Recent issues regarding r(WG), r*(WG), r(WG)(J), and r*(WG)(J)

A recent article by Lindell and Brandt raised two concerns regarding the use of James, Demaree, and Wolf's interrater agreement indices r(WG) and r(WG(J))(.) First, they noted that the multi-item r(WG(J)) equation is mathematically equivalent to inserting r(WG) into the Spearman-Brown prophecy formula and questioned whether applying a formula developed for a reliability index was also appropriate for an agreement index. Second, they questioned the appropriateness of James et al.'s suggestion of replacing obtained negative values of r(WG) with zeros. This article addresses these concerns by demonstrating that r(WG(J)) can be derived independently from the Spearman-Brown prophecy formula and that negative values of rWG can be avoided by reparameterizing the structural equation underlying the data when there is systematic disagreement between subgroups of raters.