Uncertainty over net-migration statistics explained

August 31, 2012, Oxford University

The true statistics for net migration could be 35,000 higher or lower than official estimates, Oxford University's Migration Observatory has said after the Office for National Statistics (ONS) released the provisional estimate for net migration in 2011 today (30 August).

The central estimate for net migration in 2011 was 216,000 – a fall of 36,000 from 2010's estimate of 252,000. But for the first time, ONS also released the margins for error associated with its net-migration statistics with the result that net migration could be 35,000 higher or lower than estimated.

The ONS notes that the 2011 in the estimate of net-migration is 'not statistically significant' – which means that it cannot be said for certain that net-migration has actually declined, despite the fall in the central estimate.

This is because the migration are primarily based on a sample survey – the International Passenger Survey (IPS) – which, as is the case with all surveys, produces estimates that are subject to margins of error.

Dr Martin Ruhs, Director of the Migration at the University of Oxford, said: 'There is a constant desire among policy makers in all parties, the press and other in having 'hard' facts and specific numbers about migration, but the reality is that sometimes these are simply not available.

"The uncertainty around the official migration estimates means that the figures need to be used and interpreted with great care."

He added: "The in the UK's migration estimates also means that it is very difficult to assess how well the government is progressing toward its target of reducing net-migration to the 'tens of thousands', or to evaluate the effects of specific policy changes."

"In simple terms, the Government could miss the "tens of thousands" target by many tens of thousands and still appear to have hit it – conversely the Government could hit, or even exceed its target and still appear to have missed it."

Explore further: The net migration 'bounce'

More information: A comment piece by the Migration Observatory explores the importance and profound implications of this uncertainty for the UK's migration debate.

Related Stories

The net migration 'bounce'

March 5, 2012

New analysis by Oxford University’s Migration Observatory shows that any short term cut to net-migration brought about by reductions in immigration will be partially reversed in the long term because of declining emigration. ...

Puffins 'scout out' best migration route

July 21, 2011

(PhysOrg.com) -- Individual Atlantic puffins 'scout out' their own migration routes rather than relying on genetic ‘programming’ or learning routes from a parent, a new study suggests.

Migration an overlooked health policy issue: New series

May 24, 2011

If internal and international migrants comprised a nation, it would be the third most populous country in the world, just after China and India. Thus, there can be little doubt that population mobility is among the leading ...

Recommended for you

Unprecedented study of Picasso's bronzes uncovers new details

February 17, 2018

Musee national Picasso-Paris and the Northwestern University/Art Institute of Chicago Center for Scientific Studies in the Arts (NU-ACCESS) have completed the first major material survey and study of the Musee national Picasso-Paris' ...

Humans will actually react pretty well to news of alien life

February 16, 2018

As humans reach out technologically to see if there are other life forms in the universe, one important question needs to be answered: When we make contact, how are we going to handle it? Will we feel threatened and react ...

Using Twitter to discover how language changes

February 16, 2018

Scientists at Royal Holloway, University of London, have studied more than 200 million Twitter messages to try and unravel the mystery of how language evolves and spreads.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.