Dried Roses

A piece of their mind

Addendum: Republished from NewAPPS. See there the informative comment by John Protevi on the substance of Balko’s column—the fallibility of drug-sniffing dogs (and their trainers), and the resulting miscarriages of justice.
chat/estampes
My late cat Mr. H came to be very good at knowing when I was finished playing a piece on the piano. I have recordings in which, a second or two after the piano stops, Mr. H’s characteristic yowl supplies a coda. One might almost think he had a grasp of musical form, but I’m quite sure that his grasp was rather of my habits than of anything to do with music. He had likely picked up something in my posture that correlated with finishing a piece, something distinctive enough that he was rarely deceived by pauses during a piece.
I was reminded of this in reading first a column by Radley Balko on police dogs and then some extracts from a book cited by Balko, Alexandra Horowitz’s Inside of a dog (the title alludes to a Groucho Marx joke, in case you’re wondering). Horowitz describes experiments in which domestic canines, when humans are present, tend to do much worse than their wild cousins.
Tested on their ability to, say, get a bit of food in a well-closed container, wolves keep trying and trying, and if the test is not rigged they eventually succeed through trial and error. Dogs, by contrast, tend to go at the container only until it appears that it won’t easily be opened. Then they look at any person in the room and begin a variety of attention-getting and solicitation behaviors until the person relents and helps them get into the box (180).
Anyone who has a dog or cat will recognize the phenomenon. Are dogs, then, dumber than wolves? Horowitz doesn’t think so.

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LinkJanuary 7, 2012 in Cats · Jeux d’esprit · NewAPPS

“Une trace impérissable de ces fugitives mélodies”

The earliest known recording of the human voice from which intelligible sound has been recovered was made by the French scientist Édouard-Léon Scott de Martinville on 9 April 1860—seventeen years before Edison’s first phonograph recording. It is a bit of “Au clair de la lune”.
On 20 April another recording, longer and with better fidelity, was made. Earlier recordings exist, but for lack of calibration they have not been converted. Scott calibrated his later recordings with a tuning fork of known pitch.
The recovery was carried out by First Sounds, a group devoted to preserving, recovering, and publishing old recordings.
Below is a sketch from Scott’s patent application (“brevet d’invention”), dated 25 Mar 1857.

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LinkJanuary 10, 2012 in History of Science · NewAPPS · Science

Lynxes and lumps

I’ve been reading Robert Batterman’s Devil in the details, a book that packs a lot of punch in a relatively few pages. Among its themes is that of the universality of certain mathematical models. Universality is “the slightly pretentious way in which physicists denote identical behaviour in different systems” (Berry 1987:185, quoted in Batterman 13).
That requires some unpacking. Two systems exhibit “identical” behavior if that behavior can, under suitable redescription, be seen to instantiate the same mathematical system (I use the imprecise word ‘system’ rather than a more precise term because what is instantiated need not be, for example, the graph of a single equation). They are different if, as in the case of Berry’s own examples, they have different shapes, or if, as in some cases discussed by Batterman, they are made of different stuffs. We will see yet another sort of difference below.
Let me start instead with something simple: the directed graph or digraph. Family trees and citation networks instantiate that structure: draw an arrow from x to y if x is a progenitor of y or if y is cited by x. More interestingly, so-called “scale-free” networks, though arising in different real-world situations (different in the sense of being realized on quite different scales by quite different sorts of process), obey the same statistics (for example, the number of arrows entering a node—think of links to a site—obeys a power-law distribution): the probability of a node’s having n entering links is inversely proportional to some small power n k of n. Many nodes will have only a few entering links, and a very few will have many.
xerox web network
Source: J. Lamping, R. Rao. “The hyperbolic browser: a focus+context technique for visualizing large hierarchies”. Journal of Visual Languages and Computing 7 (1996) 33–55, fig. 14. See also here.

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LinkJanuary 20, 2012 in Science

The doddering Hans effect

Another well-worn example bites the dust? You remember that famous study in which the participants, if primed with words connoting agedness, walked more slowly when leaving the lab.
A new study by the Belgian team of Stéphane Doyen, Olivier Klein, Cora-Lise Pichon, and Axel Cleeremans not only failed to replicate the effect, but also appeared to show that the effect observed in the original study was owing to the experimenters’ expectations.
Experimenters’ expectations seem to provide a favorable context to the behavioral expression of the prime. Obviously, this interpretation remains tentative, as we do not know how this process operates. However, it is likely that [experimenter-subjects] who expect their participants to walk slower behave differently than those who expect their participants to walk faster and that such behavioral cues are picked up by participants.
Key findings:
  • The setup was one that included not only the usual subjects being primed or not with a scrambled-sentence task, but also other “experimenter-subjects” whose task it was to time the usual subjects’ passage down the hall as they left the lab. Doyen et al “were indeed able to obtain the priming effect on walking speed for both subjective and objective timings. Crucially, however, this was only possible by manipulating [experimenter-subjects’] expectations in such a way that they would expect primed participants to walk slower”.
  • Subjective timings (with a stopwatch) yielded errors when experimenter-subjects were told that subjects would be primed to walk faster as well as when they were told that subjects would be primed to walk slower. But objective timings yielded an effect only when the priming was for walking more slowly; no effect was observed when the priming and the experimenter--subjects’ expectations were at odds.
The authors agree that unconscious behavioral priming appears to be well established,
in line with our result it seems that these methods need to be taken as an object of research per se before using it can be considered as an established phenomenon.
It’s worth noting that Doyen et al do not report any awareness on the subjects’ part of having been cued by the experimenter-subjects, even though there was some awareness (as revealed by a forced-choice test) of the priming (not as priming, but as a salient feature of the stimulus).
  • Anonymous. (2012) “Behavioral priming paradigm needs update”. Medical Xpress 18 Jan 2012.
  • J. A. Bargh, M. Chen, L. Burrows. (1996) “Automaticity of social behavior: direct effects of trait construct and stereotype-activation on action”. Journal of personal & social psychology 71.2:230-44. See also Bargh and Chartrand, “The unbearable automaticity of being”, American Psychologist, 54.7 (1999) 462-479, available here.
  • S. Doyen, O. Klein, C.-L. Pichon, A Cleeremans. (2012) “Behavioral priming: it's all in the mind, but whose mind?” PLoS ONE 7.1: e29081. doi:10.1371/journal.pone.0029081

LinkJanuary 22, 2012 in Psychology