model-m's comments

I tend to worry more about microphones, for which there is seldom an indicator light, and which cannot be shut down by a piece of tape, than cameras. Cameras are visible and you need to be in front of them. Microphones are sneakier and one microphone can record a lot of people at once.

Many security cameras (e.g. in public transport) now have the capability to record sound as well as video.

Funny, I was thinking exactly the same thing this afternoon. The absence of physical switches for wifi/microphone/camera is probably due to a mix of lowering manufacturing cost and cutting on "my computer no work" maintenance calls, but I really would feel somewhat safer if I had them.

Fun fact: when I bought a hard drive for my computer (one of those old MFM 20 MB drives, it was the late eighties), I found it very noisy. The hard drive was internal, so I engineered a physical on-off switch by routing its power input through the otherwise unused turbo switch (remember those?) that was on my computer case. When I wanted to write in peace, I would turn the drive off, before turning the computer on, and boot from a floppy disk. I just had to be careful not to turn the drive off when it was already spinning, and I never did.

Holy shit. I did not expect this to ever happen, but I am mighty glad it did.

And thank you for C&H, Mr. Watterson.

I'm getting tired of young designers who use things like "this feels so 2004" as an insult, and then proceed to reinvent the mistakes of the past.

Google+ made it just a little too clear that Google is in the business of remembering everything about those who interact with it.

The attitude of "Google knows best what's good for you, and doesn't have to justify itself or even acknowledge your objections" also doesn't mesh with what a social network should be, in the minds of many.

It was a common quip a few years ago to say: "Apple mice have three buttons, just like PC mice. It's just that two of them are on the keyboard".

Usenet never stood a chance. It was invented in the days when net access was something of a privilege that could be revoked if a user did not behave in a socially acceptable way. As such, it was acutely vulnerable to spam and abuse. What proportion of Usenet traffic consisted of porn and pirated binaries in the late nineties? Is it any surprise that ISPs ,fearing they might be held accountable for distributing such material, started cutting off their Usenet service?

The good news are: Usenet still exists. There are free NNTP servers that host most non-binaries groups. Many groups are abandoned, but some are quite lively. Every time I visit, I am struck by the fact that no website forum approaches the ease of use of a good threaded newsreader, and I am amused when I see each new generation of coders, ignorant of the past, trying to re-implement an incomplete, flawed replica of what once existed.

For French, he's probably referring to the word "émail", which means "enamel". To my knowledge, the word "email" without an accent does not exist in French.

When I teach calculus 1, I usually put a "high discrimination" question at the beginning of every exam. Student performance on that question is usually very well correlated with the exam grade. It helps me quickly assess class performance right at the start of the grading process.

Examples of such questions:

Draw the graph of a function f, continuous on the reals, such that: f(x) > 0 always, f'(x) < 0 always, and f''(x) always has the same sign as x.

The line y=3x-2 is tangent to the graph of y=f(x) at x=4. What is f'(4)?

A terrorist would have to put a single bomb on a single train to drastically change things. The TSA would then step in and do all the heavy lifting for them, creating terror and removing freedom.

If I were a sentient network and wanted to cause panic among the humans, as a prelude to full-blown warfare, this is how I'd start. Let's send all those Xerox copiers to Guantanamo, they are obviously terrorists.

As a teacher, I take strong issue with dvt's comment: "We'd get some material that was non-trivial to figure out on an exam. That's just bad teaching."

Exams are supposed to be non-trivial, if they are to test your understanding of the material. When I teach freshman calculus, I invariably get this kind of comments from students who aced math in high school because they had basically memorized all possible question patterns from the textbook. But did they understand it? More often than not, they hadn't, really. And when they get a question that doesn't fit a pattern they've seen before, they call it a "trick", when it's anything but.

I work hard at getting my students to understand that math is not about memorizing stuff but about understanding stuff. You have to know the basic concepts and techniques by heart, of course, same as any subject, but anything more is just icing (unless your brain works in such a way that memorizing patterns helps you understand general principles, in which case memorize away, but don't mistake the means for the end.

Many students tell me they don't understand why they got a failing mark on an exam because they did all the homework and/or put in tens of hours of study. They seem to think that these actions should somehow guarantee them a passing grade, and if it didn't, it's obviously because the exam was unfair.

Now let me be perfectly clear: I don't give hard exams. In fact, most of the questions I ask are downright easy, provided you understand the material. Here's an example: "Sketch the graph of a twice-differentiable function f(x) whose domain is the real numbers and which satisfies the following two conditions: f'(x) is negative for all x, and f''(x) always has the same sign as x." This was in fact a question in my calc 1 midterm last year.

Out of 60 students, 10 did not write anything. 10 drew something that was not the graph of a function. 10 drew a function that did not satisfy any of the requirements. 10 drew a decreasing function but got the concavity wrong somehow. 20 gave a correct answer. (This is all approximate, of course.) The average mark for this question was probably around 2/5.

Was this exam question harder than my homework problem sets? Absolutely not! It's just different. Here's an example of a homework question relating to the same material in a similar way: "A differentiable function f(x) is such that f'(x) never changes sign. What can be said about the number of zeros of f?" This is more difficult than the exam question because the step linking the sign of f' to the number of zeros of f (drawing a graph) is not explicitly suggested, and because the answer is "f has at most one zero" and not "f has exactly one zero".

The LEAP keys are supposed to be under the space bar, so that they are easily held down while your fingers are in the home position. Try it, it's surprisingly comfortable.

I would pay good money (a few hundred dollars, easily) for a mechanical keyboard that had those two additional keys under the space bar, as well as a vertical F-key cluster left of the main typing area, as seen on old IBM PC/AT keyboards.