The percent deviation formula is very useful in determining how accurate the data collected by student teams is. In this case the data is usually compared either to a standard prepared by the instructor or by a quality control lab (like the City of Gresham or United Sewage Agency).Note that a team can be very precise in their measurements and have a high coefficient of variance for a set of data (say 96%) which is highly desirable, and still they may not have accurate test results. This means that they repeatedly made the same mistake in collecting data. The team would have to create a graph comparing the sampled data to the quality control data or they could calculate percent deviation using the following equation: Percent deviation = (student data - lab data) / lab data then multiplied by 100.orPercent deviation = (student data - QC data) / QC data then multiplied by 100.

若能收集到该词条相关资料的跟帖者给予奖励，根据收集资料的水平给予5～100不等的论坛币，当然也可以谈谈自己的看法、应用背景，相关软件知识，上传资料等等都可以。请大家尽量不要复制一些搜索引擎很容易收集到的资料。

     我每天都会发送不等数量的词条，所以诚邀不同统计背景的各路大侠给予评论。

     欢迎大家多多跟帖！要数量也要质量哟