Turtles all the way down

I usually don’t mind winter.

But this year it has been cold, snowy and miserable for better than two and a half months. Just when you think it is over, it comes back. At this time last year, I was getting out my deck furniture. This year, we’ve got several inches of old snow, one inch of new snow that arrived last night, and single-digit temperatures teed up for next week.

Commuting is ugly and uncomfortable, and all is dreary.

Everybody is complaining about the weather. Now, I have officially joined them.

A long article from Chris Anderson on the economics of free. Once again, I can’t get this topic out of my head, but I also can’t seem to fully get what it all is going to mean. But I’m a huge believer in free because I’ve been watching it happen for years.

Enabled by the miracle of abundance, digital economics has turned traditional economics upside down. Read your college textbook and it’s likely to define economics as “the social science of choice under scarcity.” The entire field is built on studying trade-offs and how they’re made. Milton Friedman himself reminded us time and time again that “there’s no such thing as a free lunch.

“But Friedman was wrong in two ways. First, a free lunch doesn’t necessarily mean the food is being given away or that you’ll pay for it later — it could just mean someone else is picking up the tab. Second, in the digital realm, as we’ve seen, the main feedstocks of the information economy — storage, processing power, and bandwidth — are getting cheaper by the day. Two of the main scarcity functions of traditional economics — the marginal costs of manufacturing and distribution — are rushing headlong to zip. It’s as if the restaurant suddenly didn’t have to pay any food or labor costs for that lunch.

In the 1960’s, Paul Diederich and others conducted a study of how essays are graded. They managed to talk over 50 people, including teachers as well as professionals, into being graders. The essays were the product of high school students. Each grader had to anonymously grade a large number of essays, and categorize each on a scale of 1 (worst) to 9 (best).

Surprisingly (or perhaps not so surprisingly for those who have graded essays), every single essay received a wide range of disparate grades. One over third of the essays received every grade, from 1 to 9. All of the essays received at least five different grades.

But how could this be?

Diederich and team analyzed the results and found that each grader applied their own criteria when grading. While the experiment did not have graders try to explain their criteria, Diederich was able to find that most graders fell into one of five criteria categories. For example, some graders based grades largely on their perception of the quality of the essay writer’s ideas. Others based their grades on the writer’s mechanics, such as spelling and grammar. Some were mostly focused on organization. Other graders used even different criteria.

But what does it mean?

This is the hard question. Apparently, a student’s essay grades can vary widely based on who is doing the grading. This might be mitigated if the graders agree ahead of time on a “cut sheet” that assigns a number of points to various aspects of the essay. Either the cut sheet or a representation of it could be provided to the students so that they have a better idea how they will be graded and the weights the grader will assign to each criterion. Additionally, if the students and the grader work together for some time, the students will learn the grader’s “style” and adapt to it.

Perhaps this is the most important point. If the students are given enough examples of what the grader’s criteria are, their ability to adapt to that criteria will increase dramatically. If they are given fewer or no examples, the students will be more likely to view their grades as an arbitrary crap-shoot.

Source: Paul B. Diederich, Measuring Growth in English, National Council of Teachers of English, 1974 (this is the source of the facts, not my opinions).

Resist the urge to assign too much reading. Resist it!

I know you mean well. Those 17 cases you want us to read for each class are all interesting and precedential. But if you’re going to only discuss 2 of them, and that is what you do each class…here comes the unintended consequence…students will read NO cases.

Sure, we’ll read a commercial outline, scan summaries and headnotes so that we have a clue about the cases, but we won’t invest time where there is little payoff.

Reading assignments need to be “just right.”

On the bright side, I now feel justified not hauling that 1500 page casebook to class.

Some quotes from luminaries at the Mobile World Congress:

“Twenty-five years ago Microsoft was a puppy,” explained Softbank CEO Masayoshi Son. “And everyone said ‘ah, you are cute!’ But then they became huge in the PC space, and the guys that made the computers, and built the infrastructure didn’t make much money. If the mobile industry is not careful the same thing will happen, and carriers will become dumb pipes,” he said.

“In the end, technology is not what matters: it’s services, it’s applications, it’s experiences,” Vodafone CEO Arun Sarin said during his keynote Tuesday. Carriers must offer subscribers a variety of ways to communicate–like SMS, email or social networking sites–the carrier must “be in all these places.” He added: “We must not allow ourselves to become bit pipes and let somebody else do the services work.”

With all due respect to Son-san and Mr. Sarin, as an end user, a dumb pipe is exactly what I want.

I don’t want services bundled with my access technology. I want to choose my own services.

I don’t want my access to be limited or filtered, or content being given priority over other content. I want all content to be served equally.

I don’t want my service provider to redirect failed DNS queries or to hijack my web session when a page can’t be found.

I don’t want my service provider inserting ads into my browsing session.

I want a simple bit pipe to use as I’d like. Nothing more, nothing less. Of course, you may offer me services, such as telephony and video over the bit pipe you provide and if they are good services I may choose to buy them. But don’t force me to do so. I prefer to spread my risk around.

