I was asked about government data in the election, so I thought today I would share with you my reply:
I entirely agree that we need to improve the skills of our nation in handling and using data. The government is planning more emphasis on science, maths and data, which will be covered by new T levels as well.
I also agree that new policies should be underpinned by evidence. That is the approach I have always adopted as policy adviser and as someone involved in the national debate over major concerns.
There are issues both over the quality of data available to government and over the way some choose to interpret or use it. I myself use a lot of the economic data for the interventions I make in the national debate on public spending, economic growth and taxation. All too often the basis of a series is changed making comparison over time more difficult. There are regular changes to the back data, long after the intense political debate about the numbers has passed on. We often find the sharp political exchanges have attacked and defended wrong numbers.
The current changes being put through on inflation are an example of the complexity, with RPI giving way to CPI now giving way to a new index which includes a proxy for owner occupied housing costs which may not capture the reality. This is an example of an important index which has consequences for people’s lives, as benefits are uprated and index bondholders rewarded by reference to one or other of these indices.
In some of the important figures for debate the independent officials make forecasts which can have great political significance. For example, the OBR forecast poor revenues for the almost completed 2016-17 year in the November Autumn Statement, only to have to put back £8bn of revenue they left out from the November forecast in the March update. It is a good job the government did not respond to the November figures by cutting spending or increasing taxes to keep the deficit on target, as it turns out it was not off target as I argued at the time. There are always dangers in official figures that require judgements or rely on models which have not in the past accurately reflected what has happened.
The UK economic figures are subject to revision for many years after the date to which they apply. IT reminds us that decision takers often do have to make judgements without access to proper data. That is another area where a democratic system has its advantages. If the decision takers are in touch with those most affected, they will know qualitatively about the problem and the solutions which can help avoid a mistake based on partial, inaccurate or misunderstood data.
You can rest assured I will continue to highlight problems, working to our shared goal of more accurate numbers used intelligently and fairly to underpin policy.