"Highly dubious" polls showing gains for the Brexit Party are being pushed by a polling organisation run by a pro-Brexit payday loans broker.
PollsdotUK has been criticised by respected polling organisations who analysed its findings for Sky News.
These experts noted it was not a member of the British Polling Council, which aims to establish a minimum standard of transparency among pollsters.
The identity of the people behind PollsdotUK is not stated on its website, but the domain is registered to Graeme Wingate, a pro-Brexit activist on Twitter, via his payday loans brokerage firm QuickLoans.
Mr Wingate also runs a self-certification mortgages company which targets customers in the UK from Prague, despite these mortgages being banned in the UK. The company advertises its services as being outside of the jurisdiction of the UK's Financial Conduct Authority.
Mr Wingate has not responded to enquiries from Sky News, although the PollsdotUK website was updated following our attempts to contact him to criticise "certain parts of the media".
The site now reads: "This site is not part of the Brexit Party. It has never been in any communications, directly or indirectly with the Brexit Party or anyone on behalf of the them at any time."
Before it was edited, the site explained its methodology by claiming it used raw data rather than data which had been weighted against the profile of the population.
Election analyst Matt Singh explained that this undermined the scientific basis of the polling, which uses demographic information to check that its respondents are representative of the population.
Mr Singh said: "It is sometimes claimed that weighted data is a form of 'manipulation' intended to achieve a particular result, but the purpose of weighting is to ensure that the sample reflects the population.
"In other words, if the raw sample has too many of one demographic group, that group is weighted down; too few and it is weighted up.
"Since the site additionally doesn't publish tables - which effectively means it doesn't show its working - we have no idea whether it has the right proportions of men and women, young and old people, graduates and non-graduates, and so on.
"There is no reason to think that polls like these - that make no attempt to ensure a sample that's representative of the population - are accurate, and they should be ignored."
Professor Will Jennings of the University of Southampton concurred, describing the site's polls as "highly dubious" - and experts have also raised significant questions about its methodology for constituency-level polling.
The polls are being spread in pro-Brexit Facebook groups - but there is no indication they are strategically designed to impact the ultimate vote in specific constituencies, nor that they are part of a coordinated disinformation campaign.
PollsdotUK claims to have focused its "limited resources on marginal seats" such as Dudley North, a constituency where it claims to have spoken to 1,264 respondents in just two days.
Joe Twyman, the co-founder and director of Deltapoll, said he was surprised by these numbers.
"Speaking to 1,000 people face-to-face usually takes a minimum of 10 days, even with a large team of interviewers," Mr Twyman explained.
"Even if you assume working from 8am to 9pm for two days that would mean you would have to get nearly 49 people an hour, every hour, to complete the survey.
"By telephone it's even worse. Response rates by telephone surveys are usually around 5% to 10%. Even if we are very generous and give them a 10% response rate that means they have to make 486 answered calls an hour, every hour from 8am - 9pm for two days."
This would mount to more than eight calls a minute - or roughly one every seven-and-a-half seconds.
Mr Twyman added: "In my professional experience (as a political researcher with over 20 years of experience, as a director at the founding of YouGov, as a project director for the last five British Election Studies and as someone who has lectured in survey research methods at Cambridge University, and a load of other places too) this work is not legitimate and should be discounted."
Under the Radar is a Sky News project to investigate online political activity throughout the election, from targeted ads to disinformation
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