November 28, 2018 1:56 PM

If it matters enough to be careful, it matters enough to build a system.

In Quality and Effort, Seth Godin reminds us that being careful can take us only so far toward the quality we seek. Humans make mistakes, so we need processes and systems in place to help us avoid them. Near the end of the post, he writes:

In school, we harangue kids to be more careful, and spend approximately zero time teaching them to build better systems instead. We ignore checklists and processes because we've been taught that they're beneath us.

This paragraph isolates one of the great powers we can teach our students, but also a glaring weakness in how most of us actually teach. I've been a professor for many years now, and before that I was a student for many years. I've seen a lot of students succeed and a few not do as well as they or I had hoped. Students who are methodical, patient, and disciplined in how they read, study, and program are much more likely to be in the successful group.

Rules and discipline sometimes get a bad rap these days. Creativity and passion are our catchwords. But dull, boring systems are often the keys that unlock the doors to getting things done and moving on to learn and do cooler things.

Students occasionally ask me why I slavishly follow the processes I teach them, whether it's a system as big as test-first development and refactoring or a process as simple as the technique for creating NFAs and converting them to DFAs. I tell them that I don't always trust myself but that I do trust the system: it almost always leads me to a working solution. Sure, in this moment or that I might be fine going off script, but... Good habits generate positive returns, while freewheeling it too often lets an error sneak in. (When I go off script in class, they too often get to see just that!)

We do our students a great favor when when we help them learn systems that work. Following a design recipe or something like it may be boring, but students who learn to follow it develop stronger programming skills, enjoy the success of getting projects done successfully, and graduate on to more interesting problems. As the system becomes ingrained as habit, they usually begin to appreciate it as an enabler of their success.

I agree with Godin: If it matters enough to be careful, then it matters enough to build (or learn) a system.

Posted by Eugene Wallingford | Permalink | Categories: Software Development, Teaching and Learning

November 26, 2018 2:04 PM

Self-Help from Hamming

In yesterday's post, I mentioned re-reading Richard Hamming's 1986 talk, You and Your Research. Hamming himself found it useful to manage his own behavior in order to overcome his personal faults, in service of his goal to do great work. I have faults, too, and need occasional reminders to approach my work more intentionally.

I've been at low ebb recently with my own creative work, so there is plenty of low-hanging fruit to be picked after this read. In the short term, I plan to...

  • focus my reading and programming time on material that contributes to specific research and teaching problems I'm working on. In particular, as Hamming says, "you need to keep up more to find out what the problems are than ... to find the solutions" -- then get to work actually solving problems.

  • attend seminars in other departments regularly next semester, especially in our science departments. This action works in the opposite direction as the first bullet, as it broadens my vision beyond my own work. Its benefit is in providing a cross-fertilization of ideas and giving me more chances to converse with smart people outside my area who are solving interesting problems.

I'm also our department head, an administrative role that diverts much of my attention and energy from doing computer science. Hamming doesn't dismiss "management" outright, as so many scientists do. That's heartening, because organizations need good leaders to help create the conditions in which scientists do great work. He even explains why a capable scientist might reasonably choose to become a manager: "The day your vision, what you think needs to be done, is bigger than what you can do single-handedly, then you have to move toward management."

When I became head, I had some ideas about our department that I wanted to help implement from a leadership position. Do I still such ideas that I need to drive forward? If so, then I need to focus my administrative work on those goals. If not, then I need to think about next steps.

Posted by Eugene Wallingford | Permalink | Categories: General, Managing and Leading, Personal

November 25, 2018 10:50 AM

Seek Out Idea Amplifiers, Not Sound Absorbers

Richard Hamming -- he of Hamming codes, Hamming numbers, and Hamming distance -- wasn't a big fan of brainstorming. He preferred to talk about his ideas with another capable person, because the back-and-forth was more likely to help the idea reach "critical mass". But not every capable person is a good partner for such conversations:

There is also the idea I used to call 'sound absorbers'. When you get too many sound absorbers, you give out an idea and they merely say, "Yes, yes, yes." What you want to do is get that critical mass in action; "Yes, that reminds me of so and so," or, "Have you thought about that or this?" When you talk to other people, you want to get rid of those sound absorbers who are nice people but merely say, "Oh yes," and to find those who will stimulate you right back.

