查询词典 stratified sampling

Methods Students from 6 high schools in Hangzhou were selected by stratified sampling.

中学生的学习成绩是社会、学校、家庭关注的主要问题。

College students were selected as the sample from 182 universities in China according to the principle of stratified sampling.

根据常模组测量的结果，给出了85种生活事件和日常琐事的心理影响指数、心理影响范围和心理影响总量。

Methods Study subjects were selected through stratified sampling and data were collected through questionnaire and physical examination.

方法］采用分层整群抽样的方法获取研究样本，采用问卷调查和体检相结合的方法收集相关信息。

Methods Based on stratified sampling, 363 medical facilities were selected to conduct the survey.

采取分层抽样方法在全国范围内抽取363家医疗机构开展调查。

Methods A self-developed questionnaire was used to investigate 2600 old persons selected in 26 provinces by stratified sampling.

方法在26省按照城乡和男女分层抽样，对2600名老年人进行问卷调查，并对有效的2414份问卷进行数据统计学处理。

In this paper, 236 SMEs of different types of ownership and from different industries are investigated using a stratified sampling method.

本文采用分层抽样方法，对236家不同所有制、具有行业代表性的中小企业展开了问卷调查。

Methods 27 species of Acaroid mites were isolated from 19 grain species in 3 groups of grain stocks with the stratified sampling; Two fuzzy matrixes was founded for classification.

方法从 19种粮食中分离出的粉螨经软划分法建立模糊相似矩阵后，采用直接编网分类和带权重αi 编网分类。

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。

A stratified sampling method is used to estimate the cotton field...

设计了满足生产应用的全国作物面积遥感监测抽样运行方法

Methods a cluster stratified sampling method was used to chose 3 989 pupils from six schools of different levels in xiamen. they were investigated with conners parent symptom questionnaire.

采用整群分层抽样法抽取厦门市6所不同层次的小学一～五年级学生3 989名为调查对象，应用conners量表进行调查，dsm-ⅳ诊断标准确诊。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。