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Row over tactical voting site
News UK general election Polling
Row over tactical voting site Campaigners under fire for their statistical model for tactical voting
James Ball
calculator. It used a relatively new form of election modelling known as MRP, short for multilevel regression and post-stratification. “MRP isn’t polling, that’s the key thing that people probably don’t quite understand,” says Smith. Instead, it is a model that takes a large initial polling sample (more than 46,000 voters in this case) and combines it with numerous other factors (90,000 for this A new way of modelling is being used to offer pro-Remain voting advice
model) to make much more granular predictions about the behaviour of constituencies – and even individuals. The method saw a boost in 2017 when polling firm YouGov released an experimental MRP on the eve of the election, correctly identifying the winning party in 93 per cent of seats. Chris Curtis from YouGov says the principle behind MRP is to model types of voters, rather than relying on traditional constituency polling. For example, an MRP will model the behaviour of a 24-year-old
woman in the north-east of England with a degree, then work out how many such people there are in different constituencies. It then assesses other factors, such as how marginal a seat is, as voters in marginal seats are more likely to switch parties than those in safe seats. It also calculates incumbency effects, which particularly boost an MP’s first election as the incumbent. The techniques behind MRP are decades old, but are largely a new factor in politics. This is partly because existing polling techniques are becoming less effective as it gets harder to reach balanced samples, and also because online polling decreases the cost of the large-scale polls needed to power the models. There are limitations, of course, not least that during an election campaign, voters change their minds. Smith says Best for Britain is planning to update its model closer to election day. “MRP is still just like all polling, telling us where the public is right now,” says Curtis. “It is not predicting the future.” ❚
The decision follows the UK spending watchdog saying last month that fracking had cost police forces and public bodies £33 million, and that the
would ban fracking permanently. Prime minister Boris Johnson has said the environment will be one of his top three domestic priorities. Opposition to fracking has long outstripped support in official polling. Although environmentalists welcomed the fracking moratorium, on the same day officials also gave the green light for the country’s first deep coal mine in decades, near Whitehaven in Cumbria. ❚ Adam Vaughan
ALEX SEGRE/ALAMY STOCK PHOTO
THE UK general election campaign has begun, with voters having to decide whether to support the current Conservative government, which wants to proceed with leaving the European Union, or try to replace it. A pro-EU campaign group, Best for Britain, has launched a tactical voting guide designed to help elect politicians who want to change course on Brexit. The tool has been criticised for giving what some see as odd advice, but the group says its choices are backed by complex statistical modelling. The Liberal Democrats are the most anti-Brexit UK party, with a policy of notifying the EU that the country no longer wishes to leave. However, it is also a minor party, meaning its chances of winning many of the 650 seats are seen as slim. Despite this, Best for Britain suggests a Lib Dem vote in 99 seats where the party trailed the incumbent by at least 25,000 votes in the 2017 general election. Best for Britain CEO Naomi Smith says this advice isn’t due to partisan bias, but rather the result of how the group powered its
Energy
Fracking banned as UK parties compete on green credentials THE UK government has brought in a moratorium on fracking in England and dropped measures to speed the development of shale gas wells, ringing the death knell for the nascent industry. The sharp reversal of support ends nearly a decade of protests, court cases and minor earthquakes without any energy being produced. The move comes after fracking caused a magnitude-2.9 quake 8 | New Scientist | 9 November 2019
in August near Blackpool. It is the largest so far after operations by shale firm Cuadrilla in the past year. A scientific analysis published last week by the UK oil and gas regulator concluded that bigger future tremors couldn’t be ruled out, which could cause unacceptable “damage and disturbance”. Although the moratorium applies only to England, fracking is already effectively banned in Scotland and Wales. Opposition political parties have pledged to ban the method of extracting gas. The UK government also ditched controversial planning reforms to aid the industry.
