IT WAS the pre-independence referendum pledge to the Scottish people that resulted in a bill for further financial and other powers.


But new research claims The Vow had very little impact on the Scottish referendum outcome.

The new study by University of Glasgow economists used Google Trends, a tool that traces terms people plug into a search, to analyse the significance of key events during the referendum campaign.

It's the latest development in Google's evolution from search engine to crystal ball, and now predicts everything from the success of an album or film - to the rate of flu infections in the coming winter.

The study indicates the TV debates did not have a substantial effect on the referendum result either and that the more information people searched for online, the less likely they were to vote for independence.

David Cameron, Ed Miliband and Nick Clegg united in The Vow two days before the referendum ballot to deliver "faster, safer and better change" for Scotland if it voted "No".

The joint pledge promised to give the Scottish Parliament increased powers and a fair share of resources although nationalists remained sceptical.

The Vow to give more powers to Scotland was seen by some as divisive and the gateway to the vote against independence.

However, the study showed that the key issue during nearly a year of the referendum campaign to August 16, 2014 was the issue of Scotland's future currency.

The authors, Ronald MacDonald and Xuxin Mao, said this "changed the whole structure of voters' opinion and resulted in a 4.3 percentage point increase in the potential Yes vote.

The "statistically significant" boost to the Yes vote came on the week of March 9 to 15, 2014, when George Osborne ruled out a formal currency union with an independent Scotland. That led to an increase in the possible Yes vote from 31.9 per cent to 36.2 per cent.

Authors of the new study said that after the rejection of the potential currency union Yes votes were driven by short-term emotion rather than long-term rationality.

But the YouGov opinion poll which gave Yes its only lead in the run-up to the ballot - with 51-49 percent over No - had a "significant positive effect" on the pro-independence vote, although no effect on information search activities.

The authors said: "There were claims that the television debate broadcast by the BBC and the interventions of three main Westminster parties, especially in terms of The Vow, determined the referendum path and contributed to the subsequent No victory.

"Interestingly, we find that for this final period in the referendum process that neither The Vow nor the last TV debate had any significant effect on the final voting results.

"And indeed swing voters tended to vote No after searching referendum-related information from Google.

"Our analysis shows that the key element in pushing the Yes vote to 45 per cent in the final lap of the referendum was the 'grassroots effect' of Yes voters on swing voters."

The authors said the use of Google Trends allowed them to make accurate predictions on the support for both sides of the campaign using data telling them what internet searches were taking place.

Ronald MacDonald, Adam Smith Professor of Political Economy at the University of Glasgow, said: "Over the course of the campaign, it appeared that the more information people searched for online, the less likely they were to vote Yes.

"After certain events, such as the rejection of the potential currency union by George Osborne, those identifying as Yes voters were more likely to be driven by short-term emotion than long-term rationality."

Professor MacDonald, one of the world's top experts on currency and a former adviser to the International Monetary Fund, was a former adviser to the Better Together campaign and a critic of the Yes campaign's currency policy.

The SNP said that the study was at odds with extensive polling carried out in the aftermath of the referendum which showed that 25 percent of people who voted No did so on the basis of the offer of further powers.

The Google Trends 'big data' analysis which began in August 2013 involved studying the volume of searches for particular keywords and search terms relating to key events in the referendum.

The researchers factored in assumptions including the theory that significant and positive effects lasting less than one week would be mainly 'emotional' and more than one week to be 'rational'.

Google's own researchers found that similar searches can track the spread of influenza and more recently showed that they "predict the present" with regard to economic indicators.

The University of Glasgow researchers believe that that the accuracy of these results show using internet search data may prove an increasingly valuable way of accurately analysing future election results as they happen.