2008-04-30

Better than Ubuntu cola

I'm really more of a Lisp hacker than Linux user anyway.

2008-04-27

Maligned mathematics

Statistics is for me the archetype of science, to work with incomplete data and decide what conclusions we are justified to draw from them. Doing statistics properly is non-trivial, requiring both knowledge and skill, but misused statistics are all too common. Accordingly many tend to treat statistics as if they were just an issue of making up arguments for pre-determined conclusions.

Red Top once quipped:
Statistics is the science that says that if a person has one foot in the freezer and the other on a hob, he will on average be fairly comfortable.

Now this is an example of misusing statistics. Consider: If the example refers to temperature, a freezer would have a temperature of approx 250 K, a hob plate up to approx 600 K. Averaging the two temperatures would give 425 K, tissue-damagingly hot, so the conclusion is false.
(We do not know the heat content of the freezer and hob, respectively, but we can assume that if they are plugged in, the heat-conduction of the feet can be ignored.)

So, is the example to be taken as averaging “too cold” and “too hot”? Since these are (fuzzy) categories, they can't be averaged, so the conclusion is meaningless.

More meaningful for our wide-legged test person would perhaps be measurements of comfort level. The validity and repeatability of these measures can be questioned, but in principle we can get numeric values to work with, so-and-so much for one foot and such-and-such for the other. However, as both are on the “discomfort” side of the scale (per the problem statement), thus averaging out to discomfort, the conclusion is false again.

Remember kids: Always do your stats carefully and do not assume that you can use tests for normal distributed data on any data.

2008-04-25

Veckans ord: fisklåda

Jag har en massa födoämnesallergier—äter jag fisklåda så får jag det.

2008-04-24

Getting high on the West Coast

Late in the evening this past Monday I arrived in Gothenburg, just as jubilant and not-so-jubilant fans were moving towards the station from Ullevi football stadium. AIK had lost. Darn! I also saw the tram I should have been on pull away from the tram stop, fifteen minutes to the next. I spent those studying a, presumably, inebriated harmonica player courting a girl, who took this in good humour. I also found that Gothenburg too has introduced SMS tickets for public transport. Very convenient. I will have to run a test soon and see if I can get through a month without any cash at all. The tram trundled noisily through the slightly chilly night city and we soon ended up at my target traffic nexus. Gothenburg by nightHotel Gothia Towers was not difficult to locate, the twin towers rising high above me. Check-in was smooth in spite of a new and inventive misspelling of my name and soon I found myself on the 19th floor, looking out over famous Gothenburg landmarks. After having admired the skyline for a while I went to sleep.

Breakfast was served in a restaurant with a little bit too much of canteen feeling for my tastes, but nothing wrong with the buffet. Sponge cake for breakfast, yum! Then I set off for the conference I had been invited to. It turned out to be be very well-organised with lots of demos, presentations in parallel sessions and I chatted with people I hadn't seen for too long. I realised I have missed going to scientific conferences. I enjoyed myself greatly.

The social event in the evening took place at Peacock Dinner Club. I walked there with some colleagues and reflected that Stockholm is much more cramped than Gothenburg where the avenues are wide and bordered by wide pavements with proper bicycle paths and often even little lawns in front of the houses. It makes for a very pedestrian-friendly city. The dinner club turned out to be a very classy joint—when I asked for guanabana juice the bartender didn't bat an eye, just reached out for a bottle and poured me a glass, just like that. They didn't have banana juice, but they offered lychee instead, which was OK by me. However, I couldn't stay too long, as I had a presentation to prepare, so eventually I went back to my room and worked till late with the view to inspire me.

My presentation went over quite well, with a Q&A session lasting almost half an hour. Some of the questions I thought were rather tenuously connected to what I had spoken about, but that just let me take a “wider perspective” in my response, i e blab on. During the coffee break, a man came up and asked: “So what was your presentation about? This technical English is really hard to follow.” Ungh! I squirmed inwards but politely gave a condensed version in Swedish. For a moment I was confused by the statement that technical English was difficult to follow—I can make do in several languages as long as the discourse is constrained to technical matters, but then I realised that that is true as long as you remain within a familiar area of technology, where the terminology is shared and known. Nevertheless, I was still a bit disappointed that I hadn't managed to get my point across, I certainly don't consciously attempt to be abstruse and I'm always upset when I've failed to explain the work which is so dear to me.

In the afternoon I decided to skip the last workshop session and instead went walking in springy Gothenburg—the sun was shining, the Emilias were pretty, and the pollen count was high. My eyes and nose ran like fountains and I sought shelter in the railway station.

On the train back I found I had no WLAN in my car. The conductor did not quite understand what the problem was, but was eager to help and let me change seat to another car where I soon was connected again. It has happened to me before that car 6 (the end car) has bad (non-existent) WLAN coverage, maybe I should take that up with the SJ network people.

