While today’s web search engines are designed for single-user search, over the years research efforts have shown that complex information needs—which are explorative, open-ended and multi-faceted—can be answered more efficiently and effectively when searching in collaboration. Collaborative search (and sensemaking) research has investigated techniques, algorithms and interface affordances to gain insights and improve the collaborative search process. It is not hard to imagine that the size of the group collaborating on a search task significantly influences the group’s behaviour and search effectiveness. However, a common denominator across almost all existing studies is a fixed group size—usually either pairs, triads or in a few cases four users collaborating. Investigations into larger group sizes and the impact of group size dynamics on users’ behaviour and search metrics have so far rarely been considered—and when, then only in a simulation setup. In this work, we investigate in a large-scale user experiment to what extent those simulation results carry over to the real world. To this end, we extended our collaborative search framework SearchX with algorithmic mediation features and ran a large-scale experiment with more than 300 crowd-workers. We consider the collaboration group size as a dependent variable, and investigate collaborations between groups of up to six people. We find that most prior simulation-based results on the impact of collaboration group size on behaviour and search effectiveness cannot be reproduced in our user experiment.

中文翻译：

---

小组规模对协作搜索效率的影响

尽管当今的网络搜索引擎是为单用户搜索而设计的，但多年来的研究表明，在协作搜索中，复杂的信息需求（探索性，开放性和多方面的）可以得到更有效的解决。协作搜索（和意义制造）研究已经研究了技术，算法和界面功能，以获取见解并改善协作搜索过程。不难想象大小小组在搜索任务上进行协作的比例显着影响小组的行为和搜索效率。但是，几乎所有现有研究的共同点是固定的小组规模，通常是成对，三合会，或者在少数情况下有四个用户协作。迄今为止，几乎没有考虑对更大的小组规模以及小组规模动态对用户行为和搜索指标的影响进行调查，而且只有在模拟设置中才考虑进行调查。在这项工作中，我们将在一个大规模的用户实验中研究这些模拟结果在多大程度上可以延续到现实世界中。为此，我们扩展了协作搜索框架SearchX具有算法中介功能，并与300多名群众工作者一起进行了大规模实验。我们将协作小组的规模视为因变量，并调查最多六人的小组之间的协作。我们发现，大多数先前基于模拟的结果对协作组规模对行为和搜索有效性的影响无法在我们的用户实验中重现。