Phone data could end census

CENSUS questions could be replaced with mobile phone data following a successful test by the Office of National Statistics.

The plan is part of a Governmentbacked programme that could see the traditional questionnaire abandoned and other data sources, including phone records, used instead.

Phone data would allow the ONS to track where people live and work.

The agency has been carrying out experimental population analyses using different data sources since 2015, but this is the first to use data showing the location of phone users.

A report published on the ONS website yesterday revealed that the data showing commuting patterns, which was collected from Vodafone users aged 18 and over between March and April last year, matches well to corresponding census information collected in the 2011 poll.

The ONS has also examined how data from mobile phones could be used

to analyse ethnicity, wealth and population levels.

The research used anonymised information from Vodafone customers, tracking where the phones were overnight to find out a person’s home, and where they were during the day to conclude where they went to work.

It examined people who either lived or worked in one of three London boroughs.

The report concluded that the data matched well with the census information but overestimated the number of people working in the same borough as they lived. Analysts suggested that this could be because the data was mistakenly picking up other groups, such as students or people who travelled to the same area several times a week to go shopping, as commuting workers.

The ONS is now inviting responses so it can decide whether the method will be rolled out more widely.

The 217-year-old poll could be abandoned as early as 2023 if the pilot data is thought to be reliable enough.

Ian Cope, 2021 census director, said the plan had “huge potential”.