The battle for super forecasters is heating up
The UK could hit a million Covid cases per week. The pandemic will be over in October. The next variant of Covid could kill one in three people and we will live with the virus forever. These statements may sound contradictory, but they are in fact all predictions made by some of the country’s top epidemiological modelers over the past month.
Since the start of the pandemic, the UK’s pandemic predictors have become the government’s closest to a crystal ball. Already, the work of these super forecasters has become instrumental in shaping policies, from containment to vaccinations. The future of the economy, our arts and culture all depend on what these forecasters say about the risk of Covid.
“If 2020 isn’t a galvanizing shock enough to say we need to take science and technology seriously… then I don’t know what it would be,” Dominic Cummings told MPs earlier this year (in the one of his most practical comments). But science can also be political – and super forecasters don’t always agree. Their age, political biases, and even romantic histories have all been suggested as reasons for their varying predictions as well as the competitive nature of the field, with scientists and academics vying for funding and positions for a rare moment in the limelight. .
The last line is global. He sees Nate Silver, the founder of US opinion poll analysis giant FiveThirtyEight, which correctly predicted the outcome of the 50 states in the 2012 election, against Professor Neil Ferguson of Imperial College London, in a macho modeling bun fight. Silver started it off by saying: ‘Covid cases have fallen to 33,000 a day (seven-day average) since Neil Ferguson, perhaps the UK’s most prominent epidemiologist, said he was “almost inevitable” that the cases reached 100,000 per day. I don’t care if the prediction is wrong, I’m sure this stuff is hard to predict. It’s just that he’s always so overconfident. Now he says he’s “positive” the pandemic will be over by October. We probably will. But there are downside risks: new variants, declining immunity, etc.
Canadian-American political science writer Philip Tetlock (and author of the Cummings-endorsed book Superforecasting) weighed in: “Expect even the best forecasters to make a lot of mistakes. When smart forecasters are consistently overconfident, start to suspect that they are not playing a game of sheer precision. In other words, just because the predictions are bold doesn’t mean they’re correct.
So who should we believe? And how good can we expect these modellers to be correct, anyway? From professors fighting for lockdown to the controversial herd immunity debate, this is how modelers go to war.
One of Covid’s oldest culture wars has been between those for and against any form of foreclosure. On the one hand, Ferguson, a mathematical epidemiologist at Imperial College London. The thin, bespectacled 51-year-old has a resume dating back to the foot-and-mouth disease crisis and quickly became the mastermind of lockdown modeling in the UK alongside Sage (Scientific Advisory Group for Emergencies), his predictions leading to the introduction of the first stay-at-home restrictions and social distancing (although he now says it will be over by October). He met Dr Sunetra Gupta, 56, a theoretical epidemiologist at the University of Oxford and one of the most controversial figures in the debate, who believes herd immunity is the way to go. The eminent academic and romantic novelist – she has written four – has been called Professor Reopen for her calls for the immediate resumption of a “normal life” for everyone except the “vulnerable”, set out in his so-called Great Barrington Statement, co-authored with Professors Jay Bhattacharya and Martin Kulldorff. Ferguson and Gupta both say their models are based on science – so how much of their contrast in forecasting comes down to politics?
The future of the economy, of our arts … depends on what these forecasters say about the risk of Covid
Gupta denied the “slanders” claiming that she was affiliated with right-wing groups or that her work was pseudo-science, insisting that she was “more left than working” and that her statement represented both right and left politics. Ferguson’s Twitter feed, meanwhile, suggests he’s more comfortable on the left. He praised Lib Dem MP Layla Moran on her electoral victory in 2017 and the woman he was caught breaking the lockdown with for having an affair with last year, Antonia Staats, is a left-wing activist. Others believe there was a broader politics involved in the Ferguson and Gupta nerd-off. Mike Hulme, professor of human geography at Cambridge, suggests that Sage’s ‘panicked’ lockdown policy with Ferguson was influenced by his own ‘at risk’ members – just look at their average age, he said. October of last year. Another controversial area for modelers is collective immunity.
“There is a lot of evidence to suggest that immunity plays a role in reducing epidemics,” Gupta said in an interview last year. Scientists initially estimated that 60 to 70% of the population needed to acquire resistance to the virus to banish it – this is still the figure cited by the World Health Organization – and in April, scientists from the ‘UCL, led by Professor Karl Friston, claimed that Britain would get collective immunity (73.4% of the population) within days. Friston’s prediction was quickly challenged and over time the collective immunity debate grew increasingly murky. According to Stefan Baral, associate professor of epidemiology at Johns Hopkins University, there is “enormous fear in the scientific community” when it comes to denouncing organizations like the WHO. Model makers can of course change their mind.
Meanwhile, Dr.Anthony Fauci, an infectious disease expert and adviser to the US president, began to raise his estimate of herd immunity. He now believes it might take more than 90% immunity to stop the virus. “Things are going to get worse,” he told the Wall Street Journal, pointing to the more contagious Delta variant. Now, many are calling for a new definition of collective immunity. “We need to carefully define collective immunity when we think about the future,” said Professor Christl Donnelly, University of Oxford and Imperial College. But how much hope can we invest in this future?
“I am sure that by the end of September / October we will get back to most of the pandemic,” Ferguson told BBC Radio 4 late last month. He is widely known for his pessimistic predictions, so should this give the British public hope?
Not quite, according to statistician Silver. Writing on Twitter, he noted that Ferguson was “consistently so overconfident,” warning of the risks of new variants and declining immunity. Tetlock explained that a phrase like “serious possibility” could mean 20% chance for one person and 80% chance for another.
There is a lot of fear in the scientific community when it comes to speaking out
Silver and Tetlock are not alone in their concerns. Ferguson’s prediction flies in the face of a recent warning from Sage of a “risky” fall and, more worryingly, that a new variant could kill up to one in three people is a “realistic possibility”. Meanwhile, his eponymous rival Niall Ferguson, a history professor at Harvard, told Bloomberg he believes we should be ready to live with Covid “forever”. “We may still be languishing in the second trimester of this pandemic – or maybe it’s early in the second half,” he said.
Tetlock says there is an inverse correlation between the fame of forecasters and their ability to predict outcomes. Certainly, one thing is certain: the Covid crystal ball is cloudier than it looks.