The 2018 Survey on Language Uses of the Population (EULP 2018) is an official statistical activity that is part of the Annual Programme for Statistical Action Programme (action 04 05 01), implemented by the Law on the Statistical Plan for Catalonia 2017–2020. The organisations in charge are the Ministry of Culture, through its General Directorate for Language Policy, and Idescat.
The EULP 2018 is the fourth edition of the Statistics on Language Uses in Catalonia, the previous ones have been in 2003, 2008 and 2013. In 2013 edition, Internet was incorporated as a new method of collecting data.
The main objective of the EULP 2018 is to find out the population of Catalonia's language identification and uses of Catalan and other languages in the different spaces where people interact, with specific interest in the situation of Catalan. These statistics aim to meet the need to have official data as needed for planning linguistic policies and for undertaking and assessing actions in the framework of the social use of language.
In order to achieve these objectives, the following information is collected and organised into the following thematic areas of a questionnaire:
A secondary objective, linked to the fact that this is an operation conducted every five years, is to observe changes in language uses over time.
The survey will be administered to people aged 15 and over who were included in Catalonia's Population Register as of 1st January 2018. A total of 9.000 people from all over Catalonia will be interviewed.
To choose the interviewees, Catalonia's Population Register was used, a government register that contains compulsorily updated information on residents included in the municipal population censuses of all the local councils of Catalonia. This register is in the care of Idescat and is regulated by the Law on Statistics in Catalonia.
The statistical system used is called random stratified sampling, which consists of randomly selecting a small number of people to represent Catalonia as a whole by territory of residence, with a representative sample for the Aran due to its linguistic peculiarities.
In order to ensure that the selected sample is a faithful reflection of the general population, it is very important for all the people selected to participate in the survey.
The individual information on the survey is protected by statistical secret under the terms set forth in the Law on Statistics in Catalonia. This means that the individualised data contained on the questionnaires may not be made public or disclosed to any person or entity, not even public administration, with the exception of any person or entity that is also bound by obligations to respect statistical secret. In this regard, all the personnel of Idescat and other organisations participating in official statistics in Catalonia must take a solemn oath to preserve the confidentiality of this information, and they are subjected to severe punishment should they violate this oath.
Likewise, the obligation for statistical secret is also extended to the publication of the results, meaning that both Idescat and the other organisations forming part of the Statistical System of Catalonia must take special care to ensure that individual information cannot be deduced from the tabulated information that is published.
Given the public interest, established by the Parliament of Catalonia, of all the the statistics included in the Statistical Plan of Catalonia, cooperation by both citizens and companies in responding to questionnaires is legally binding in order to ensure an appropriate number of responses and, in consequence, reliable statistical results (chapter 5 of the Law on Statistics in Catalonia).
The survey is conducted by means of a methodology that combines an Internet questionnaire, telephone or person-to-person interviews.
If the survey is conducted by Internet (CAWI), the respondent must use a username and password provided by ordinary mail as part of the letter of presentation of the EULP 2018 as received previously. If the respondent is reached by telephone a computer-assisted telephone interview (CATI) will be administered. If the person cannot be reached by telephone, they will be visited at their home in order to conduct a computer assisted personal interview (CAPI). In the latter case, the interviewer is inexcusably required to carry the credentials issued by Idescat with his or her photograph, full name, national identity number and interview ID code, which he or she is required to show to the respondent.
Only the person selected may respond to the interview; no other person may respond on his or her behalf. If the person selected is not available, another member of the household may not be interviewed in his or her place.
The fieldwork begins the first week of March 2018 and will last until September.
During the fieldwork period, a telephone number and email address are provided to deal with any queries which arise.