Annual Population Survey
The Annual Population Survey (APS) is a continuous household survey, covering the UK, with the aim of providing estimates between censuses of key social and labour market variables at a local area level. The APS is not a stand-alone survey, but uses data combined from two waves from the main Labour Force Survey (LFS) with data collected on a local sample boost. Apart from employment and unemployment, the topics covered in the survey include housing, ethnicity, religion, health and education.
Annual Population Survey. This is the Labour Force Survey plus various sample boosts.
An estimation procedure that constrains sample-based estimates of auxiliary variables to known totals (or accurate estimates). Calibration is used to improve the regional distribution of immigrants.
The nationality of the passport that the traveller is carrying.
This is the term used in the International Passenger Survey (IPS) to define the country for which a migrant is a passport holder. This refers specifically to the passport being used to enter / leave the UK at the time of interview. It does not refer to any other passport(s) which migrants of multiple nationality may hold. More generally a British citizen as described in IPS statistics includes those with UK nationality usually through a connection with the UK: birth, adoption, descent, registration, or naturalisation. British nationals have the right of abode in the UK.
Under this initiative, key information on migration and migration-related statistics collected across government are now jointly released. This allows for a principal point of access to these statistics and added value to the outputs in terms of insight, expert analysis and commentary to describe the similarities or differences between the data and why these occur.
Commonwealth (ONS Statistical Grouping)
The Commonwealth statistical grouping consists of countries of the Old Commonwealth and the New Commonwealth
A range within which the true value of a population parameter lies with known probability. For example the 95 per cent confidence interval represents the range into which there are 19 chances out of 20 that the true figure would fall (had all migrants been surveyed). This is obtained as +/- 1.96 times the standard error.
Country of usual residence
The country in which a person has a place to live, where he or she normally spends the daily period of rest. Temporary travel abroad for purposes of recreation, holiday, visits to friends and relatives, business, medical treatment or religious pilgrimages does not change a person’s country of usual residence (UN-based definition).
European Economic Area consists of the EU Member States plus
A person who leaves their country of usual residence to take up residence in another country for a period of at least 12 months.
An indication of the value of an unknown quantity based on observed data.
European Union as constituted between
1 January 1995
1 May 2004. The following 15 member states were included:
UK. For the purpose of producing international migration estimates between the
and the rest of the EU15, the
is excluded from this grouping. However, by convention, this grouping is still referred to as the EU15.
The EU2 (formerly known as the A2) are the two countries that joined the EU on 1 January 2007: Bulgaria and Romania. EU2 nationals currently have certain restrictions placed on them; in the first 12 months of stay, working Bulgarian and Romanian nationals are generally required to hold an accession worker card or apply for one of two lower-skilled quota schemes. Other Bulgarian and Romanian nationals can apply for a registration certificate, giving proof of a right to live in the UK. These restrictions are due to be lifted on 1 January 2014.
European Union as constituted between
1 May 2004
1 January 2007. The following 25 member states are included: Austria, Belgium, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, the Irish Republic, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden and the UK. For the purpose of producing international migration statistics between the
and the rest of the EU25, the
is excluded from this grouping. However, by convention, this grouping is still referred to as the EU25.
European Union as constituted on
1 January 2007. The following twenty seven member states are included: Austria, Belgium, Bulgaria, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, the Irish Republic, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden and the United Kingdom. For the purpose of producing international migration statistics between the
and the rest of the EU27, the
is excluded from this grouping. However, by convention, this grouping is still referred to as the EU27.
The EU8 (formerly known as the A8) are the eight central and eastern European countries that joined the EU on 1 May 2004: Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Slovakia and Slovenia. The EU8 does not include the two other countries that joined on that date: Cyprus and Malta. EU8 nationals previously had restrictions on their rights to work and were required to register under the Worker Registration Scheme, but these restrictions were lifted from 1 May 2011.
EU accession countries
The 12 countries that have joined the EU15 since
1 May 2004. These are
European Union (EU)
The EU consists of 28 countries: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Republic of Ireland, Romania, Slovakia, Slovenia, Spain, Sweden and the United Kingdom. Croatia joined the EU in July 2013 - data with a reference period after that date will include Croatia within the EU grouping.
Improving Migration and Population Statistics. The IMPS project aims to improve the accuracy of the Office for National Statistics population estimates and to establish where it is possible to introduce changes to data sources and methods that will improve the quality of the statistics. Further information on this project can be found on the National Statistics website.
In-country asylum seekers
Those asylum seekers who enter the
and do not apply on arrival at port but apply for asylum while in the
International Passenger Survey.
Labour Force Survey - a quarterly household survey run by the Office for National Statistics.
Long-term international migrant
Someone who moves to a country other than that of his or her usual residence for a period of at least a year so that the country of destination effectively becomes his or her new country of usual residence. From the perspective of the country of departure the person will be a long-term emigrant and from that country of arrival the person will be a long-term immigrant (based on UN definition).
Long-Term International Migration (LTIM)
Long-Term International Migration is produced by combining migration data from the IPS, international migration to and from Northern Ireland, Home Office data on asylum seekers and adjustments for visitor switchers and migrant switchers.
Mid-year population estimate
The estimated resident population on 30 June of the reference year. Estimates are based on the previous mid-year estimate aged on and adjusted for births, deaths, migration and changes in mobile sub-groups in the year to 30 June.
Travellers who stated the intention in the IPS to stay in the destination country for more than a year, therefore, counted as migrants but who actually left sooner.
National Population Projections
These are prepared by the Office for National Statistics who, in consultation with the devolved administrations, produce projections for the
and its four constituent countries. A new set of projections is normally made every second year, based on a full-scale review of the trends affecting the underlying assumptions about fertility, mortality and migration.
A person counted by the IPS but not interviewed. For example, during peak periods an interviewer may not finish an interview before their next assigned contact has crossed the IPS counting line.
Failure to obtain any survey information due to respondent refusal, non-contact or inability to reply.
Error attributable to all other sources other than sampling. Non-sampling errors may arise from many different sources. These may include misunderstanding or misreporting by respondents, variations between the way interviewers administer the survey, non-coverage of the population due to an inadequate sampling frame or sample design and errors made when processing the data.
Port asylum seekers
Those asylum seekers who apply for asylum at
A measure of the proportion of people contacted who respond to the survey.
The difference between an estimate derived from a random sample and the true population value; the difference being attributable to the fact that only a sample of values was used. That is, sampling error results because not every migrant who enters or leaves the
Standard error (SE)
An indication of the accuracy of an estimate and how much a sample estimate is likely to differ from the true value because of random effects.
Visitors who enter or leave the
intending to stay in the destination country for less than a year but who actually stay for a year or longer.