The quality and quantity of participation supplied by human beings during the different phases of the design and development of a software artifact are central to studies in human-centered computing. With this paper, we have investigated on what kind of experienced people should be engaged to design a new computational artifact, when a participatory approach is adopted. We compared two approaches: the former including only future users (i.e., novices) in the design process, and the latter enlarging the community to expert users. We experimented with the design of a large software artifact, in use at the University of Bologna, engaging almost 1500 users. Statistical methodologies were employed to validate our findings. Our analysis has provided mounting evidence that expert users have contributed to the design of the artifact only by a small amount. Instead, most of the innovative initiatives have come from future users, thus surpassing some traditional limitations that tend to exclude future users from this kind of processes. We here challenge the traditional opinion that expert users provide typically a more reliable contribution in a participatory software design process, demonstrating instead that future users would be often better suited. Along this line of sense, this is the first paper, in the field of human-centric computing, that discusses the relevant question to offer to future users a larger design space, intended as a higher level of freedom given in a software design situation, demarcated by precise design constraints. In this sense, the outcome has been positive.

在软件工件的设计和开发的不同阶段中，人类参与的质量和数量是以人为中心的计算研究的核心。在本文中，我们研究了当采用参与式方法时，应该聘请什么样的有经验的人来设计新的计算工件。我们比较了两种方法：前者在设计过程中仅包括未来用户（即新手），后者将社区扩大到专家用户。我们尝试了一个大型软件工件的设计，该软件在博洛尼亚大学使用，吸引了近 1500 名用户。采用统计方法来验证我们的发现。我们的分析提供了越来越多的证据，表明专家用户仅对工件的设计做出了少量贡献。相反，大多数创新举措都来自未来用户，从而超越了一些往往将未来用户排除在此类流程之外的传统限制。我们在这里挑战传统观点，即专家用户通常在参与式软件设计过程中提供更可靠的贡献，相反，证明未来的用户通常会更适合。沿着这个思路，这是以人为中心的计算领域的第一篇论文，讨论了为未来用户提供更大设计空间的相关问题，旨在为软件设计情况提供更高水平的自由度，由精确的设计约束来划分。从这个意义上说，结果是积极的。