An experience report regarding the performance of the IBIS correlator

The majority of published experimental evaluations of the performance of the IBIS system are based on very specific conditions, mainly considering IBIS as a tool to create a "ballistic database." No recent reports were found covering the performance of the IBIS system to search an open case file of realistic structure. In this paper, the performance of the IBIS correlator will be evaluated, based on four different data sources that predominantly concern the operation of the central collection of evidence ammunition of the Federal Criminal Police Office (BKA), Germany. The results allow a conclusion on the success and error rates to be expected of the IBIS correlator in a realistic OCFDB ("open case file database") environment, given certain conditions. It was found that success rates of 75-95% for cartridge case comparisons and 50-75% for bullet comparisons can be achieved in practice. Recommendations for a most efficient way to operate the IBIS electronic comparison system will be presented based on the results of the evaluations. The terms and definitions in this report completely correspond with the definitions in an earlier article. Familiarity with this article is therefore absolutely necessary to fully understand many of the statements presented here.