Labour Force Survey Five-Quarter Longitudinal Dataset, July 2003 - September 2004

<P>Abstract copyright UK Data Service and data collection copyright owner.</P><p><b>Background</b><br>
The <i>Labour Force Survey</i> (LFS) is a unique source of information using international definitions of employment and unemployment and economic inactivity, together with a wide range of related topics such as occupation, training, hours of work and personal characteristics of household members aged 16 years and over. It is used to inform social, economic and employment policy. The LFS was first conducted biennially from 1973-1983. Between 1984 and 1991 the survey was carried out annually and consisted of a quarterly survey conducted throughout the year and a 'boost' survey in the spring quarter (data were then collected seasonally). From 1992 quarterly data were made available, with a quarterly sample size approximately equivalent to that of the previous annual data. The survey then became known as the <i>Quarterly Labour Force Survey</i> (QLFS). From December 1994, data gathering for Northern Ireland moved to a full quarterly cycle to match the rest of the country, so the QLFS then covered the whole of the UK (though some additional annual Northern Ireland LFS datasets are also held at the UK Data Archive). Further information on the background to the QLFS may be found in the documentation.<br>
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<b>Longitudinal data</b><br>
The LFS retains each sample household for five consecutive quarters, with a fifth of the sample replaced each quarter. The main survey was designed to produce cross-sectional data, but the data on each individual have now been linked together to provide longitudinal information. The longitudinal data comprise two types of linked datasets, created using the weighting method to adjust for non-response bias. The two-quarter datasets link data from two consecutive waves, while the five-quarter datasets link across a whole year (for example January 2010 to March 2011 inclusive) and contain data from all five waves. A full series of longitudinal data has been produced, going back to winter 1992. Linking together records to create a longitudinal dimension can, for example, provide information on gross flows over time between different labour force categories (employed, unemployed and economically inactive). This will provide detail about people who have moved between the categories. Also, longitudinal information is useful in monitoring the effects of government policies and can be used to follow the subsequent activities and circumstances of people affected by specific policy initiatives, and to compare them with other groups in the population. There are however methodological problems which could distort the data resulting from this longitudinal linking. The ONS continues to research these issues and advises that the presentation of results should be carefully considered, and warnings should be included with outputs where necessary.<br><br>
<b>LFS Documentation</b><br>
The documentation available from the Archive to accompany LFS datasets largely consists of the latest version of each user guide volume alongside the appropriate questionnaire for the year concerned. However, volumes are updated periodically by ONS, so users are advised to check the latest documents on the ONS <a href="https://www.ons.gov.uk/employmentandlabourmarket/peopleinwork/employmentandemployeetypes/methodologies/labourforcesurveyuserguidance" title="Labour Force Survey - User Guidance" target="_blank">Labour Force Survey - User Guidance</a> pages before commencing analysis. <b>This is especially important for users of older QLFS studies, where information and guidance in the user guide documents may have changed over time.</b><br></p><p><span style="font-weight: bold;">Occupation data for 2021 and 2022 data files</span><br></p><p>The ONS has identified an issue with the collection of some occupational data in 2021 and 2022 data files in a number of their surveys. While they estimate any impacts will be small overall, this will affect the accuracy of the breakdowns of some detailed (four-digit Standard Occupational Classification (SOC)) occupations, and data derived from them. Further information can be found in the ONS article published on 11 July 2023:&nbsp;<a title="Revision of miscoded occupational data in the ONS Labour Force Survey, UK: January 2021 to September 2022" href="https://www.ons.gov.uk/employmentandlabourmarket/peopleinwork/employmentandemployeetypes/articles/revisionofmiscodedoccupationaldataintheonslabourforcesurveyuk/january2021toseptember2022" style="background-color: rgb(255, 255, 255);">Revision of miscoded occupational data in the ONS Labour Force Survey, UK: January 2021 to September 2022</a>.</p><p><span style="font-weight: bold;">2022 Weighting</span></p><p>The population totals used for the latest LFS estimates use projected growth rates from Real Time Information (RTI) data for UK, EU and non-EU populations based on 2021 patterns. The total population used for the LFS therefore does not take into account any changes in migration, birth rates, death rates, and so on since June 2021, and hence levels estimates may be under- or over-estimating the true values and should be used with caution. Estimates of rates will, however, be robust.</p><br>For the second edition (June 2012), a new data file has been deposited, weighted to 2010 population figures. A new version of the longitudinal user guide has been added to the documentation. <br>
<br><br><B>Main Topics</B>:<BR>The five-quarter longitudinal datasets include a subset of the most commonly used variables from the <i>Quarterly Labour Force Survey</i> (QLFS), covering the main areas of the survey.