2.9
The magnitude of a fracking-related earthquake in August industry’s progress had been slower than expected. The opposition Labour party accused the government of trying to win over voters in next month’s general election. It said that it
For more on climate change in the UK election, see page 18
Row over tactical voting site Campaigners under fire for their statistical model for tactical voting
James Ball
calculator. It used a relatively new form of election modelling known as MRP, short for multilevel regression and post-stratification. “MRP isn’t polling, that’s the key thing that people probably don’t quite understand,” says Smith. Instead, it is a model that takes a large initial polling sample (more than 46,000 voters in this case) and combines it with numerous other factors (90,000 for this A new way of modelling is being used to offer pro-Remain voting advice
model) to make much more granular predictions about the behaviour of constituencies – and even individuals. The method saw a boost in 2017 when polling firm YouGov released an experimental MRP on the eve of the election, correctly identifying the winning party in 93 per cent of seats. Chris Curtis from YouGov says the principle behind MRP is to model types of voters, rather than relying on traditional constituency polling. For example, an MRP will model the behaviour of a 24-year-old
woman in the north-east of England with a degree, then work out how many such people there are in different constituencies. It then assesses other factors, such as how marginal a seat is, as voters in marginal seats are more likely to switch parties than those in safe seats. It also calculates incumbency effects, which particularly boost an MP’s first election as the incumbent. The techniques behind MRP are decades old, but are largely a new factor in politics. This is partly because existing polling techniques are becoming less effective as it gets harder to reach balanced samples, and also because online polling decreases the cost of the large-scale polls needed to power the models. There are limitations, of course, not least that during an election campaign, voters change their minds. Smith says Best for Britain is planning to update its model closer to election day. “MRP is still just like all polling, telling us where the public is right now,” says Curtis. “It is not predicting the future.” ❚
The decision follows the UK spending watchdog saying last month that fracking had cost police forces and public bodies £33 million, and that the
would ban fracking permanently. Prime minister Boris Johnson has said the environment will be one of his top three domestic priorities. Opposition to fracking has long outstripped support in official polling. Although environmentalists welcomed the fracking moratorium, on the same day officials also gave the green light for the country’s first deep coal mine in decades, near Whitehaven in Cumbria. ❚ Adam Vaughan
ALEX SEGRE/ALAMY STOCK PHOTO
THE UK general election campaign has begun, with voters having to decide whether to support the current Conservative government, which wants to proceed with leaving the European Union, or try to replace it. A pro-EU campaign group, Best for Britain, has launched a tactical voting guide designed to help elect politicians who want to change course on Brexit. The tool has been criticised for giving what some see as odd advice, but the group says its choices are backed by complex statistical modelling. The Liberal Democrats are the most anti-Brexit UK party, with a policy of notifying the EU that the country no longer wishes to leave. However, it is also a minor party, meaning its chances of winning many of the 650 seats are seen as slim. Despite this, Best for Britain suggests a Lib Dem vote in 99 seats where the party trailed the incumbent by at least 25,000 votes in the 2017 general election. Best for Britain CEO Naomi Smith says this advice isn’t due to partisan bias, but rather the result of how the group powered its
Energy
Fracking banned as UK parties compete on green credentials THE UK government has brought in a moratorium on fracking in England and dropped measures to speed the development of shale gas wells, ringing the death knell for the nascent industry. The sharp reversal of support ends nearly a decade of protests, court cases and minor earthquakes without any energy being produced. The move comes after fracking caused a magnitude-2.9 quake 8 | New Scientist | 9 November 2019
in August near Blackpool. It is the largest so far after operations by shale firm Cuadrilla in the past year. A scientific analysis published last week by the UK oil and gas regulator concluded that bigger future tremors couldn’t be ruled out, which could cause unacceptable “damage and disturbance”. Although the moratorium applies only to England, fracking is already effectively banned in Scotland and Wales. Opposition political parties have pledged to ban the method of extracting gas. The UK government also ditched controversial planning reforms to aid the industry.
2.9
The magnitude of a fracking-related earthquake in August industry’s progress had been slower than expected. The opposition Labour party accused the government of trying to win over voters in next month’s general election. It said that it
For more on climate change in the UK election, see page 18