What a simple bit of advice: seek out idea amplifiers, not sound absorbers. Talk with people who help you expand and refine your ideas, by making connections to other work or by pushing you to consider implications or new angles. I think that talking to the right people can boost your work in another important way, too: they will feed your motivation, helping you to maintain the energy you need to stay excited and active.

This is one of the great benefits of blogs and Twitter, used well. We have so many more opportunities than ever before to converse with the right people. Unlike Hamming, I can't walk the halls of Bell Labs, or on any regular basis walk the halls of a big research university or one of the great computing companies. But I can read the blogs written by the researchers who work there, follow them on Twitter, and participate in amplifying conversations. Blogs and Twitter are great sources of both ideas and encouragement.

(The passage quoted above comes from the question-and-answer portion of Hamming's classic 1986 talk, You and Your Research. I re-read it this morning, as I occasionally do, because it's one of those papers that causes me to be more intentional in how I approach my work. Like Hamming, "I have a lot of faults", which means that there is considerable value to be found in judicious self-management. I need periodic booster shots.)

Posted by Eugene Wallingford | Permalink | Categories: Patterns, Teaching and Learning

November 23, 2018 8:26 AM

The Peter Principle of Software Growth

This morning I read Against Software Development, which considers two tragedies of software development and a moral exhortation. One of the tragedies:

Software grows until it exceeds our capacity to understand it.

This observation reminds me of the Peter Principle from business management, which points out that people in a business are promoted until to they reach a level at which they are incompetent. Success in the hierarchy ends when people find that their skills no longer match the needs of their job.

We see something similar in software. We write a program to solve a problem. At this point, we understand the program completely so, when we see an opportunity for a new feature, we extend it. We still understand the system, so we add a bit more complexity, either implementing a new subtask or elaborating an existing feature with more detail. This process keeps happening until... we don't understand the program any more. Or, more likely, we understand it at a macro level but no longer grok all of the interconnections and dependencies among components. The result is Peter-like: the program stops growing. The root cause is not the incompetence of developers, but a fear born out complexity.

Having a system under a comprehensive set of tests can help stave off this fear. With careful attention, some time, and energy, we can use refactoring can sometimes reverse the entropy that sets in over time. But often the practicalities of organizations leave us with a big piece of software that we don't really understand, a system that can't grow or be changed to fit the evolving context in which it operates.

Many companies then find themselves in an odd situation: ossifying the organization's processes and procedures in order to stay in conformance with a piece of software its developers no long understand. Software rigidity becomes organizational rigidity.

Stay vigilant! With good development practices, perhaps you can push the point of no understanding farther into the future. But be ready for the day. It will probably arrive, sooner or later.

Posted by Eugene Wallingford | Permalink | Categories: Software Development

November 19, 2018 3:35 PM

Why Don't More CS Professors Use the Results of CS Education Research?

Over the last few days, there has been an interesting Twitter thread on the challenges of getting CS instructors to adopt the results of CS education research. Actually, it started as a thread and grew into a tree... Here's a reasonable jumping-in spot if you'd like to explore.

I imagine that it's hard to get research results into the classroom in a lot of disciplines. Research can be abstract and is usually out of context for any given school. But even when research groups implement curricula and train teachers, it can be hard to spread practices that we know work well.

The answer educators give for not adopting research results often boils down to, "It's complicated." Schools are different; students are different; the end goals are different. Indeed, the original Twitter thread spawned a student diversity conversation that picked up when the energy of the original topic waned. This tweet is a nice anchor for that conversation:

Majors vs. non-majors. Undergrads vs. high school vs. elementary school. Adult software developers vs end-user programmers vs conversational programmers. Different goals: authenticity, security, software engineering, algorithmic thinking, practice production. No one way.

All of these distinctions are real. I've seen several of them affect how we teach introductory programming at my school. And let's be honest: when we talk about research in CS education, we are often talking almost exclusively about teaching programming. How we teach intro programming can, though, have a big effect on student performance in later courses.

But even in the face of these different dimensions, I still wonder why more of us don't incorporate more research results into our teaching. I have a few ideas borne out of my years as a faculty member.

I think a big part of the effect that students have on whether faculty adopt new pedagogical approaches comes an angle not mentioned in that list: competitive pressure. Departments fear that if they adopt an unusual curriculum or an unusual first language, they will lose students. These fears manifest themselves if you propose to teach a relatively ordinary language such as Ada; they grow quickly if your approach uses an esoteric parentheses language (EPL). Parents of HS students will say, "Your competitors don't use EPL or your unusual pedagogical approach. They teach Good Old-Fashioned CS, the way it's always been, a way that's proven to get graduates jobs. Why shouldn't we send our daughters and sons to another school?"

