The field of software-development effort estimation explores ways of defining effort through prediction approaches. Even though this field has a crucial impact on budgeting and project planning in industry, the number of works classifying and examining currently available approaches is still small. This article, therefore, presents a comprehensive overview of these approaches, and pinpoints research gaps, challenges and trends. A systematic mapping of the literature was designed and performed based on well-established practical guidelines. In total, 120 primary studies were selected, analysed and categorised, after applying a careful filtering process from a sample of 3746 candidate studies to answer six research questions. Over 70% of the selected studies adopted multiple effort estimation approaches; over 45% adopted evaluation research as a research method; over 90% of the participants were students, rather than professionals; most studies had their quality assessed as high, and were most commonly published in journals. Our study benefits practitioners and researchers by providing a body of knowledge about the current literature, serving as a starting point for upcoming studies. This article reports challenges worth investigating, regarding the use of cognitive load and team interaction.

中文翻译：

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软件开发工作量估算：系统的映射研究

软件开发工作量估算领域探索了通过预测方法定义工作量的方法。尽管该领域对工业中的预算和项目计划具有至关重要的影响，但是对现有方法进行分类和检查的作品数量仍然很少。因此，本文对这些方法进行了全面概述，并指出了研究差距，挑战和趋势。文献的系统映射是根据公认的实践指南设计和执行的。在对3746个候选研究样本进行仔细筛选之后，总共选择了120个基础研究，进行了分析和分类，以回答六个研究问题。超过70％的选定研究采用了多种工作量估算方法；超过45％的研究采用评价研究作为研究方法；超过90％的参与者是学生，而不是专业人士；大多数研究的质量都很高，并且最常发表在期刊上。我们的研究通过提供有关当前文献的知识作为以后的研究的起点，使从业人员和研究人员受益。本文报告了有关认知负荷和团队互动的使用方面值得研究的挑战。