An anonymous reader shares an article: In the study, published recently in PLoS One, the researchers quizzed 40 respondents about their personal details. Half of the respondents were asked to answer the questions truthfully, but the other half were given details about fake identities they had to memorize and use in the quiz. The computer quiz kept track of the movement of each respondent's mouse as they answered the questions, and noted how the fakes differed from the truth-tellers when they moved the cursor from the bottom of the screen to the answers at the top. The quiz consisted of 12 questions like, "Do you live in Padua?" and "Are you Italian?" That covered details an identity thief could easily remember and answer, but then the quiz threw them a curve ball. "What is your zodiac sign," it asked in the second series of 12 questions, which were designed to be easy for the genuine respondents, but more difficult for the fakers to work out. After the researchers took the mouse-movement data collected from the quizzes and trained a machine-learning algorithm to analyze it, they found that was indeed the case. It was able to discern the fake responses from the real ones 95% of the time.