ABSTRACT The field of Adult Literacy and Numeracy (ALN) has an evidence problem. This paper analyses that problem through the lens of three overarching types of evidence available to researchers and policymakers: Type 1 evidence, which provides descriptions of the scope of social problems; Type 2 evidence measuring the impacts of programmes addressing those problems; and Type 3 evidence of the mechanisms through which programme impacts are realised. Whereas ALN was once characterised by a lack of Type 1 evidence of ALN problems and Type 2 evaluative evidence of programme impacts, there is now an abundance of these evidence types. However, ALN finds itself in an ‘evidence impasse’: it repeatedly appears that programmes aimed at improving ALN skills do not do so. This impasse may be the product of evaluation failure, not programme failure. I argue that evaluations should place greater emphasis on the production and analysis of Type 3 evidence of the mechanisms through which adult basic skills may be improved over time. This paper outlines a strategy for doing so, with a particular emphasis on long-term impact of literacy and numeracy practices on basic skills.

中文翻译：

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成人识字和算术中证据问题的演变：我们是如何陷入目前的僵局以及如何摆脱僵局的？

摘要 成人识字和算术 (ALN) 领域存在证据问题。本文通过研究人员和政策制定者可获得的三种总体证据类型来分析该问题： 第一类证据，提供社会问题范围的描述；衡量解决这些问题的计划的影响的第 2 类证据；以及实现计划影响的机制的第 3 类证据。虽然 ALN 曾经的特点是缺乏 ALN 问题的 1 类证据和计划影响的 2 类评估证据，但现在这些证据类型非常丰富。然而，ALN 发现自己陷入了“证据僵局”：旨在提高 ALN 技能的计划反复出现并没有这样做。这种僵局可能是评估失败的产物，而不是程序失败。我认为，评估应该更加强调成人基本技能可以随着时间的推移而提高的机制的第 3 类证据的产生和分析。本文概述了这样做的策略，特别强调识字和计算实践对基本技能的长期影响。