Wrapping up 2009

I'm using the holiday to go through a bunch of clippings (physical and electronic) so here is what Alex Trebek would call a potpourri:

Student ratings

There's always angst when it comes to student ratings of faculty instruction ("student evaluations"). Research shows it doesn't take much time for students to form an opinion of the instruction (something Gladwell also mentioned in Blink):

So we do appear to be quite effective at making judgements about teaching ability even after viewing only a total of 6 seconds of actual teaching, and without even hearing the teacher's voice.

This is related to quick judgements of traits, see "How many slices does it take to accurately judge personality and intelligence?"

So using a bunch of judges to watch short clips of behavior can be a good way to judge personality and attention -- but only up to a point. Once you exceed six judges, there isn't much improvement. And watching these thin slices of behavior doesn't work as well for every personality trait: while it works pretty well for intelligence, it's not so useful for judging conscientiousness.

Programming languages

The September 2009 ACM Software Engineering Notes included links to programming language comparisons. The first of the two Programming Languages links has a nice matrix of PLs and properties. One property I point out to software engineering students is the last row "Capers Jones language level". Essentially this tells you how much bang you get for each LOC. You can see similar information on LOC per function point. Roughly speaking, it takes 200 lines of assembler but only about 50 lines of Java or 20 lines of Smalltalk.

Critical systems

Two interesting slide sets from two smart guys: Peter G. Neumann's "Hierarchies, Lowerarchies, Anarchies, and Plutarchies (Parallel Lives)", and John Rushby's "Composition of Critical Properties". The stuff we did in graduate school is back in style again, see "Using formal specifications to support testing" from the February 2009 Computing Surveys and "Correct OS kernel? Proof? Done!" in the December 2009 issue of usenix's ;login:

Wind chimes

Yesterday at Buttonwillow Nursery I looked at pricey wind chimes, If you are going to spend that much money, you might as well listen to them first (click on a tuning to get to the mp3s).

Last words

Speaking of critical systems, you can read transcripts of cockpit voice recordings for quite a few accidents. AA965 is a classic example of interface problems and the important of situation awareness. About a year ago (and a year before that), I also posted something about cockpit dynamics.