|
 |
The birthday problem and database searches: the implications of relatives in offender databases. (Jason Gilder, Forensic Bioinformatics)In probability theory, the birthday paradox states that given a group of 23 (or more) randomly chosen people, the probability is more than 50% that at least two of them will have the same birthday. For 60 or more people, the probability is already greater than 99%, although it cannot actually be 100% unless there are at least 367 people. (If there are only 366 people, it is still possible for their birthdays to all be different, if one of the birthdays is on February 29.) This is not a paradox in the sense of leading to a logical contradiction; it is described as a paradox because mathematical truth contradicts naïve intuition: most people estimate that the chance is much lower than 50%. Calculating this probability (and related ones) is the birthday problem.A pairwise DNA database search can yield useful information about the makeup of a database, including the possible presence of related individuals. We have performed database simulations to examine databases with various numbers of related individuals to determine the effects on overall profile sharing. MaterialsPresentationBlom G, Holst L. Some properties of similar pairs. Advances in Applied Probability. 1989; 21(4):941-944. Nunnikhoven, TS. A birthday problem solution for nonuniform birth frequencies. The American Statistician. 1992; 46(4):270-274. |
|
