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  • General

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  • 准确性和准确性

    Person preparing to hit a golf ball on a green field towards a hole.

    Have you ever played golf, like the person  in this photo? Even if you haven’t played golf before, you probably know that the goal of the game is to hit the ball into a hole with the fewest strokes of the club. Golf is a good way to understand two important concepts in scientific measurement: accuracy and precision .
    ::你曾经打过高尔夫球吗,就像这张照片中的人? 即使你以前没有打过高尔夫球,你也可能知道这场比赛的目标是用俱乐部中最少的球击入一个洞里。 高尔夫球是理解科学计量中两个重要概念 — — 精确度和精确度 — — 的好方法。

    Accuracy
    ::准确性

    The accuracy of a measurement is how close the measurement is to the true value. If you were to hit four different golf balls toward an over-sized hole, all of them might land in the hole. These shots would all be accurate because they all landed in the hole. This is illustrated in the sketch below.
    ::测量的准确度是测量的精确度有多接近真实值。 如果您要打四个不同的高尔夫球到一个超大洞, 所有的高尔夫球都可能会降落在洞里。 这些镜头都是准确的, 因为它们都降落在洞里。 下面的草图说明了这一点 。

    A sketch showing a flag in an oversized hole with balls clustered around it, illustrating accuracy.

    Precision
    ::精精度

    As you can see from the sketch above, the four golf balls did not land as close to one another as they could have. Each one landed in a different part of the hole. Therefore, these shots are not very precise. The precision of measurements is how close they are to each other. If you make the same measurement twice, the answers are precise if they are the same or at least very close to one another. The golf balls in the sketch below landed quite close together in a cluster, so they would be considered precise. However, they are all far from the hole, so they are not accurate.
    ::从上面的草图中可以看到,四个高尔夫球没有像它们那样相近地降落。每个高尔夫球都降落在洞的另一部分。 因此, 这些射击并不十分精确。 测量的精确度是它们彼此之间的距离。 如果您做两次同样的测量, 答案是准确的, 如果它们相同, 或者至少非常接近。 下面的草图中的高尔夫球在一组球群中非常接近地降落在一起, 所以它们会被认为是精确的。 但是, 它们都离洞很远, 所以它们不准确 。

    A golf hole with a flag and four golf balls clustered nearby.

    Q: If you were to hit four golf balls toward a hole and your shots were both accurate and precise, where would the balls land?
    ::问:如果你把四个高尔夫球打向一个洞, 你的射击既准确又精确, 球会落到哪里?

    A: All four golf balls would land in the hole (accurate) and also very close to one another (precise).
    ::A:所有四个高尔夫球都会降落在洞里(准确),

    Summary
    ::摘要

    • Accuracy means making measurements that are close to the true value.
      ::准确性是指进行接近真实值的测量。
    • Precision means making measurements that are close in value to each other but not necessarily close to the true value.
      ::精确度意味着进行彼此接近但不一定接近真实值的测量。

    Review
    ::回顾

    1. Complete this statement: A measurement is accurate when it is __________.
      ::完成本说明:当计量为_______时,计量是准确的。
    2. What makes two measurements precise?
      ::是什么使两种测量精确?
    3. Kami measured the volume of a liquid three times and got these results: 66.71 mL, 66.70 mL, 66.69 mL. The actual volume of the liquid is 69.70 mL. Are Kami’s measurements precise? Are they accurate? Explain your answers.
      ::卡米三次测量液体的体积,结果如下:66.71毫升、66.70毫升、66.69毫升。 液体的实际体积是69.70毫升。卡米的测量精确吗?它们准确吗?请解释一下答案。

    Resources
    ::资源