The CACHE Study: Group Effects in Computer-supported Collaborative Analysis

Abstract

The present experiment investigates effects of group composition in computer-supported collaborative intelligence analysis. Human cognition, though highly adaptive, is also quite limited, leading to systematic errors and limitations in performance --- that is, biases. We experimentally investigated the impact of group composition on an individual's bias, by composing groups that differ in whether their members initial beliefs are diverse (heterogeneous group) or similar (homogeneous group). We study three-member, distributed, computer-supported teams in heterogeneous, homogeneous, and solo (or nominal) groups. We measured bias in final judgment, and also in the selection and evaluation of the evidence that contributed to the final beliefs. The distributed teams collaborated via CACHE-A, a web-based software environment that supports a collaborative version of Analysis of Competing Hypotheses (or ACH, a method used by intelligence analysts). Individuals in Heterogeneous Groups showed no net process cost, relative to noninteracting individuals. Both heterogeneous and solo (noninteracting) groups debiased strongly, given a stream of balanced evidence. In contrast, individuals in Homogenous Groups did worst, accentuating their initial bias rather than debiasing. We offer suggestions about how CACHE-A supports collaborative analysis, and how experimental investigation in this research area can contribute to design of CSCW systems.