The European Statistical System (ESS), in its efforts to continuously improve the quality of its products and services, has adopted a general definition of quality as ‘the totality of features and characteristics of a product or service that bear on its ability to satisfy stated or implied needs’. In order to make this definition operational, six dimensions have been identified which make up the quality of statistical products and services:
relevance;
accuracy;
timeliness and punctuality;
accessibility and clarity;
comparability;
coherence.
Quality reports are an appropriate tool to collect information on the quality of different products and services in a harmonised way. They shall include information on all six dimensions of the ESS quality definition, as well as a general overview of the national data collection on job vacancies. The information shall be presented according to the following structure:
A general description shall include the following elements, where appropriate:
Identification of the source of the data,
Coverage (geographical, NACE, enterprise size),
Reference dates,
Periodicity of national publication,
Definition of the statistical unit.
Base used for the sample,
Sampling design,
Retention/renewal of sampling units,
Sample size,
Stratification.
Brief description of the weighting method,
Weighting dimensions.
Brief description of the data collection method(s).
Brief description of the source(s) including:
Maintenance agency,
Updating frequency,
Rules for clearance (of outdated information),
Voluntary/compulsory reporting and sanctions.
Brief description of when data have to be deleted for reasons of confidentiality.
Brief description of seasonal adjustment procedures, in particular with regard to the European Statistical System guidelines on seasonal adjustment which have been endorsed and supported by the SPC.
‘Relevance’ refers to whether all statistics that are needed are produced and the extent to which the concepts used (definitions, classifications etc.) reflect user needs.
The quality report shall include
a description of missing variables and missing breakdowns of the variables,
a progress report on the implementation measures regarding quarterly job vacancies statistics of Regulation (EC) No 453/2008, together with a detailed plan and timetable for completing implementation, and a summary of the remaining deviations from EU concepts.
In addition, it may include
a summary comprising a description of the national users, their main needs and the extent to which their needs are satisfied.
‘Accuracy’, in the general statistical sense, refers to the closeness of estimates to the unknown true values of the variable under consideration.
As an indication of accuracy, the coefficient of variation taking into account the sampling design shall be calculated and transmitted for the number of job vacancies for the latest version of the NACE at section level and broken down by size classes (1-9/10 + employees).
If the coefficient of variation cannot be calculated, the estimated sampling error in terms of the absolute number of vacant posts shall be provided instead.
The quality reports shall include the following information on coverage, where appropriate:
A table showing the number of business units of the sample and the percentage of the business units represented in the sample(s)/register(s), broken down by size class (strata),
Description of any difference between the reference population and the study population,
Description of classification errors,
Description of any difference between the reference dates and the reference quarter,
Any other relevant information.
N.B.: Where individual administrative data are used, a similar analysis shall be provided, based on the administrative reference file, including reporting and deregistration errors.
The quality reports shall include
Information on variables with non-negligible measurement and processing errors,
Information on main sources of (non-negligible) measurement and processing errors and, if available, on methods applied for correction.
The quality reports shall include the following information on non-response errors, where appropriate:
Unit response rate,
Item imputation rate and methods and, where possible, the effect of imputation on the estimates for the variables transmitted.
N.B.: Where individual administrative data are used, non-availability of the administrative record or item replaces non-response.
If modelling is used, the quality reports shall include a description of the models used. Particular emphasis should be given to models for the correction of non-sampling errors, such as coverage of units of all requested size classes or NACE breakdowns, imputation or grossing-up to correct for unit non-response.
N.B.: Where individual administrative data are used, there shall be comments on the correspondence between the administrative concepts and the theoretical statistical concepts. Any changes in national legislation that lead to changes in definitions applied and, where possible, the impact on the results shall be reported.
Member States may provide a revision history, including the revisions in the published number of job vacancies and a summary of the reasons for the revisions.
An assessment of the non-sampling errors, in terms of the absolute number of vacant posts, shall be transmitted for the total number of job vacancies and, where possible, for aggregation level of NACE Rev. 2 specified in Annex 1 to this Regulation and size classes (1-9, 10 + employees).
‘Timeliness’ of information reflects the length of time between its availability and the event or phenomenon it describes.
The quality reports should contain information on the time span between the release of data at national level and the reference period of the data.
‘Punctuality’ refers to the time lag between the release date of data and the target date when the data should have been delivered, for instance with reference to dates announced in official release calendars, laid down by Regulations or previously agreed among partners.
In order to understand and to remove problems related to punctuality, information on the process of survey implementation at national level for the last four quarters should be delivered, with a special emphasis on the correspondence between scheduled and actual dates:
Deadlines for the respondents to reply, also covering recalls and follow-ups,
Period of the fieldwork,
Period of data processing,
Dates of publication of first results.
‘Accessibility’ refers to the physical condition in which users can obtain data on the following: 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.
The quality reports should contain the following information on the methods of disseminating the results:
Dissemination scheme, including to whom the results are sent,
References for publications of core results, including those with commentary in the form of text, graphs, maps, etc.,
Information on what results, if any, are sent to reporting units included in the sample.
‘Clarity’ refers to the degree of comprehensibility, including information about the 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 limitation on use) and the extent to which additional assistance is provided.
The quality reports should contain the following information on the comprehensibility of the results and the availability of metadata:
Description of and references for metadata provided,
References for core methodological documents relating to the statistics provided,
Description of main actions carried out by the national statistical services to inform users about the data.
The quality reports shall contain information on differences between national and European concepts, and — to the extent possible — their effects on the estimation.
The quality reports shall contain information on changes in definitions, coverage and methods in any two consecutive quarters, and their effects on the estimation.
‘Coherence’ of statistics refers to their adequacy to be reliably combined in different ways and for various uses. However, it is generally easier to show cases of incoherence than to prove coherence.
The quality reports shall contain comparisons of data on the number of vacant jobs from other relevant sources when available, in total and broken down by NACE at section level when relevant, and shall indicate the reasons if the values differ considerably.
The first quality report shall also include the following items for the back data:
Description of the sources used for the back data and the methodology employed,
Description of any differences between the coverage (economic activities, employees, variables) of the back data and that of the current data,
Description of the comparability of the back data and the current data.