查询词典 random-mating population

First, this paper gives an introduction of some methods of unequal probability sampling, their estimators and variance estimators, including sampling with pps with replacement, methods of sampling without replacement suggested by Brewer, Durbin, Sampford , Des Raj , Murthy , Rao-Hartley-Cochran.Then, at the basis of Rao and Baylesss study , we consider that population can be splited two random subpopulations, which are respectively drawn from different infinite super-populations, and compare the stabilities of estimators of the methods that given above.

本文首先从理论上介绍了若干种不等概率抽样方法，它们的估计量、估计量的方差及其估计，其中包括有放回PPZ及PPS抽样，不放回不等概率抽样中的Brewer、Durbin、Sampford、Des Raj，Murthy、Rao-Hartley-Cochran等人的方法；其次，在Rao和Bayless两人就样本单元数n=2的情形对上述抽样方法进行比较的基础上，将总体随机地分成两个子总体，视每个子总体取自不同的线性超总体，在文中，我们利用计算机实现随机分组，并通过画图比较各方法估计量的稳定性，结果表明，对变异系数C.V。

Stratified sampling design is applied in obtaining an accurate representation of the population by grouping the data into nonoverlapping groups, for example gender or income level, then selecting a simple random sample within each group.

分层抽样是将总体分成若干个组分，在每个组分中进行简单随机抽样，其原则在于将类似的样本归在一个组里面。

The population was 624 certificated special education teachers of elementary school in Kaohsiung city and Kaohsiung County, drawing 250 subjects by stratified random sampling for pretesting.

本研究主要探讨高雄县市国小特殊教育教师之教师信念、生命意义感与生命教育态度的关系。

The regression period of cotton aphid: The spatial patterns of aphid population were confirmed to exponent, linear and nugget model under large scale along with the time sequence, respectively, results suggested that the spatial patterns were aggregated, medium intensity aggregation and random distribution, respectively, and the space continuity is decreasing.

3消退期：大尺度下按时间顺序，棉蚜的变异函数模型分别为指数型、线性及块金模型，表明空间格局分别表现为聚集型、中等强度和随机分布，棉蚜种群的空间自相关性及空间连续性在后期递减。

We will study the properties of the distributions of OLS estimators over different random samples from the population.

通过从总体中抽取的不同的随机样本，我们将研究这些OLS估计量的分布。

We will study the properties of the distributions of OLS estimators over different random samples from the population.

从总体中抽取的不同的随机样本可得到不同的OLS估计量，我们将研究这些OLS估计量的分布。

After the Second World War, along with major cities in the United States population growth, the form of random street basketball more and more people have also been accepted and welcomed.

在第二次世界大战之后，伴随着美国主要城市的人口剧增，形式随意的街头篮球也受到越来越多人的接受和欢迎。

B chromosomes do not pair with A chromosomes,they are inherited in a non-Mendelian way, exhibiting meiotic and mitotic instability andnondisjunction. Bs have little influence with the phenotype. DNA sequence differences in rye genomes (JNK population with similar geneticbackground) with and without B chromosomes were analyzed by random amplifiedpolymorphic DNA.

目前，已在约1300种植物和逾500种动物中发现了B染色体，实际含有B染色体的物种数远远不止这些。B染色体具有许多独特的性质：它独立于A染色体之外，不与任何A染色体配对，为非孟德尔遗传，具有不分离机制，不携带或极少携带核仁组织区，无影响表型的基因。

The emergence and population dynamics of M. aquaticum in transplanted rape fields was studied by survey of permanent quadrats and random quadrats, and field trials for herbicide screening were further conducted to develop the control strategy.

采用固定样方和随机样方法研究了移栽油菜田牛繁缕的出苗规律及在田间的种群动态，结合除草剂筛选进一步探讨了其控制策略。

Population in Donghu Lake was consisted of random distributed clonal groups, which had large genetic differentiations.

因此不同的基因型得以在不同的湖区随机分布。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。