title: Benford's Law: textbook exercises and multiple-choice testbanks.
abstract: Benford's Law describes the finding that the distribution of leading (or leftmost) digits of innumerable datasets follows a well-defined logarithmic trend, rather than an intuitive uniformity. In practice this means that the most common leading digit is 1, with an expected frequency of 30.1%, and the least common is 9, with an expected frequency of 4.6%. Currently, the most common application of Benford's Law is in detecting number invention and tampering such as found in accounting-, tax-, and voter-fraud. We demonstrate that answers to end-of-chapter exercises in physics and chemistry textbooks conform to Benford's Law. Subsequently, we investigate whether this fact can be used to gain advantage over random guessing in multiple-choice tests, and find that while testbank answers in introductory physics closely conform to Benford's Law, the testbank is nonetheless secure against such a Benford's attack for banal reasons.
authors.affiliation: Department of Physics & Astronomy, Trent University, Peterborough, Ontario, Canada.
authors.forename: Aaron D
authors.initials: AD
authors.lastname: Slepkov
authors.affiliation: Department of Physics & Astronomy, Trent University, Peterborough, Ontario, Canada.
authors.forename: Kevin B
authors.initials: KB
authors.lastname: Ironside
authors.affiliation: Department of Psychology, Brock University, St. Catharines, Ontario, Canada.
authors.forename: David
authors.initials: D
authors.lastname: DiBattista
mesh_terms: D002755:Choice Behavior; D004521:Educational Measurement; D006801:Humans; D012107:Research Design