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数据质量

Data Quality
课程网址: http://videolectures.net/ida07_lenz_dq/  
主讲教师: Hans-Joachim Lenz
开课单位: 自由大学
开课时间: 2007-10-05
课程语种: 英语
中文简介:
在工业中,在产品和后期服务的“质量控制或保证”的背景下使用的术语“质量”具有大约一百年的历史。它在ISO标准中用作“相对于给定使用目标的适用性”。查看“产品”和“流程”,可以区分“设计质量”和“性能质量”。 “数据质量”这一术语大约在同一时间用于统计局和超国家组织(经合组织,联合国NAGroup等)。二十年前,当检测到与数据仓库,ETL,数据清理,数据挖掘和数据集成相关的数据质量问题时,它在计算机科学中变得流行起来。数据质量主要定义如上,即给定在特定域上进行数据处理的目标的适用性。例如,目标可以是网络挖掘,其中要集成半结构化数据。显然,术语“数据质量”有许多不同的方面。逐步细化从几个数据源开始的粒度到属性(变量)的单个值,可以在多个源或数据库,单个数据库(在模式或数据级别上),记录和值之间有所不同。例如,在数据级错误,异常值,空值(缺失值),不一致(不连贯)值或简单地语义滥用数据是关注的,而在模式级别上可能违反完整性约束。所有这些因素都可能导致数据质量低下。
课程简介: In industry the term „Quality“ used in the context of “Quality Control or Assurance” of products - and later services - has a history of about one hundred years. It is used in an ISO norm as “Suitability for use relative to a given objective of usage”. Looking at “Products” and “Processes” one distinguishes between “Quality of Design” and “Quality of Performance”. “Data Quality” is a term which is used at Statistical Offices and supranational Organizations (OECD, UN NAGroup etc.) for about the same time. It became popular in computer science twenty years ago, when data quality problems related to data warehousing, ETL, data cleansing , data mining and data integration were detected. Data Quality is mostly defined as above, i.e. fitness for use given an objective of data processing on a specific domain. For example, the objective may be web-mining where semi-structured data is to be integrated. Evidently, the term “data quality” has many various facets. Stepwise refining the granularity starting from several data sources to a single value of an attribute (variable) one can differ between multi-sources or data bases, single databases (on the schema or data level), records and values. For instance, on the data level errors, outliers, null-values (missing values), inconsistent (incoherent) values or simply semantic misuse of data are of concern while on the schema level integrity constraints may be violated. All these factors may lead to low data quality.
关 键 词: 后期服务; 数据挖掘; 数据集成
课程来源: 视频讲座网
最后编审: 2019-04-27:cwx
阅读次数: 68