在5个城市作整群分层随机抽样调查确定与事故倾性有关指标的正常值范围。
The normal value range of indicators about accident proneness were detected according to epidemiological survey results using stratified random cluster sampling in 5 cities.
本文引入了基于日内价格幅度与回报两个测度指标的随机波动率模型。
In this paper we propose to a stochastic volatility model based on daily returns and intra-daily high-low price range jointly.
方法采用随机抽样方法，随机抽取市场上销售的食用槟榔，按DB43/132-2004中方法进行理化与微生物指标的检测。
Method Random sampling was used to edible areca-nut sold on market, followed by series of physicochemical and microbiological examination on DB43/132-2004 standard.
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