<P>摘要版权归英国数据服务（UK Data Service）及数据收集版权所有者所有。</P><p><b>背景</b><br>《劳动力调查》（Labour Force Survey，LFS）是一份独特的信息来源，采用就业、失业及经济不活跃的国际定义，涵盖职业、培训、工作时长及16岁及以上家庭成员的个人特征等广泛相关主题。它用于为社会、经济及就业政策提供信息支持。LFS最初于1973-1983年每两年开展一次；1984至1991年间改为年度调查，包含全年季度调查及春季季度的“补充”调查（数据按季节收集）；1992年起开始提供季度数据，季度样本量大致相当于此前的年度数据量，此后该调查更名为《季度劳动力调查》（Quarterly Labour Force Survey，QLFS）。1994年12月起，北爱尔兰的数据收集转为完整的季度周期，以与英国其他地区保持一致，因此QLFS覆盖了整个英国（不过英国数据档案馆也保存了部分额外的北爱尔兰年度LFS数据集）。关于QLFS背景的更多信息可参见文档。<br><br><b>纵向数据</b><br>LFS会连续五个季度保留每个样本家庭，每季度替换五分之一的样本。主要调查旨在生成横截面数据，但目前已将个体记录关联起来以提供纵向信息。纵向数据包含两类关联数据集，采用加权法调整非响应偏差：两季度数据集关联连续两波次的数据；五季度数据集则覆盖一整年（例如2010年1月至2011年3月，含首尾），包含所有五波次的数据。完整的纵向数据系列可追溯至1992年冬季。通过关联记录构建纵向维度，例如可提供不同劳动力类别（就业、失业、经济不活跃）间随时间的总流动信息，这将详细展示在各类别间流动的人群情况。此外，纵向信息有助于监测政府政策的效果，可用于跟踪受特定政策举措影响人群的后续活动及状况，并与人口中的其他群体进行比较。然而，纵向关联过程中存在可能扭曲数据的方法学问题。英国国家统计局（Office for National Statistics，ONS）持续研究这些问题，并建议对结果呈现应谨慎考虑，必要时在输出中加入警示说明。<br><br><b>LFS文档</b><br>档案馆提供的LFS数据集配套文档主要包括各用户指南卷册的最新版本及对应年份的问卷。但英国国家统计局（ONS）会定期更新卷册，因此建议用户在开始分析前，查阅ONS官网《劳动力调查用户指南》页面的最新文档：<a href="https://www.ons.gov.uk/employmentandlabourmarket/peopleinwork/employmentandemployeetypes/methodologies/labourforcesurveyuserguidance" title="Labour Force Survey - User Guidance" target="_blank">劳动力调查 - 用户指南</a>。<b>这对旧版QLFS研究的用户尤为重要，因为用户指南文档中的信息及指导可能随时间发生变化。</b><br></p><p><span style="font-weight: bold;">2021及2022年数据文件中的职业数据</span><br></p><p>英国国家统计局（ONS）发现其多项调查中2021及2022年数据文件的部分职业数据存在收集问题。尽管总体影响估计较小，但这将影响部分详细（四位数标准职业分类（Standard Occupational Classification，SOC））职业的细分准确性及由此衍生的数据。更多信息可参见ONS于2023年7月11日发布的文章：<a title="Revision of miscoded occupational data in the ONS Labour Force Survey, UK: January 2021 to September 2022" href="https://www.ons.gov.uk/employmentandlabourmarket/peopleinwork/employmentandemployeetypes/articles/revisionofmiscodedoccupationaldataintheonslabourforcesurveyuk/january2021toseptember2022" style="background-color: rgb(255, 255, 255);">英国国家统计局劳动力调查中编码错误的职业数据修订：2021年1月至2022年9月</a>。</p><p><span style="font-weight: bold;">2022年加权处理</span></p><p>最新LFS估计所用的人口总数，基于2021年模式，采用实时信息（Real Time Information，RTI）数据对英国、欧盟及非欧盟人口的预测增长率。因此，LFS使用的总人口未考虑2021年6月以来移民、出生率、死亡率等方面的任何变化，故水平估计可能低估或高估真实值，使用时需谨慎。不过，比率估计将保持稳健。</p><br>第二版（2012年6月）新增了一个按2010年人口数据加权的新数据文件，并在文档中添加了新版纵向用户指南。<br><br><B>主要主题</B>:<BR>五季度纵向数据集包含《季度劳动力调查》（QLFS）中最常用变量的子集，覆盖调查的主要领域。