Factbombing: methodology

This is the methodology that we used for our factbombing article:

We aimed to determine how many factual claims were made during exchanges between Jeremy Corbyn and Theresa May at Prime Minister’s questions.

To do this, we analysed a year's worth of PMQs exchanges between the two (from 2 May 2018 to 1 May 2019, not including sessions where David Lidington and Emily Thornberry stood in).

We recorded how many claims Jeremy Corbyn and Theresa May made during each of their six statements, in each individual PMQs.

We defined a factual claim as a falsifiable assertion about the state of the world backed up by evidence, in order to further an argument. The evidence most typically comes in the form of a statistic, critical explanation of procedure, or a quotation. Below is an example of each:

A claim backed up by a statistic:

• “Homelessness is rising”.
• This is making an argumentative point about the worsening problem of homelessness, and points to a statistical trend to prove it.

A claim backed up by critical explanation of procedure:

• “The only way to avoid no deal is to accept a deal”.
• This is making an argumentative point that those who want to avoid no deal Brexit should back Theresa May’s deal. It is based on an explanation of the structure of Brexit proceedings, drawing out an internal logic to advance the point.

A claim backed up by quotation:

• “The Foreign Secretary said that the Prime Minister has not been asking for anything new in her discussions with the EU”.
• This is making an argumentative point that Theresa May’s discussions with the EU are proving fruitless. The quotation is directly linked to the argument, as it suggests that some of her closest colleagues share the opinion.

There are cases where these types of evidence were used, but did not advance an argumentative point. These were not counted as claims. Below are some examples:

Some statements of procedure are quite simply that. They lay some context, but do not advance an argument

• E.g. “We have seen amendments that seek to engineer a situation in which article 50 is extended.”

And some quotations are used to similar ends. If they are simply repeating critical quotes to try and embarrass their opponent, without using it to make a wider point or build a structured argument. We do not consider these claims.

• E.g. “Her friend the hon. Member for Totnes was right, was she not, when she said that the threat of no deal is “an absolute disgrace”?”

In addition, we do not consider statements that are value judgements, without wider evidence attached, to be claims.

• E.g. “She has shown no flexibility whatsoever on taking no deal off the table”

We also do not consider statements of intent, which do not refer to how that intention will come about, to be claims.

• “We will be protecting jobs in the UK”

We define factbombing as when an individual deploys a flurry of factual claims in quick succession, with no clear overarching point. There is no pure metric on which we assess when the status of factbomb has been achieved. Instead we apply our own judgment of when this criteria has been met.

For context, the smallest factbomb we identified contained 5 claims (Jeremy Corbyn’s third question on 4 July 2018) and the largest contained 15 claims (Jeremy Corbyn’s sixth question on 20 June 2018). Conversely, not all statements with a high number of claims are considered factbombs. The highest in this regard was Theresa May’s sixth answer on 9 January 2019, which included 11 claims but was not classified as a factbomb.