Error correction and data revision at STATEC

This document first describes STATEC’s procedures to detect, correct and notify errors that may occur during the collection, processing and dissemination of statistical data. It then provides explanations on the treatment of the revisions, which have to clearly be distinguished from errors. Indeed, the common revisions are notified systematically in publications and in the corresponding tables publish on the website. Errors, which can mislead users, require specific treatment and notification.

A. Error correction

1. Action

1.1 Error evaluation

In case of error detection, the information is passed on by the hierarchic channel to the relevant head of division, who decides on the severity and the necessity to inform the director. The procedures to be followed depend on the seriousness of the error and are described under section 1.3.

1.2 Error classification

The errors are classified in 3 categories:

• Tiny errors (typing errors in the text, broken links, formatting…)
• Minor errors (errors with no considerable effect, which do not appear in an important table, which are obvious for the reader and which do not concern the frequently updated data)
• Serious errors (considerable user groups are misled).

1.3. Procedures in case of error detection

In any case, the head of division informs the responsible of the unit “Dissemination and Communication” so that the information office is aware of the error while communicating with the users.

Tiny errors are corrected as fast as possible without any note in the publication

Minor errors are corrected on the website. A note saying " corrected version of (date) " is visibly published next to the link which points to the page or the file in question. The known users are not actively notified. The printed version is not corrected. In the colophon of every printed publication, it is mentioned that " if errors may occur, a corrected version can be found on the website … ".

In case of serious errors the publication (especially the press release) is removed from the website and corrected as quickly as possible. The director will be informed of the incident. The responsible unit immediately prepares a corrected version with an explanation on the correction, including the date of the correction. The title indicates that it is a corrected version and the list of publications on the website indicates the date of the corrected version. The note of the correction is visible, preferably on the homepage of the website. The users/subscribers are informed by newsletter/email. In certain cases, a corrigendum comes with the printed publications.

2. Gathering and analysing errors

2.1. Gathering informations on the errors

The Unit “Dissemination and Communication” conducts an error registry system. Every error has to be communicated to the Unit with the following information: detection date, correction date, degree of seriousness, description, cause, actions taken.

2. Error analysis

An error statistic and analysis is presented once a year in the framework of the quality reports. Status reports are presented at the monthly coordination meetings (StatCor). A more detailed analysis is undertaken for all those detected errors that might have an “educational value” so that similar errors could be avoided in future.

B. Revisions of figures

Procedures for revision of figures

There are two types of revisions:

1. The common periodic revisions of the provisional figures or forecasts (e.g. national accounts, economic or demographic forecasts). In the case of common revisions, no specific notification is necessary. The information on the status of the data is available in the metadata related to the relevant statistical tables.

2. The revisions of data series as a result of a methodological change. In this case, a notification is provided for the relevant tables or data. If a major revision occurs, as in the case of change in nomenclature (e.g. revision of NACE, revision of the European System of integrated Economic accounts - SEC), a release is issued to inform the pub.