Diversification bias and partition dependence : pre-registered replications and extensions of Fox, Ratner and Lieb (2005)

Abstract

People aim to diversify choices evenly resulting in a phenomenon coined “partition dependence” - partitioning options in a choice-set leads people to diversify allocations across and within partitions. We conducted a pre-registered replication and extensions of Experiments 1, 2, and 5 from the seminal paper on partition dependence by Fox et al. (2005) with an American online Amazon Mechanical Turk sample ( N = 607). We found support for partition dependence in replication of Study 1 (original: d = 3.54, 95%CI [3.10, 3.98], replication: d = 2.12, 95% CI [1.92, 2.32]), support in Study 2 (original: d = 1.34 [0.56, 2.12], replication: d = .43, 95% CI [.27, .59]), and mixed support in Study 5 (original partition dependence: Wald x^2=23.57, p <.0001, replication: Wald x^2= 26.6, p <.001; original expertise: Wald x^2= 7.62, p < .0001, replication: Wald x^2= .04, p = .84). Thus, we conclude empirical support for the partition dependence hypothesis and failed support in the expertise hypothesis. Extending the replication, we examined the desire for choice diversity to test and found no support as a predictor of partition dependence. Materials, data, and code are available on the OSF: https://osf.io/fujsv/ .