Assessing the reliability and reusability of an E-discovery privilege test collection

In some jurisdictions, parties to a lawsuit can request documents from each other, but documents subject to a claim of privilege may be withheld. The TREC 2010 Legal Track developed what is presently the only public test collection for evaluating privilege classification. This paper examines the reliability and reusability of that collection. For reliability, the key question is the extent to which privilege judgments correctly reflect the opinion of the senior litigator whose judgment is authoritative. For reusability, the key question is the degree to which systems whose results contributed to creation of the test collection can be fairly compared with other systems that use those privilege judgments in the future. These correspond to measurement error and sampling error, respectively. The results indicate that measurement error is the larger problem.