And statistical controls are unlikely to compensate for a poor sampling strategy that does not yield a sample representative of the population to which we want to generalize.
一个差劲的采样策略并不能产生一个我们需要的代表总体的样本，而统计管理不太可能弥补这一点。
Although random sampling used for many surveys fails to cover large segments of the population, the procedure nonetheless offers insight into voting and consumption patterns.
虽然许多调查所用的随机取样不能覆盖大部分人口，但是这一过程使人们能更深刻地理解选举和消费的模式。
Any discrepancies between the observed and expected frequencies can be accounted for as expected sampling variability from the same population of Nova Scotia beer drinkers.
观察频率和期望频率之间的任何差异都可以解释为新斯科舍省相同啤酒消费者的期望抽样可变性。
Methods Subjects were collected from community population by stratified multi-stage cluster sampling method. The data gathered from case investigation and serological detection.
方法对社区人群采用多阶段分层整群随机抽样方法抽取研究对象，进行个案调查和血清学检测。
Methods With simple random sampling, 1010 floating population and 240 local people in Wuxi were interviewed by questionnaire.
方法采用单纯随机抽样方法，对无锡市1010名流动人口和240名当地人群进行问卷调查。
The model data conversion, the population sequential sampling and the theoretical sampling number model were also built up in the paper.
在分布型研究基础上，探讨了资料代换模型，最适抽样数和种群序贯抽样模型。
The involves the methods of design study, target population, sampling method and the techniques that were used to select the sample size.
涉及到设计方法的研究中，需要根据目标人群，抽样方法和技术来选择样本大小。
Under population follow normal distribution hypothesis, designing combine median-range adaptive control charts with variable sampling interval, variable sample size and variable control limit .
在假设总体服从正态分布的条件下，设计了抽样区间，样本容量和控制限都变化的全变化参数的中位值-极差联合控制图。
Under simple random sampling scheme without replacement and unknown proportion of population possessing neutral attribute, the optimal allocation of sizes of two sub-samples is given.
对简单随机不放回抽样，在总体非敏感属性个体比例未知的情况下，给出了两个子样本容量的最优配置。
The national total population was adjusted for the sampling error and investigation error.
全国数据根据抽样误差和调查误差进行了修正。
The distribution and quantity of Felis lynx population in the northeast have been found out by the three-stage sampling method.
我们利用三阶抽样法，查清了东北地区猞猁种群的分布及数量情况。
A kind of nonlinear regression estimator for limited Population is given and the quality and the sampling variance about is discussed.
对有限总体在不放回抽样的方法下，构造了一类非线性回归估计量，讨论了它的性质及其有关抽样误差．。
Chapter 2 describes the basic situation of Changshu floating population by using large amounts of sampling survey materials, and grasps their principal character accurately.
第二章充分利用抽样调查等第一手资料，详细描述了常熟流动人口的基本情况，比较准确地把握了常熟流动人口的现状特征。
To undertake a systematic random sampling, one needs to know the total number of households, the average number of children under 5 years of age in a household, and the total population.
要进行一次系统随机抽样，必需知道人群中的家庭总数，平均每户家庭5岁以下儿童的个数，以及总人口。
We give the approximation formulas of the variance of the sample ratio estimator for a population mean and its asymptotically non-biased estimator in multi-stage sampling.
讨论多阶段抽样比率估计及其样本量选择的问题，给出了比率估计抽样均方误差的近似公式及其渐近无偏估计的公式。
We give the approximation formulas of the variance of the sample ratio estimator for a population mean and its asymptotically non-biased estimator in multi-stage sampling.
讨论多阶段抽样比率估计及其样本量选择的问题，给出了比率估计抽样均方误差的近似公式及其渐近无偏估计的公式。
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