Googlemaster on learning from disaster vs success

People don't usually analyze the reasons for success, but they do analyze the reasons for failure. The company I work for has a thing we do called "root cause analysis" and "the five whys" where we dig and dig and dig to try to find the real reason for failure. We don't usually do this for successes. Maybe we should.

- The customer reported a primary key violation on table FOO.
- Why is the customer getting a PK violation on FOO? Because the software is trying to insert two records for the same thing.
- Why is the software trying to insert duplicate records? Because two threads are trying to do the same work.
- Why are two threads trying to do the same work? Because there's a bug that wasn't caught.
- Why wasn't the bug caught before release? Because we didn't test the multi-thread scenario.
- Why didn't we test the multi-thread scenario? We were going to test it, but we ran out of time. (Or, you could branch off in a different direction here and go with "Because we didn't know the software needed to support multiple threads of execution.")
- Why did we run out of time? Because "just a small feature request" was added to the schedule after we did the planning and estimation.
- And so on...

Engineering Project Lifecycle

1) Enthusiasm
2) Disillusionment
3) Panic
4) Search for the Guilty
5) Punishing the Innocent
6) Rewarding those not involved

(thanks to Mark Roulo)

college grads & jobs

at the Wall Street Journal

One small answer to the engineering gap?

Johnny Chung Lee made the NYT today .
My favorite part of the article, on building an interactive whiteboard with a wii remote:

An after-school Lego robotics club for fifth graders at Clara Byrd Baker Elementary School in Williamsburg, Va., built a Wiimote whiteboard in four one-hour sessions. “Once it was done, the kids were so excited,” recalls Kofi Merritt, then the school’s computer resource specialist, who suggested and advised the project. “They recognized themselves as innovators and demonstrated the whiteboard in classroom after classroom.”

Lee provides specs and instructions for all his inventions free online. What a great way to introduce students to engineering as the U.S. engineer gap is growing.

According to Sheila Riley of the EE Times:

The population of experienced engineers is aging, he (Albert Helfrick, chair of electrical and systems engineering at Embry-Riddle Aeronautical University said. "There's a serious problem in our country with people like me: gray-haired people who could retire tomorrow," he said. If large numbers do retire, the U.S. faces a severe engineering shortfall.

Joe Sciabica, executive director of the Air Force Research Laboratory, agrees:

"We are facing a crisis in this nation," Mr. Sciabica said, referring to a loss of technical talent and experience as an aging workforce of scientists, engineers and mathematicians prepares for retirement.

"What alarms me more is that the professors to teach the next generation are also retiring," he added.

Looks like loss of quality teaching isn't just an ed school issue.

Mark Roulo & Steve H on open vs closed loops

An open loop control system is one in which you don't bother checking to see how you are doing. An example would be a robot arm, where to move to a certain position, one just moves a motor a certain number of revolutions, but doesn't check to see if maybe the gears are slipping.

Open loop systems tend to be simpler and cheaper than closed loop systems, but less reliable.

A closed loop system would be the robot arm with a sensor that fed back the arm position. In this case, even with slightly slipping gears you can get the arm to the correct location because the robot might issue one extra revolution command to make up for the slipping gears.

Poor schools and classrooms tend to run open-loop ... no one knows if the kids are learning what they are supposed to learn. Well run schools and classrooms run closed-loop by checking the kids for progress AND THEN TAKING ACTION (e.g. reteaching). Even better would be a school or classroom that was closed loop on the teaching itself. For example, if kids kept not learning, trying to figure out what to change so that the kids learned the first time around.

I don't get the impression that the second version is done formally in very many schools (or businesses for that matter).

Positive feedback means you do more as you get closer to what you want. I don't think any engineers design these things on purpose, but sometimes you get one anyway (I think ram-jets have a built in positive feedback ... without external controls, the faster they go the faster they want to go until they burn themselves up).

Mark Roulo

Steve H:

"I don't get the impression that the second version is done formally in very many schools.."

Because of NCLB, our state mandates that this process takes place. They send out (almost worthless) questionnaires to parents and students and they hold parent-teacher meetings to review the standardized test results.

For example, the committee might see that the standardized test scores for problem solving in math have gone down a few points. They will sit around and discuss the problem. It's down only a slight bit, so there is not much of a problem, right? Perhaps it's due to the small sample size (they get to sound rigorous). Well, in any case, the administration will tell the teachers in their next meeting to emphasize problem solving more. OK, next problem.

The flaw, as you can see, is that this is all relative. You can provide all of the feedback you want, but if the basic structure of the system is wrong, it will never be fixed. Standardized tests will never tell you that many more kids should be getting to algebra in 8th grade. In fact, it tells the school and many parents the opposite. (They conveniently ignore international tests.)

This reminds me of my son's Science Olympiad project. He can tweak things all he wants, but his basic vehicle design will never reach the required maximum distance.

In our district, "Extra Help" is the answer to all learning difficulties, across the board. Students are supposed to "be proactive and seek extra help." If a student does not seek Extra Help then he deserves his C or D or F. At the high school, students are to seek extra help and also practice "self-advocacy," which means parents are not to contact the teacher or the administration about a problem until the student has tried and failed to solve the problem on his or her own.

This philosophy has now been imported into the 4-5 school. When parents raise an issue with a teacher, the parent is told that the student should have come to the teacher with the problem. It appears that ten year olds are supposed to monitor their learning, seek Extra Help, and self-advocate.

Dale on Schaum's outlines

I've been a long-time reader and very very occasional poster on KTM. In the last month, I decided to go back to graduate school in engineering, 18 years after graduating from law school and 22 years after my last math or science class.

The head of the math department at the university I'll be attending suggested that I start my prep work with Schaum's College Algebra. So, I can tell you that these books are well regarded, at least in some circles.

Great to know.

I'm hoping Dale will keep us posted on his studies in grad school (in his spare time, of course).