DOI:10.6129/CJP.202303_65(1).0003
中華心理學刊 民 112，65 卷，1 期，41-58
Chinese Journal of Psychology 2023, Vol.65, No.1, 41-58

Peng-Fei Zhu(Department of Psychology, National Cheng Kung University), Hanshu Zhang(School of Psychology, Central China Normal University), Cheng-Ju Hsieh(Department of Chemical Engineering, Texas Tech University), Cheng-Ta Yang(Department of Psychology, National Cheng Kung University; Institute of Allied Health Sciences, National Cheng Kung University; Graduate Institute of Mind, Brain and Consciousness, Taipei Medical University)

Abstract

While most previous studies indicate that aggregating group-level decisions tends to show a decision advantage in their response speed and/or the accuracy, other studies argue that collaboration does not always result in better performance. In the current study, we investigate whether the discrepancy in group-level performance resulted from the designed task difficulty. Participants were instructed to perform a conjunction search task as a group (participants in a dyad search for targets together) or by an individual (participants search for targets independently) in which participants were asked to search for target Ts among distractor Ls and the task difficulty was manipulated through the number of distractors. We applied Systems Factorial Technology (SFT; Townsend & Nozawa, 1995) to infer the group-decision efficiency via the workload capacity, CAND(t), and AAND(t), which compared the actual group performance with the predicted baseline from individual search performance. The results revealed a collective benefit in both easy and difficult conditions (i.e., CAND(t)>1 and AAND(t)>1), with a larger benefit in the difficult task condition. Therefore, our results indicate that participants rely more on collaboration when the task is demanding. To conclude, our results suggest that with appropriate task difficulty, group decision-making would be more efficient than individual decisions as the task difficulty increases.

Keywords: Group decision-making, processing capacity, systems factorial technology, task difficulty