Section outline

  • General

    Collapse all Expand all

  • 创建代表样本

    Convincing Concussions
    ::说服力冲击

    An important issue currently facing every sport is concussions. Over the past decade, our understanding of brain trauma has grown significantly along with our ability to diagnose concussions. Sports are trying everything from rule changes to new equipment to minimize the number of concussions. However, sports leagues need to test these rule changes and new equipment designs to ensure player safety. This process requires sampling.
    ::目前,每一项运动都面临一个重要问题就是脑震荡。 在过去的十年中,我们对脑创伤的理解随着我们脑震荡的诊断能力而大大提高。 体育正在尝试从规则改变到新设备的一切,以尽量减少脑震荡的数量。 然而,体育联盟需要测试这些规则改变和新设备设计以确保玩家安全。 这一过程需要抽样。

    Discussion Question
    ::讨论问题

    Sanaya is a neurologist who is collecting data on concussions from a sample of players from the National Football League, what factors should she consider when picking players for her sample? 
    ::Sanaya是一个神经学家,他正在收集来自全国足球联盟的选手的脑震荡数据,她在挑选选手时应考虑哪些因素?

    The table below displays data taken from a 6-year period in the NFL from 2002 and 2007. 
    ::下表列示了2002年和2007年从全国妇联6年期中得出的数据。

    Position Concussions Percentage
    Quarterback 48 6.3
    Wide Receiver 73 9.6
    Tight End 58 7.7
    Running Back 69 9.1
    Offensive Line 56 7.4
    Secondary 148 19.5
    Linebacker 73 9.6
    Defensive Line 42 5.5

    Discussion Question
    ::讨论问题

    Why do you think the concussion rates for each position are different?
    ::为什么你认为每个位置的脑震荡率不同?

    What is Random? 
    ::什么是随机?

    In the example above, where Sanaya is collecting from players from the National Football League, there are many factors to consider to ensure a representative sample . For example, if she only chooses quarterbacks, her sample would only have data that relates to the specific things that a quarterback does during a game. What Sanaya need s to do is  take a sample of randomly chosen players.
    ::在以上的例子中,Sanaya正在从全国足球联盟的球员那里收集到许多因素,以确保具有代表性的样本。 比如,如果她只选择了四分卫,那么她的样本将只有与四分卫在比赛中所做的具体事情相关的数据。 Sanaya需要做的是抽取随机挑选的球员的样本。

    In a classroom, if a teacher wants to choose a random group of students he or she might pull names from a hat. However, what should the person choosing the group do if the population is 1,000 people? One approach is to do a raffle where every person is given a number and specific numbers are physically chosen from a container at random. Another approach is to use technology to generate  approximately random choices. Computers use complex algorithms to generate numbers which are essentially random. These numbers can be assigned to individuals, usernames, email addresses, or other lists.
    ::在课堂上,如果教师想选择随机的学生群体,他或她可以从帽子上取出名字。然而,如果人口为1,000人,选择该群体的人应该怎么做? 一种办法是进行抽奖,在抽奖时给每个人一个数字,从一个容器中实际抽取具体数字。另一种办法是使用技术来产生大致随机的选择。计算机使用复杂的算法来产生基本上随机的数字。这些数字可以分配给个人、用户名、电子邮件地址或其他名单。

    Example
    ::示例示例示例示例

    You run a business and every month you extend a special offer to a randomly chosen 20% of your customers. One way to go about doing this might be to choose people from a mailing list or list of usernames from an app. You could assign every customer a number between 1 and the number of customers. You could then extend the offer to every coupon to a customer who was assigned a multiple of 5, representing 20%.
    ::您经营一个企业,每个月您都会向随机选择的20%客户提供特别报价。 这样做的一个方法可能是从邮件列表或应用程序用户名列表中选择人。 您可以将每个客户的号码从1到客户数量之间分配。 然后您可以将报价扩大到每个优惠券, 给一个被指定5倍的客户, 代表20%的客户。

    Discussion Question
    ::讨论问题

    How could you do this in a way that every customer is extended the offer once before any repeats?
    ::你怎么能这样做呢? 让每个顾客在重复之前 一次得到延期?

     

    Randomization
    ::随机化

    The process of selecting a sample from randomly chosen members of the population is called randomization . Choosing a sample randomly from the population minimizes the effects of bias on the results.
    ::从随机选择的人口成员中选择样本的过程称为随机化,随机从人群中选择样本可以最大限度地减少偏见对结果的影响。

    Use the interactive below to identify which sample is random.
    ::使用下面的交互数据来识别哪个样本是随机的。

    Choosing the Best Sample
    ::选择最佳样本

    Now that you know how to choose a good sample based on sample size and randomization of participants, it’s your turn to choose the sample. State the population, appropriate size, and data collection method for the following sample sizes:
    ::现在,你知道如何根据抽样规模和参与者随机化选择好的样本,现在轮到你选择样本了。 说明以下样本大小的人口、适当规模和数据收集方法:

    1. You want to determine the most popular video games the students in your school are playing.
      ::您想决定您学校里学生玩的最受欢迎的电子游戏。请访问InfoFinland上的 电子游戏。
    2. You want to determine what the most popular holiday presents are for children in your state.
      ::你想决定什么是最流行的节日礼物 儿童在你的状态。
    3. You want to determine the percentage of otters in Alaska that are female.
      ::您想要确定阿拉斯加的水燕中女性的比例 。
    4. You want to determine what people all over the world think of a product.
      ::你想决定全世界人们对产品的看法
      Summary
    • Randomization is the process of selecting a sample from randomly chosen members of a population.
      ::随机选取是从随机选定的人口成员中挑选样本的过程。
    • Randomization helps prevent different types of sampling bias. Minimizing bias will help make samples more representative of their corresponding populations.
      ::随机化有助于防止不同类型的取样偏差,尽量减少偏差有助于使样品更能代表相应的人口。