Our analysis shows good intentions in the selection of valid and precise oxygen uptake (ṀO2 ) measurements by retaining only slopes of declining dissolved oxygen level in a respirometer that have very high values of the coefficient of determination, r2 , are not always successful at excluding nonlinear slopes. Much worse, by potentially removing linear slopes that have low r2 only because of a low signal-to-noise ratio, this procedure can overestimate the calculation of standard metabolic rate (SMR) of the fish. To remedy this possibility, we propose simple diagnostic tools to assess the appropriateness of a given minimum acceptable r2 , such as calculating the proportion of rejected ṀO2 determinations, producing a histogram of the r2 values and a plot of r2 as a function of ṀO2 . We offer solutions for cases when many linear slopes have low r2 . The least satisfactory but easiest to implement is lowering the minimum acceptable r2 . More satisfactory solutions involve processing (smoothing) the raw signal of dissolved oxygen as a function of time to improve the signal-to-noise ratio and the r2 s. This article is protected by copyright. All rights reserved.

中文翻译：

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有效的摄氧量测量：善意地使用高 r 2 值可以使标准代谢率的确定偏高

我们的分析表明，通过仅保留呼吸计中溶解氧水平下降的斜率来选择有效和精确的摄氧量 (ṀO2 ) 测量值的良好意图，具有非常高的决定系数 r2 值，并不总是成功地排除非线性连续下坡。更糟糕的是，通过潜在地去除仅由于低信噪比而具有低 r2 的线性斜率，此过程可能会高估鱼的标准代谢率 (SMR) 的计算。为了弥补这种可能性，我们提出了简单的诊断工具来评估给定的最小可接受 r2 的适当性，例如计算被拒绝的 ṀO2 测定的比例，生成 r2 值的直方图和 r2 作为 ṀO2 函数的图。我们为许多线性斜率具有低 r2 的情况提供解决方案。最不令人满意但最容易实现的是降低可接受的最小 r2 。更令人满意的解决方案包括处理（平滑）作为时间函数的溶解氧的原始信号，以提高信噪比和 r2 s。本文受版权保护。版权所有。