In Defence of Liberty

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I told you I would need to say this again.

Once again, Dr Eoin Clarke repeats his mistake on zero-hours contracts.

“Employment” figures

After the Labour Left account called the “employment” figures a “sham”, I pointed out that the proportion of the UK labour force on a “zero-hours contract” rose to 2.5%, from 2.3% [1].

This is taken from the Labour Force Survey, where a person is employed (having done at least an hour of paid work in the week before they were interviewed or reported they were away from their job), report that they have some flexibility in their contractual arrangements, and recognise that they are on a “zero-hours contract”.

As stated in the very report that Dr Clarke (through the guise of the Labour Left account) links to:

Comparisons with 2012 and earlier years are complicated by a large increase between 2012 and 2013, which appeared to be mainly due to increased recognition of “zero-hours contracts”.

Despite these methodological limitations, Dr Clarke states — without caveat — that “Zero hours contracts up 630,000 under Cameron”. Now, Dr Clarke compounds this error by putting on the chart:

The ONS says this data has a coefficient of variation of +/- 5% & can be considered “reasonably precise”.

Statistical accuracy

Now, any person who looks at that chart and decides that the spike between 2012 and 2013 is unworthy of note is not an analyst. Any person who omits such a severe caveat from the data’s source has no care for statistical accuracy.

Dr Clarke is honestly suggesting that the number of people employed on zero-hours contracts was 250,000 in 2012, and this figure jumped by 333,000 to 583,000 in 2013.

Over half of claimed increase (“up 630,000 under Cameron”) occurred in one year. This is close to the entire increase in total employment between October to December 2012 and the same period in 2013: which was 396,000 [2].

The statement that Dr Clarke backs — that the entire increase is real and not driven by increased salience of the “zero-hours contract” term — is supported by neither the Office for National Statistics nor the UK Statistics Authority [3].

Great care should be taken when assessing the prevalence of zero-hours contracts, especially between 2012 and 2013. The employment figures compiled by the Office for National Statistics are not a “sham”.


[1] ONS, 2016. Contracts that do not guarantee a minimum number of hours: March 2016. Available from: [Accessed: 18th March 2016]

[2] ONS, 2014. Labour Market Statistics, February 2014. Available from: [Accessed: 18th March 2016]

[3] UKSA, 2014. Letter from Sir Andrew Dilnot to Chuka Ummuna, 2014. Available from:—correspondence/correspondence/letter-from-sir-andrew-dilnot-to-chuka-umunna-mp-230514.pdf [Accessed: 18th March 2016]


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