在这个示例中，我们将使用所有方法中最直截了当的一种—将对象引用写入一个文件，该文件将由客户机选取。
In this example, we will use the most straightforward method of all — writing our object reference to a file that will be picked up by our client.
所有规模以上企业都将被选取为调查对象，并上报所有零售网点的数据。
All firms with sales above applicable size cutoffs are selected into the survey with certainty (i. e., probability equal to one) and report for all their retail establishments.
切记，世界上绝大多数统计都不是把所有统计对象问个遍，大部分是选取有代表性的、不能被证明无效的样本。
Moreover, it is important to note that this data collection is in line with normal statistical practice. Most studies are based on typical and effective samples.
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