP and Transocean were up to with Deepwater Horizon.

Computers have gotten cheaper and faster since 1984, but it is unclear that humans have learned anything. If we are intent on intensifying our usage of the Earth, both by increasing the population and having the average human consume more resources, Perrow would tell us that we will have to foresee periodic unforeseeable human-caused disasters.

[Perrow noted, back in the early 1980s, that “One enormous risk which the industrialized nations may be facing is not considered in this book on normal accidents… This is the problem of carbon dioxide produced from deforestation primarily, but also from burning fossil fuels such as coal, oil, and wood. This threatens to create a greenhouse effect, warming the temperature of the planet, melting the ice caps, and probably causing an incredible number of other changes, most of them disastrous.”]

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I tried to convince an American economist to take a few hours off last weekend and do something fun. “I have to work,” she said. I then asked her if Russians or Americans were smarter. “Russians are certainly better educated,” she allowed (in our helicopter ground school, a Russian high school course in physics taken 35 years ago turns out to be more useful than a recent U.S. college degree in science or engineering (posting on the subject)). Did the latest employment report show that nearly all new jobs in the U.S. were on the government payroll? She agreed that it did. So didn’t Russian economists in the Soviet era thoroughly analyze a centrally planned economy in which nearly all new jobs were created by the government? Why would she add her feeble efforts to the Herculean achievements of the Russians 1950-1980?

I wonder if this explains why so many recent college graduates with Econ degrees are unemployed.

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California taxpayers reading this Weblog will appreciate the following links from a reader…

The first is an article about a disabled California Highway Patrol retiree who collects over $100,000 per year as a disability pension and “was hired by the federal government to be security director at San Francisco International Airport” (2007 followup).

The second is a Sacramento Bee tool for searching state employee salaries. Pick an agency and then click “search” and the top-paid workers are displayed. Selecting “California Highway Patrol”, for example, brings up a sergeant earning $304,477 per year. When you reflect that the average worker’s pension is approximately the same cost as his or her salary (using realistic assumptions about investment returns and the likely life expectancy of someone who comfortably retires to the golf course at age 50), this is an entire page of state workers who are being given more than $500,000 per year in total compensation. The pension system itself is apparently hugely expensive to run, with plenty of workers there earning over $300,000 per year. Fish and Game are cheaper, with only 4.5 pages of people being paid more than $95,000 per year (plus pension obligations of at least another $95,000, for a total of $190,000/year if compared to a private industry salary).

The federal government’s unbridled spending isn’t too surprising because the feds have printing presses for creating additional dollars. States that pay policemen $600,000 per year (including pension commitments) strike me as odd. Where did they think the money would come from?

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Friends have asked what I thought of Helen Thomas and her plan (video) to dispose of the unwanted Jews in Israel by sending them “home” to Poland, Germany, and America (three countries she specifically mentioned). I surveyed a few articles on the subject and did some searching within Google News and found no evidence that any professional journalist identified the main flaw with Helen Thomas’s statement: the Jews of Israel did not come from Poland, Germany, or America. As the Europeans were very successful in their efforts to kill their Jewish neighbors, very few survived to emigrate to Israel. The largest demographic group within Israel is Jews whose parents came from Muslim countries, such as Egypt, Morocco, Iran, Iraq, Syria, etc. It seems unlikely that these countries would want to welcome back the children of Jews that they kicked out decades ago.

Is it too much to ask professional journalists to check Wikipedia before writing a story?

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A friend sent me “Higher education’s bubble is about to burst”, an article loosely related to my year-old “Universities and Economic Growth”.

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It is with a bit of shame that I recall a lack of reflection on Memorial Day regarding the American soldiers who put their lives at risk every day in Iraq and Afghanistan. This story from a Boston University professor who lost a son in Iraq brought me back to reality. Even if we have no idea why we are engaged in all of these overseas wars, we should remember our fellow citizens who paid with their lives.

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Folks:

After four years of daily use, my 2006 Dell XPS 400 has finally become obsolete. It has been running 32-bit Windows XP and I want to use Adobe Premiere Pro with my new Sony camcorder. The hardware engineers who built what turned out to be a flawless Dell were no match for the world’s software engineers, who have created video editing software that will run only on 64-bit operating systems.

Here are my requirements:

• drive old Dell 30″ display (2560×1600 pixels through single DVI cable)
• be nearly silent
• be no taller or deeper than 18″ (the biggest current Dells are 19.4″ high)
• run Adobe Photoshop and Premiere Pro
• be fast at converting RAW photos to JPEG (I must admit that my old computer seems a bit pokey when dealing with HD video or the latest 20+MB camera RAW files)
• be responsive for video editing and reasonably fast for format conversion (the Sony captures in AVCHD, which cannot be used anywhere)
• run Windows 7/latest Microsoft Internet Explorer so that I can use FAA Web sites to sign off students
• run cygwin and PuTTY so that I can connect to and maintain some Linux-based servers
• run OpenVPN
• run software included with various peripherals, including Fujitsu ScanSnap scanner and a couple of printers
• hold a fair amount of data (1.5 TB hard drive? Possibly with a mirror so that a drive failure does not inconvenience me, though actually I cannot remember the last time that I had a home computer drive failure)
• burn a Blu-Ray disk for distribution of HD video

Due to all of the software that has been freighted onto this machine over the years, some of which requires license keys that I have surely forgotten, moving to a new computer is going to be painful and time-consuming. So I’d rather not do it too often and would be willing to spend some extra money now to delay the next replacement.

My actual current needs could probably be handled reasonably well by a $750 desktop PC, but in light of the labor involved in configuring the new computer as my daily desktop I am thinking of treating myself to a monster fast machine. I think that I could spend $2000 without feeling embarrassed.

The latest and greatest Intel Core i7 processor is available only on Dell’s XPS 9000, a machine that is physically too large, and the option costs $1000 extra. A 6-core AMD seems to be available. And then there are the Dell “workstations” with Xeon CPUs. I can’t figure out any of the differences among these CPUs. Is it too much to ask Intel to label their desktop CPUs “slow, medium, fast, super” instead of “Core i7-975 Bloomfield” (the complete list is daunting and it is just for one variant of “Intel Core”; Dell also sells “Core i3” and “Core i5”)? Or how about just give them numbers that correspond to performance benchmarks? That way I could know how much faster a new machine should accomplish a task such as video encoding.

My inclination is to stick with Dell, but I would be open to other brands as long as the acoustic engineering is good.

Ideas? Suggestions? What CPU? How much RAM?

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