分层抽样

Methods A stratified cluster sample of1007college students were questionnaired.

采用分层整群抽样的方法，对广州市1007名大学生进行问卷调查。

Methods A cluster random stratified sample of404medical college students were investigat-ed with a self-administered questionnaire.

采用分层整群抽样方法对404名医学生进行自填问卷调查。

Objective To study the interrelation of life habit,knowledge and consciousness in preventing infectious disease,and to provide evidence for health education of infectious diseases.Methods A stratified cluster sample of1007college students were questionnaired.

目的 了解学生日常生活习惯、传染病防治知识、防治意识的状况及其相互关系，开展大学生传染病防治健康教育提供依据方法采用分层整群抽样的方法，对广州市1007名大学生进行问卷调查。

Methods A stratified random cluster sample of 17269 students in China were investigated with the children and adolescents' QOL scale according to the census data in 2000, and the urban and country norm of the scale were respectively established.

依据2005年第5次全国人口普查资料，在全国进行多阶段分层整群抽样，分别建立城市和农村2套常模。

Methods With stratified clustered sampling method, 375 college students were chosen to complete the questionnaire.

采用分层随机抽样方法，在杭州市的大学中抽取大学生375名进行问卷调查。

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 (1) Randomized stratified clustered sampling method was used.

(1)采用分层整群随机抽样法，收集徐州市

Stratified random sampling was used to recruit 553 participants, and response rate was 70.5%.

取样方式为分层随机抽样，共发出553份，回收390份，回收率70.5%。

The sampling population of this study is girls at five-year, two-year, four-year and two-year technology of a selected college of commerce in Taipei City in stratified random sampling selection with class as sampling unit. A total of 424 girls are included in the formal survey and 405 valid questionnaires collected.

本研究以国立台北市某技术学院在学日间部五专、二专、四技、二技等学制女学生为抽样母群，采分层随机丛集取样方式，以班级为取样单位，正式施测时共抽取424人，有效问卷405份。

Also,it can overcome frequency aliasing effect in general subband coding,and is more flexible than the resolution-layered coding which uses temporal subsampling and spacial filter.

另外，它比采用时间方向亚抽样和空间滤波器的分辨率分层方法更灵活，并克服了频率混叠现象。

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。