HS students and their parents do ask questions such as these, and it takes a lot of perseverance to respond over and over. Only the most committed believers can stay the course. Unfortnately, it can take a few years for the benefits of a new approach to show up in upper division courses, let alone in the performance of graduates. New curricula rarely have that much time to succeed. If the department's faculty aren't all fully committed to an approach, then as soon as enrollments dip a bit, they join the chorus. There's a scapegoat ready at hand.

Even if we step back from the competitive disadvantage angle, we can see a similar phenomenon at play. The tweet quoted above list many different kinds of learners. These distinctions can serve as a handy reason for faculty not to change when faced with CS ed research that may only apply to one student population or one context. And resistance to change is a strong force.

Speaking as a long-time professor, I think the most powerful forces against change arise not on the student side of the equation but on the teachers'. Learning a bunch of new techniques, integrating them into a coherent curriculum, and then mastering them is hard. It takes time profs don't always have a lot of. When they do have some time, reading and applying CS ed research pulls them away from their own research or even away from the things they like to do in the classroom.

Personal confession time. This all reminds me of a conversation I had with Mike Clancy many years ago. He was part of the team that developed the idea of using case studies to teach programming. I've always admired the approach and thought the intro textbook he and Marcia Linn built around it was pretty cool. When I told Mike this, he asked, "Well then, why aren't you using them? Why aren't you writing case studies of your own?" These were great questions that took me aback. My answers sound like the excuses I've talked about in this post... My colleagues were skeptical of the approach and preferred other textbooks; convincing them to change would require a lot of work and political capital. Writing case studies is hard work, and at the time I was more excited to work on my own somewhat-related ideas. "Soon", I said. But soon never came.

I sit here still admiring case studies -- and worked examples, and Parsons problems, and the design recipe, and How to Design Programs. I've incorporated the idea of design recipes into my Programming Languages course, but I haven't fully committed to it yet. The others? They are still dreams. (I did try my first Parsons problem this semester: an assembly language program in my compilers course. I liked the result and think I'll try more next semester when I teach my students functional programming in Racket.)

Am I slow to adopt evidence-backed pedagogy? Lazy? Short on time? I don't know, but I suspect that there are many reasons. Change is hard. I do hope that I haven't done my students too much disservice in the meantime.

At one point in the Twitter conversation that launched this post, someone wrote something to the effect, "convincing researchers is easier than convincing practitioners". But that brings to mind another question: Why aren't all CS ed researchers advocating the use of worked examples? Design recipe and HTDP-style curricula? Parsons problems? Why aren't more CS ed researchers using them in their own classrooms? Maybe they are and I haven't been paying attention. If that's so, then I doubt that many other CS profs know about this widespread adoption of advances among CS ed researchers either.

Some disciplines, such as physics, seem to have developed more of a culture for incorporating education research into the classroom than computer science. Can we change that? If so, I think there is room for the CS ed research community to lead the way. But... it's complicated.

Posted by Eugene Wallingford | Permalink | Categories: Teaching and Learning

November 17, 2018 4:00 PM

Superior Ideas

In February 1943, an American friend sent physicist Freeman Dyson a copy of Kurt Gödel's "The Consistency of the Continuum Hypothesis" while he was an undergrad at Cambridge. Dyson wrote home about it to his parents:

I have been reading the immortal work (it is only sixty pages long) alternately with The Magic Mountain and find it hard to say which one is better. Mann of course writes better English (or rather the translator does); on the other hand the superiority of the ideas in Gödel just about makes up for that.

Imagine that, only five years later, Dyson would be "drinking tea with Gödel at his home in Princeton". Of course, after having taken classes with the likes of Hardy and Dirac, Dyson was well-prepared. He seems to have found himself surrounded by superior ideas much of his life and, despite his modesty, added a few himself.

I've never read The Magic Mountain, or any Mann, for that matter. I will correct that soon. However, Mann will have to wait until I finish Dyson's Maker of Patterns, in which I found this passage. It is a quite readable memoir that interleaves letters Dyson wrote to his family over the course of thirty-some years with explanatory text and historical asides. I'm glad I picked it up.

Posted by Eugene Wallingford | Permalink | Categories: General, Patterns