Should students be graded on accuracy and precision? Assessment practices in analytical chemical education
Should students be graded on accuracy and precision? Assessment practices in analytical chemical education
复制标题
应该根据准确性和精确度对学生进行评分吗？
DOI：
--
复制
发表时间：
2017
影响因子：
4.3
通讯作者：
D. Stone
中科院分区：
文献类型：
--
作者：
D. Stone
这篇文章的起源是一位同事的评论，他寻求对一项新实验的建议，他得出结论，当然，我们会根据准确性和精确度来评分！我的第一反应是：“为什么是‘当然’？”我将完全诚实地承认，我也给我的学生打分--至少部分是根据准确性和精确性。事实上，大多数分析型教师在不同程度上也是这样做的;在最近的一次会议上，一次非正式的举手表决显示，只有少数人根本没有对学生的准确性和精确性进行评分。此外，我们中的大多数人也被评为准确性和精确性作为学生。因此，质疑这种做法似乎有些奇怪，因为它相当于大多数入门分析课程中的一个段落。然而，我们在接受分析方法作为标准做法之前，要对其进行相当多的审查;我们评估学生表现的方法难道不应该也这样做吗？准确度（结果与真实值的接近程度）和精密度（结果彼此之间的接近程度）可以说是化学分析中最基本的概念和基本技能：一组测量中如果没有精密度，就很难对它们的准确性有信心;同样，缺乏准确度的精确测量也是有限的。然而，根据学生的准确性和精确性给他们打分，并不是我们应该仅仅出于传统而做的事情。作为物理科学家，我们有责任为我们的学生和我们自己找到充分的理由，说明我们应该如何、何时以及在多大程度上决定这样做。这篇评论将提供一个框架，使这样的决定，在教育评估领域的文献借鉴。在这样做的过程中，我们将看到与质量保证，方法验证和能力验证中使用的原则和实践的强烈相似之处。
The genesis of this article was a comment from a colleague seeking suggestions for a new experiment, who concluded, BAnd of course we’ll grade on accuracy and precision!^ My immediate reaction was, BWhy ‘of course’?^ I will be completely honest and admit that I too grade my students— at least in part—on accuracy and precision. Indeed, most analytical instructors do the same, to various extents; an informal show of hands at a recent conference revealed that only a small minority did not grade students on accuracy and precision at all. Further, most of us were also graded on accuracy and precision as students. It might therefore seem odd to question this practice, which amounts to a Brite of passage^ for most introductory analytical courses. Yet we subject analytical methods to considerable scrutiny before accepting them as standard practice; should we not do the same for our methods of assessing student performance? Accuracy (closeness of results to the true value) and precision (closeness of results to one another) are arguably the most fundamental concepts and essential skills in chemical analysis: without precision in a set of measurements, it is very hard to be confident about their accuracy; similarly, precise measurements that lack accuracy have limited utility. Grading students on their accuracy and precision, however, is not something we should do simply out of tradition. As physical scientists, we owe it both to our students and to ourselves to have good reasons for how, when, and to what extent we assign such grades should we decide to do so. This review will provide a framework formaking such decisions, drawing on the literature in the field of educational assessment. In its doing so, we will see strong parallels with the principles and practices used in quality assurance, method validation, and proficiency testing.