Labour Force Sample Survey 1991-92 panel file, 2.q.1991-3.q.1992

Labour Force Sample Survey 1991-92 panel file, 2.q.1991-3.q.1992
As of the 1st quarter of 1972, SSB has conducted official quarterly labour force surveys (AKU). These surveys aim to give the labour force authorities (and other people interested) knowledge of the occupational structure of the population and how it develops over time. The surveys are meant to give a foundation and statistical material for occupational prognoses and labour research. The samples in AKU are from 1992 representative at county level. In the period 1972-1991 they were representative on county pair level.
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Originally, AKU respondents were interviewed in two consecutive quarters of a year, followed by a pause of two quarters, and then another two quarters of interviews. The sample was approximately 10-11.000 respondents in each quarter up until 1988. Originally, AKU was intended to be an analytical supplement to the monthly occupational statistics that was based on the social security membership index file. However, the social security-based statistics disappeared when the sickness benefit was included in the National Insurance as of 1st of January 1971, and AKU has after gradually developed into the most significant source of knowledge of the state of the labour market and its development.

In 1975, Statistics Norway changed the sampling frame of survey research, see article 37: “Om bruk av stikkprøver ved kontoret for intervjuundersøkelser”, SSB (About the Use of Random Samples at the Office for Survey Research, Statistics Norway) by Steinar Tamsfoss, and SØS 33: “Prinsipper og metoder for Statistisk sentralbyrås utvalgsundersøkelse (Principles and Methods for Statistics Norway's sample research) by Ib Thomsen. Simultaneously, the method for estimation of inflation to national numbers was changed, so that reasonable numbers for regions do exist from 1975 and onwards. The change in 1975 led to a different way of interviewing in groups. This caused amongst other things a break with the AKU panel systematics.

In the AKU survey of 1976, a slightly changed questionnaire was introduced. Also, there was a return to the original 6-quarter rotation scheme. The new questionnaire implied a better identification of family workers and persons that are temporarily without paid work. Thus, 30-35 000 more people were defined as employed. The group of "job-seekers without income" were also extended to include persons that were on an involuntary leave of absence. The questions concerning underemployment and “over employment” in the original questionnaire were abandoned.

From the 1st quarter of 1987, the estimation method (inflation to national numbers) was slightly changed. There was also a minor adjustment in the definition of employment. In order to ensure that the numbers were to be comparable to earlier surveys, new versions of the 1980-1986 AKU-files were drawn up. Consequently two versions of the 1980-1987 files - respectively with the old and new methods of estimation - exist. The “old” means that the data are comparable to the original numbers published in the period of 1972 - 1987, whilst the “new” implies that the data are comparable to numbers published after 1987.
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Between the 1st and 2nd quarter of 1988, the AKU file description was changed. The variable “Labour-market status” was given a different coding. In addition, adjustments in the data collections were made - from interviewing a specific week every quarter to carry out continuous weekly interviews. SSB also started up an escalation scheme to increase the sample size. This affected the weights, and from the 2nd quarter of 1988, these were recalculated monthly. To balance out the quarterly or yearly files to total national numbers, the monthly weights therefore had to be divided in three or twelve to give the correct total number.

In 1996, AKU was significantly revised: The questionnaire, the file description and the standard for coding of industry and occupation. The data collection also changed to CATI - Computer Assisted Telephone Interviewing. A new classification of industry was put into use (NOS C 182, based on the EU standard NACE, Rev.1). This standard was updated in 2002 and 2007. Also, the new occupational classification (STYRK) based on ISCO 88 was used from 1996 and onwards. The variable indicating socio-economic status was omitted, as a similar variable was not developed in the new occupational classification.

As from January 2006 some major changes were introduced to AKU in order to enhance its comparability to similar surveys in other countries. The changes consist of minor definitional adjustments of unemployment, some adjustments and enlargement of the questionnaire and a change in age definition (age at reference point instead of at the end of the year). Simultaneously the lower age limit to be included in AKU was lowered from 16 to 15 years. This led to some breaks in the time series in the mentioned areas.

