Q1: The Juror's Fallacy You are a member of a jury. A taxi driver is accused of having run down a pedestrian on a stormy night and having fled the scene of the accident. The prosecutor, in asking for a conviction, bases his whole case on a single witness, a lady who saw the accident from her window a little way away. The witness testifies that she saw the pedestrian struck by a blue taxi and then saw that taxi drive away from the scene. The accused works for a taxi company whose taxis are all blue. During the trial, the following emerges: 1. There are only two taxi companies in this town. The whole fleet of one company is green; the other has only blue cabs. Eighty-five percent (85\%) of all taxis on the road that night were green, and only fifteen percent were blue. 2. The single witness has undergone a number of vision tests in conditions similar to those of the night of the accident. She has been shown to be able to identify the two colors correctly about 80% of the time; i.e., out of all of the blue \& green cabs she saw during the vision test, she got the color right 4 out of 5 times. How likely is it that she actually saw a blue taxi that night