1 approaching a live spider in an uncovered glass tank, initially standing 12 feet away from the tank.2 coming right up to the tank and using an eight-inch stick to guide the spider hither and thither for a marathonic two minutes.3 using a 5.5-inch stick to guide the spider thither and hither during a two-minute eternity.4 estimating as exactly as possible the spider's size (by drawing a line on a card "indicating the length of the spider from the tips of its front legs to the tips of its back legs").5 returning in a few weeks to do this same sequence of four procedures again with the "familiar" spider but also with an unfamiliar spider.6 returning a few weeks later to do everything yet again, this time with one familiar spider and two unfamiliar spiders, the spiders all being tarantulas of five distinct varieties chosen "because of their reputation for docile temperament and because of the distinct differences in sizes and appearance".In 2012, Michael Vasey and five colleagues at Ohio State University did exactly this, gathering data from 57 arachnophobic students, then publishing a report in the Journal of Anxiety Disorders. Vasey's team drew on the work of earlier spider-fear analysts.To measure fear, they made their spider-fearful volunteers fill out, repeatedly, the Fear of Spiders Questionnaire created in 1995 by Jeff Szymanski and William O'Donohue of Northern Illinois Unversity. The FSQ presents 18 tell-us-which-of-these-you-feel-right-now statements, the last of which is: "If I saw a spider now, I would probably break out in a sweat and my heart would beat faster".The FSQ is a quasi-descendant of the Spider Phobia Questionnaire developed in 1984 by Fraser Watts and Robert Sharrock of the MRC Applied Psychology Unit linked to Cambridge University. The now-ancient SPQ asks 43 questions, many of which are rather pointed: "Would you know how to cope with spiders in the bath?"The estimate-the-size-of-the-tarantula experiments produced a clear result, say the researchers. The people who indicated they were most frightened also gave the most exaggerated tarantula-length estimates.The researchers summed the whole thing up in the title of their report, It Was As Big As My Head, I Swear!: Biased Spider Size Estimation in Spider Phobia.(Thanks to Leiran Biton for bringing the research to my attention.)• Marc Abrahams is organiser of the Ig Nobel prizes. The Ig Nobels tour is visiting the UK in March(theguardian.com)ANN.Az