1991-1992年劳动力抽样调查面板数据集（1991年第2季度至1992年第3季度）
自1972年第1季度起，挪威中央统计局（Statistisk sentralbyrå, SSB）便开展了官方季度劳动力抽样调查（AKU）。此类调查旨在为劳动力管理部门及其他相关方提供人口职业结构及其随时间演变的相关信息，为职业预测与劳动力研究提供基础数据与统计资料。1992年起，AKU的样本在县级层面具有代表性；1972-1991年期间，样本则在县域配对层面具有代表性。
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最初，AKU的受访对象需在一年中的两个连续季度接受访谈，随后暂停两个季度，再开展后续两个季度的访谈。1988年之前，每季度的受访样本量约为10000至11000人。AKU最初旨在作为基于社会保障参保索引文件的月度职业统计的分析补充，但1971年1月1日病假福利纳入国民保险体系后，基于社会保障的统计数据不复存在，AKU也逐渐演变为了解劳动力市场现状及其发展态势的核心信息来源。

1975年，挪威中央统计局调整了调查研究的抽样框架，相关细节可参考Steinar Tamsfoss撰写的SSB第37号文章《关于调查研究办公室的随机抽样应用》，以及Ib Thomsen撰写的SØS 33号文件《挪威中央统计局抽样调查的原则与方法》。与此同时，全国层面的通胀估算方法也进行了调整，自此1975年起，区域层面的合理估算数据得以生成。1975年的此次变革带来了群体访谈方式的调整，其中一项直接后果便是打破了AKU的面板调查系统规则。

1976年的AKU调查启用了略微修订的问卷，并重新采用了最初的6季度轮换方案。新版问卷可更精准地识别家庭帮工与临时无薪劳动者，因此被界定为“就业”的人群增加了3万至3.5万人。“无收入求职者”群体的覆盖范围也扩展至非自愿休假人员，原版问卷中关于就业不足与“过度就业”的相关问题则被移除。

自1987年第1季度起，全国层面的通胀估算方法进行了小幅调整，就业的定义也进行了小幅修订。为确保数据与此前调查的可比性，研究人员编制了1980-1986年AKU数据集的新版文件，因此1980-1987年的数据集存在两个版本，分别采用旧版与新版估算方法。“旧版”意味着数据可与1972-1987年发布的原始数据进行比对，而“新版”则代表数据可与1987年之后发布的数据进行比对。
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1988年第1季度至第2季度期间，AKU数据集的字段说明进行了修订，"劳动力市场状态"变量的编码规则进行了调整。此外，数据收集方式也进行了调整：从每季度固定一周开展访谈，改为持续进行每周访谈。挪威中央统计局还启动了样本量扩容计划，这一调整对样本权重产生了影响，自1988年第2季度起，样本权重改为每月重新计算。为使季度或年度数据集与全国总数据保持一致，需将月度权重除以3或12，以得到正确的总权重。

1996年，AKU进行了重大修订，涉及问卷、数据集字段说明以及行业与职业编码标准。数据收集方式也改为计算机辅助电话访谈（Computer Assisted Telephone Interviewing, CATI）。新版行业分类标准（基于欧盟NACE Rev.1标准的NOS C 182分类）正式启用，该标准分别于2002年与2007年进行了更新。自1996年起，基于国际标准职业分类88版（International Standard Classification of Occupations 88, ISCO 88）的新版职业分类（STYRK）开始投入使用。由于新版职业分类未设置对应的社会经济地位变量，原有的社会经济地位标识变量被移除。

自2006年1月起，AKU进行了多项重大调整，以提升其与其他国家同类调查的可比性。调整内容包括对失业定义的小幅修订、问卷内容的调整与扩充，以及年龄定义的变更（以基准时点年龄替代年末年龄）。与此同时，AKU的受访年龄下限从16岁下调至15岁，上述调整导致上述领域的时间序列出现了断点。