Make your service sticky by making it un-sticky. Make it easy for me to do what I want with it. Don’t nag or remind me of your presence. Do all that and charge a reasonable rate and I’ll be a subscriber forever.

Benjamin Cardozo was a famous judge in the early part of last century, first in the highest court in New York and then in the Supreme Court. He wrote several landmark decisions, including Palsgraf v. Long Island Rail Road Co. and Jacob & Youngs v. Kent.

He is also infamous for writing obtuse, wordy opinions that are living hell to make sense of.

My Cardozo theory is that he was an above average judge with a strong sense of justice and fairness. However is was not the genius that many claim he was. Legal scholars (and law students) have hyper-analyzed Cardozo opinions, looking for meaning. Since these opinions are virtually indecipherable, meaning can easily be found…maybe not Cardozo’s meaning but the reader’s meaning that they project on Cardozo.

Not unlike some poetry, the further the writing is from plain language, the more likely that some will attribute more meaning to it than is really there. Analyses find way too much in Cardozo and give him credit for ideas beyond his text.

We’re taught in legal writing classes to NOT write in this style. The next day we spend two hours picking apart a Cardozo opinion.

The family is good and for that I’m grateful.

The workload in the office is reasonable and more than enough to keep me busy. I’m juggling between drafting patent applications, office action responses, infringement analysis, and some research and opinion work. I take the patent bar toward the end of next month which has me trepidatious since I’ll need to wrap up a few projects quickly then go heads down to study.

This semester at school is cooking along. The lecture courses (property and contracts) are somewhat more interesting than last year. Although the legal writing course is only 2 credit hours on paper, in reality it’s more like 4-5. My trial brief was completed last week, and now I have a ton of research to do for my appellate brief and oral argument.

I haven’t been getting as much exercise as I’d like, but my back is feeling better, though still sore. The weather here has been brutal, both cold and snowy. I’m hoping that will all be done with in a couple of weeks. Winter is beyond old at this point.

This is a post I wrote a little over 18 months ago, before I had the blog. It is a slice-of-life from a neighborhood event. Enjoy.

Yesterday was our annual neighborhood picnic. I found this out about 2 weeks ago though I’m sure that my wife had mentioned it at least once before. Maybe twice. She’s also an organizer for the event. My response to finding out was a shrug. I’m not as into these neighborhood events as I probably should be. Our neighbors are great but our older son’s food allergies make any event combining food and children extra stressful.

A few days before the picnic I find out that I’ve been drafted to watch the kids while my wife sets up, and that I’d be in charge of the kids during the whole event. Great, what little weekend spare time I get has been taken away. Oh well, at least its for what should be a fun event.

I grabbed the kids in the morning and took them to the gym. I had a pretty good workout, running 9 minute miles and working the abs. The boys played both inside and out in the child center since the weather was nice. Afterwards, we stopped by Starbucks for milk and bananas as a treat for the boys who had cleaned the playroom that morning. All was good, even with my younger son in the middle of potty training at the time and having to take him for bathroom breaks every 45 minutes.

In the afternoon, my wife goes out to grab some food and a few other things she needed and takes our younger son. The older one and I play video games. They return and she drops off the little guy, who is sound asleep, and she heads over to set up the picnic. She’s upset about things not going to plan - apparently the guy dropping off the jumper and inflatable slide arrived an hour early.

Around 4pm, she’s back, the situation is under control and our sleeper had just woken up from his nap. We load the kids and the rest of the supplies and drive over to the park, which is about a mile from our house. As one of the first groups there, we start setting up the grill and food tent while the boys play on the jumper and slide. In the past one of us would always watch them nonstop when out in public due to allergies and age. But as we’re with people who are mostly aware of our food allergy situation and used to dealing with small children, we are able to relax a little and just watch them out of the corner of our eyes.

Between 4:30 and 5PM the party gets started with about 20 families showing up. I trade off helping run the event, eating and keeping the kids entertained. My older son and I manage to climb this large rock at the edge of the park, and he doesn’t want to come down when I leave, despite the fact that he can’t get down on his own. The little guy wants to climb up as well but I tell him he has to wait until he’s five.

During our three-year-old’s frequent bathroom breaks, he chatters about jumping on the stepping stones on the walk to the bathroom. Heading back to the park, he talks about them some more. Once we get back, he says, “Daddy, gotta go potty again!” Rolling my eyes, I take him to the bathroom again and once more the stones elicit his attentive chatter. In case you hadn’t noticed, he rarely stops talking when he’s excited about something. On the way back, again lots of discussion of the stones. Finally back at the park he says he has to go AGAIN. But after I ask him if he really just wants to walk on the stones, I find out that that is why he wants to go potty. So I promise him more stone-walking later and bribe him with popcorn to stay. In the mean time, our other boy gets heavily involved in games of cake-walk, water balloon toss, and sack races.

