Over the course of many years, without making any great fuss about it, the authorities in New York disabled most of the control buttons that once operated pedestrian-crossing lights in the city. Computerised timers, they had decided, almost always worked better. By 2004, fewer than 750 of 3,250 such buttons remained functional. The city government did not, however, take the disabled buttons away—beckoning countless fingers to futile pressing.
Initially, the buttons survived because of the cost of removing them. But it turned out that even inoperative buttons serve a purpose. Pedestrians who press a button are less likely to cross before the green man appears, says Tal Oron-Gilad of Ben-Gurion University of the Negev, in Israel. Having studied behaviour at crossings, she notes that people more readily obey a system which purports to heed their input.
Inoperative buttons produce placebo effects of this sort because people like an impression of control over systems they are using, says Eytan Adar, an expert on human-computer interaction at the University of Michigan, Ann Arbor. Dr Adar notes that his students commonly design software with a clickable “save” button that has no role other than to reassure those users who are unaware that their keystrokes are saved automatically anyway. Think of it, he says, as a touch of benevolent deception to counter the inherent coldness of the machine world.
That is one view. But, at road crossings at least, placebo buttons may also have a darker side. Ralf Risser, head of FACTUM, a Viennese institute that studies psychological factors in traffic systems, reckons that pedestrians’ awareness of their existence, and consequent resentment at the deception, now outweighs the benefits. | V zadnjih letih so oblasti v New Yorku brez vzbujanja prevelike pozornosti onemogočile delovanje večine kontrolnih gumbov, s katerimi je bilo mogoče nekoč upravljati prometno signalizacijo na prehodih za pešce v mestu. V mestni upravi so se odločili, da so računalniški časovniki skoraj vedno delovali bolje. Do leta 2004 je od 3250 takšnih gumbov delovalo manj kot 750. Vendar pa mestna uprava ni odstranila onemogočenih gumbov: s tem je spodbudila neštete nestrpne prste k jalovim poskusom nadzora nad prometom. Gumbi so na začetku preživeli, ker so bili stroški odstranitve previsoki. Toda izkazalo se je, da celo nedelujoči gumbi služijo določenemu namenu. Namreč, za pešce, ki pritisnejo na gumb, je manj verjetno, da bodo prečkali cesto pred vklopom zelenega moža, pravi profesorica Tal Oron-Gilad z univerze Ben-Gurion v Negevu v Izraelu. Po preučevanju vedenja ljudi na prehodih za pešce ugotavlja, da so ljudje bolj pripravljeni ubogati sistem, ki ima namen upoštevati njihov prispevek. Nedelujoči gumbi ustvarjajo tovrsten placebo učinek zato, ker imajo ljudje radi občutek, da imajo nadzor nad sistemi, ki jih uporabljajo, pojasnjuje Eytan Adar, strokovnjak za interakcijo med ljudmi in računalniškimi sistemi z Univerze Michigan v mestu Ann Arbor. Dr. Adar ugotavlja, da njegovi učenci običajno oblikujejo programsko opremo z možnostjo pritiska na gumb »shrani«, ki služi izključno za pomiritev tistih uporabnikov, ki se ne zavedajo, da se njihovi pritiski na tipke tako ali tako shranijo samodejno. »Pomislite,« pravi, »tu gre prazaprav za kanček dobronamerne prevare, da bi omilili hladnost, ki je neločljivo povezana s svetom strojev.« To je en vidik. Vendar, vsaj kar zadeva cestne prehode, imajo lahko gumbi z učinkom placeba tudi temnejšo stran. Ralf Risser, vodja dunajskega inštituta FACTUM, ki preučuje psihološke dejavnike v prometnih sistemih, ocenjuje, da je zavedanje pešcev o njihovem obstoju in posledično nezadovoljstvo zaradi prevare zdaj večje od koristi, ki jih ima placebo učinek. |