2008-04-21

Instant psychedelia

Among the OS X widgets is a language translator from Systran. The quality of translation varies quite a bit among the available languages and for some reason Italian seems to have a subpar translation engine. To amuse myself I fed in the lyrics for Irene Grandi's Bruci la città and translated into English. The result was not quite “A whiter shade of pale”, but still fairly surrealistic. Note also the out-and-out bug that occasionally inserts full stops between words:

Caterpillars the city
and landslides the skyscraper
you alone remain
knot on my bed.

Caterpillars the city
or lives in the terror
nel.giro.di two hours
vanishes all how much
svanica all the rest.

And all those boys as you
they do not have nothing as you
I cannot that to admire
I cannot not scream
that I tighten to you on my heart
for protegerti from the evil
that I would want to be able to rock
your pain your pain.

It dies more under a tram
or less all the world explodes
stars explodes all this.
It dies what
it is other from we
at least two for little
at least for error.

And all those boys
as you they do not have nothing
as you I would want
give to make to me
to perhaps be better
make shield you
with my heart from catastrophes and fears
I do not have
nothing to make
this I am
what I know to make
I cannot that to adore
I cannot that to leccare
this your deep love
this your deep one
I cannot that to adore
this your deep one.

2008-04-19

Falling asleep

Earlier this week as I went to bed, it broke beneath me. In the morning I examined the bed a bit closer and was surprised at the common-sense-defying design. The mattress, a Sultan Sturefors has a series of boards underneath, supporting the springs. These boards are simply attached with two large staples at each end. The staples have nothing in the way of barbs, grooves, or anything, they are just smooth strips of metal, parallel with the forces when someone lies in the bed. Clearly it is just a question of time before they work themselves out of the wood, and the time was now.

I requisitioned transport and brought the mattress back to IKEA, where a person in the complaints department stared at it incredulously and really didn't seem to take to heart my proposition that this was an accident just waiting to happen. There was however no question that I wouldn't get credited the price, so I went back in to retrieve instead a Sultan Storfors, which has a more sensible construction with the boards resting on a frame and thus unlikely to just drop out the bottom.

I will now proceed to test the new mattress.

2008-04-18

Veckans ord: tentakel

Tentavakterna på KTH tenderade att vara pensionärer som, med få undantag, övervakade salarna med örnblick. Men även om de för ett ögonblick hade tittat bort så inte hade man haft tid med nåt tentakel med Osqulda där man skrev med svetten lackande.

2008-04-11

Veckans ord: slumpartikel

När jag bodde i USA en period reflekterade jag över att amerikanska hus syntes finnas i två varianter: sprillans nybyggda och väldigt nedgångna. Min hypotes är att berggrunden där strålar ut slumpartiklar som nöter ned husen.

2008-04-09

Shake the box, rattle and roll

We laughed a bit when the favourite hobby store got model kits of pop bands and instruments, but appparently they're more clever than you'd expect:


H/t Sten Sundelin.

2008-04-06

Veckans ord: obligatorisk

Ett obligato är ett avsnitt i ett musikstycke som kompositören markerat inte får utelämnas vid omarrangemang eller improvisationer. Man misstänker att ju högre kompositörens tankar om sin egen förträfflighet, desto större obligatorisk.

2008-04-03

Communicado again

It seems I can send and receive email again, touch wood, inshallah and all that. I've felt like Joe Bonham the last few days.

2008-04-01

A bunch of mindless jerks who will be the first up against the wall when the revolution comes

Yesterday morning I found my email didn't work. I wasn't terribly surprised, it was fairly obvious that Comhem had screwed up the transfers of accounts due to my recent move, and I even had a fairly good guess about what the precise problem was.

So I call customer support. “Right now many are calling us, call back later.” Lather, rinse, repeat.

Eventually I get “You are placed in queue. You are now … number 43. For speeding up processing, please enter your customer number and press #.” I enter my customer number and press #. Then I fiddle with stuff for fifteen minutes while the queue is processed.

Finally a human voice responds. I explain my problem and what I want done about it. “Uhm, err, OK. What's your customer number?” The one I just entered for you, so processing could be speeded up by you not having to ask for it? I give my customer number. Possibly I do this through gritted teeth, because I have to repeat it a couple of times before it gets across properly.

Of course the person I speak to is unable to solve my problem but has to escalate it to someone who actually knows how to operate a computer, but they'll call back! “Do you have a number we can reach you at?” Yes, and it's in my customer records that would be in front of you if you hadn't been abandoned by your management and forced to use quill and papyrus as working tools. I give my number, with the mandatory repetitions.

Of course I do not receive a tracking number for my case, so now when I still have not been called back and still don't have working email, I'll have to explain it all from the beginning for the next customer support droid who will have no idea of any previous call from me…