Did I mention how beautiful the weather was? 80 degrees, sunny and no clouds. Not a one. Well maybe just one…a big one. At about the time that we start noticing this dark cloud moving in, we hear thunder. Far off to the west it’s raining, but no one seems to mind. After all, the weather report said that today would be a great day and getting a little wet is not such a big deal right? But then the lightning starts. No rain on us yet, but we decided to pack it in. Our older son is afraid of the lightning and starts whining, which leads to crying. I’m trying to pack up as much stuff as I can as fast as I can while getting the kids to carry something. He sort of gets a grip on himself and we head to the van. I get the boys settled in their seats as it starts to pour. My wife and I go back to get more stuff from the field. We get soaked to the skin while the wind starts blowing and the lightning is striking all around us. Most of our neighbors scatter but a few brave ones stick around to help out. We’re very thankful for them.

Finally, the van is packed with piles of wet junk, we leave our grill and table at a neighbor’s house, and we head home. My wife unloads the car while I marshall the boys inside…to discover that we left the windows open. Slight change of plan…the boys are dirty and muddy from being out in the rain so I instruct them to remain in the kitchen and I run around the house closing windows, wiping sills and drying the floors. Once I get that situation under control, I herd them upstairs for a quick bath as the thunderstorm dies down. My wife goes back to the park to get the rest of the stuff and gets back looking like she had jumped into a swimming pool with her clothes on. But the worst is over. The boys are in their pajamas, the house is relatively clean sans the drenched picnic stuff now sitting in our garage. So we call it a night.

Usually these neighborhood events are fun. But after getting caught in a violent thunderstorm at this one, I can only hope the next event is really boring.

The first person says a small number, preferably less than ten. Each subsequent player has to say a higher number, with play cycling and repeating through all of the players. The winner is the one who says “Infinity!”

My four-year old made this game up, after discovering that infinity is the “last number.”

He usually wins.

For eight years, I taught part-time in the Electrical Engineering graduate program at Northwestern University. The MSIT program is for a professional degree, and focuses developing students’ technical and business skills. It is very selective, the students are quite good, and it was a pleasure for me to be part of it for so long.

Thinking about grades a lot lately, I’ve been data-mining eight years of raw scores to determine if there is anything to learn from them. I’m not sure that I’ll discover any new principle, but I’ll share the results as I go.

Each year my class consisted of anywhere from 20 to 33 students. Four out of the eight years I based the final grade on two exams, a midterm and a final, as well as four homeworks and class participation. The final grade was heavily based on the two exams. In 2000 I only gave two homeworks, in 2001 and 2002 I gave three homeworks, and in 2007 I assigned no graded homeworks.

Each year the class covered largely the same material. In latter years I moved faster and covered more topics in slightly less depth. Midterms and finals were similar year to year, often reusing the same questions, though most years I switched out at least 25% of each exam.

I gave model answers to all of the homeworks. I did not give model answers for the exam questions, but in latter years I did give “practice exams” that were fairly accurate views of real exams.

Most years, the exams consisted of 2-3 “mechanical” questions and 1-2 “essay” questions. Mechanical questions required solving a particular type of problem, such as IP subnetting and aggregation or determining the DNS servers involved in a query. Essay questions were open-ended, required some creativity and tended to make the student apply concepts and think “beyond the classroom” to analyze issues.

One of the first questions I had was how correlated was a student’s midterm exam grade to that student’s final exam grade? In other words, how accurate a predictor is a student’s performance on one exam of their performance on another exam? If the correlation is very high, then that would indicate that evaluating students with a single exam would be appropriate. If the correlation is low, that argues for using multiple exams to evaluate students.

Correlations per year are below:

• 2000: 0.18
• 2001: 0.77
• 2002: 0.81
• 2003: 0.32
• 2004: 0.61
• 2005: 0.65
• 2006: 0.62
• 2007: 0.72

Aside from 2000 and 2003, the correlations between midterm and final exam scores are quite high. This means that, for a significant number of students, looking at either the midterm or the final exam grade is a good predictor of how that student did on the other exam. However for a minority of students, midterm and final exam scores were quite skewed.

There could be any number of reasons for this discrepancy. The student had a bad day or didn’t get enough time to study. Or, they studied in general but missed a key topic on the exam. Or, they knew the material reasonably well, but wrote their answer poorly.

Of course there could be a degree of grader error as well, especially on the more subjective essay questions.

But what about 2000 and 2003? I may need to go back and look at the exams to see if I can shed any light on why the correlations are so low. 2000 was my first year teaching in the program and I remember giving a final that was much harder than the midterm. It is possible that the difficulty of the final threw off some of the students. But that doesn’t explain 2003. At this point I don’t have any hard facts as to why we see such small correlations in those years.

If there is anything to keep in mind as I continue this analysis is that it seems that it is more “fair” to given at least two major exams, as well as some other graded assignments. Putting all of my evaluation eggs in one basket would have changed the grades of a number of students.

For example, looking at 2002, the year with the highest correlation, if I had not given a midterm and based final letter grades just on the final exam, 15 of 30 students would have had a different final letter grade. However, the magnitude of this change would have been small - none would have changed more than half a letter grade (for example, a B to a B+ or a B+ to an A-).

This begs further analysis. Perhaps a job for tomorrow.