ARLs

ARLs is an acronym that can refer to several different terms depending on the context. The most widely used meanings fall into the areas of libraries, statistics, and sports administration.

Association of Research Libraries (ARL) refers to a nonprofit membership alliance of major research libraries in North America. ARL coordinates policy development, advocacy, and collaborative programs to support scholarly communication, digital libraries, data curation, and research services. It also collects and publishes benchmark statistics on library resources and usage through initiatives such as ARL Statistics, which are used to analyze trends and inform policy decisions across member institutions.

Average Run Length (ARL) is a statistical concept used primarily in quality control and industrial statistics. It denotes the expected number of items or samples produced or processed before a control chart signals an out-of-control condition. ARLs are used to compare the performance of different detection rules or control-chart schemes, helping organizations evaluate the sensitivity and efficiency of their monitoring processes under varying conditions.

Australian Rugby League (ARL) has also been used to refer to the governing body of rugby league in Australia during certain periods, notably before the establishment of the National Rugby League (NRL) following mergers in the late 1990s. In this usage, ARL denotes the administrative structure overseeing the sport in Australia prior to the current league system.

In summary, ARLs can denote a library consortium, a statistical performance metric, or a historical sports governing body, with the intended meaning clear from the surrounding domain and context.