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ANNEX

Content and evaluation criteria of the report on the quality of structural statistics on labour costs and earnings

The reports on quality shall include information on all six dimensions of the European Statistical System (ESS) quality definition, namely relevance, accuracy, timeliness and punctuality, accessibility and clarity, comparability, and coherence.

1.   Relevance

‘Relevance’ denotes the degree to which statistics meet current and potential users' needs. It refers to whether all statistics that are needed are produced and the extent to which concepts used (definitions, classifications, etc.) reflect user needs.

The quality reports on structural statistics on labour costs and earnings respectively shall cover:

The coverage of the items referring to national core users and their main needs, including the provision of information on user satisfaction, is optional.

By way of derogation from Article 2, the optional information on the level of satisfaction with the data offered, if provided, shall be transmitted to Eurostat at the latest 36 months after the end of the reference period.

2.   Accuracy

‘Accuracy’ in the general statistical sense denotes the closeness of computations or estimates to the exact or true values of the variables under consideration.

2.1.   Sampling errors

As an indication of accuracy, the coefficient of variation ( 6 ) shall be calculated and transmitted for key variables of both surveys.

The breakdown by level of education is optional.

In addition, the Member States shall transmit a list of those cells of the multidimensional tables of the publication programme at European level as agreed with the Member States which are deemed not to be sufficiently reliable.

If non-probability sampling is used, a description of the possible sources of imprecision due to the sampling technique used and their effect on the estimations, if available, shall be provided instead.

2.2.   Non-sampling errors

2.2.1.   Coverage errors

The quality reports on structural statistics on labour costs and earnings respectively shall include the following information on coverage:

2.2.2.   Measurement and processing errors

The quality reports on structural statistics on labour costs and earnings respectively shall include the following information on measurement and processing errors ( 12 ):

2.2.3.   Non-response errors

The quality reports on structural statistics on labour costs and earnings respectively shall include the following information on non-response errors:

2.2.4.   Model assumption errors

If modelling is used, the quality reports on structural statistics on labour costs and earnings respectively shall include a description of the models used and an indication of their effects on the estimates (e.g. estimated share of the variable's total), at least for the variables ‘Annual labour costs’ and ‘Gross earnings in the reference month’ respectively as defined in point 2.1.

Particular emphasis shall be given to models for the correction of non-sampling errors such as coverage of units of all requested size classes or NACE sections, imputation or grossing-up to correct for unit non-response.

3.   Punctuality and timeliness

‘Punctuality’ refers to the time lag between the release date of data and the target date when it should have been delivered, for instance with reference to dates announced in official release calendars, laid down by Regulations or previously agreed among partners.

‘Timeliness’ of information reflects the length of time between its availability and the event or phenomenon it describes.

3.1.   Punctuality

In order to understand and to remove problems related to punctuality, information shall be delivered on the process of the survey implementation at national level with a special emphasis on the correspondence between scheduled and actual dates:

3.2.   Timeliness

The quality reports on structural statistics on labour costs and earnings respectively shall contain information on the length of time between the release of data and the reference period of the data at national level.

4.   Accessibility and clarity

‘Accessibility’ refers to the physical conditions in which users can obtain data: where to go, how to get access, delivery time, convenient marketing conditions (copyright, etc.), availability of micro or macro data, various formats and data carriers (paper, files, CD-ROM/DVD, Internet), etc.

‘Clarity’ refers to the degree of comprehensibility, including data information environment, i.e. whether data are accompanied by appropriate metadata, illustrations such as graphs and maps, whether information on their quality is available (including limitations on use) and the extent to which additional assistance is provided.

By way of derogation from Article 2, information on accessibility and clarity shall be transmitted to Eurostat at the latest 36 months after the end of the reference period.

4.1.   Accessibility

The quality reports on structural statistics on labour costs and earnings respectively shall contain the following information on the dissemination modes of the results:

4.2.   Clarity

The quality reports on structural statistics on labour costs and earnings respectively shall contain the following information on the comprehensibility of the results and the availability of metadata:

5.   Comparability

‘Comparability’ aims at measuring the impact of differences in applied statistical concepts and measurement tools/procedures when statistics are compared between geographical areas, non-geographical domains, or over time.

5.1.   Geographical comparability

The quality reports on structural statistics on labour costs and earnings respectively shall contain information on differences between national and European concepts, especially on the definition of statistical units, populations, reference times, classifications and definitions of variables, and their effects on the estimates.

5.2.   Comparability over time

The quality reports on structural statistics on labour costs and earnings respectively shall contain information on changes in definitions, coverage and methods compared with previous surveys, and their effects on the estimates. Information on changes in definitions, coverage and methods, however, is not requested when these changes are the result of amendments to Community legislation.

6.   Coherence

‘Coherence’ of statistics is the extent to which they can be reliably combined in different ways and for various uses. It is, however, generally easier to identify cases of incoherence than to prove coherence.

Sources with similar or even identical variables to structural statistics on earnings and labour costs are the Labour Force Survey (LFS), Structure of Business Statistics (SBS), Labour Cost Index (LCI) and National Accounts (NA). The quality reports on structural statistics on labour costs and earnings respectively shall contain comparisons of data on the following variables from these sources, in total and broken down by NACE sections, and give indications of the reasons if the values differ considerably.