Archaeologists see the value, if not the allure, of formation theory. Before inferring what happened in the past and why, we must know how the material record formed. Pottery is abundant and informative, therefore a common analytical subject. Understanding size and composition of ceramics assemblages requires formation theory, including knowledge of vessel use life. This fundamental quantity has two salient properties. The first—central tendency measured by mean or median—is widely acknowledged. Use life's second, equally important, property is the distribution of failure-age by specimen across assemblages. This article considers how and why both use-life properties affect size and composition of pottery assemblages. From a longitudinal ethnoarchaeology of household pottery in Michoacán, Mexico, it identifies vessel-size measures that correlate with use-life mean, and it demonstrates archaeologically innovative ways to characterize distributions that improve both analysis of assemblages and comparison between them.

考古学家看到了形成理论的价值，如果不是魅力的话。在推断过去发生的事情和原因之前，我们必须知道材料记录是如何形成的。陶器内容丰富且内容丰富，因此是一个常见的分析主题。了解陶瓷组合的尺寸和成分需要形成理论，包括容器使用寿命的知识。这个基本量有两个显着的特性。第一个——以平均值或中位数衡量的集中趋势——被广泛认可。使用寿命的第二个同样重要的属性是不同组合中的试样的失效年龄分布。本文考虑了这两种使用寿命特性如何以及为什么会影响陶器组合的尺寸和成分。来自墨西哥米却肯州家用陶器的纵向民族考古学，