Leonardo Carella @leonardocarella
As promised, here's what @benwansell and I found out about actually-existing electoral deals, "unilateral alliances" and hypothetical pacts. What's a "Tim Walker Pact"? Do you want to know what's a "Reverse Farage" or are you too afraid to ask? Read on and you'll find out. (1)
We started from Ben's general election simulator, which draws on both current polling and 2017 results to predict English and Welsh constituency results, and added a Scotland mini-model alongside it. Based on current polling, we simulate 2,000 election results for E&W. (2)
Then we plug in the values for UK-wide parties from each electoral simulation in the Scotland mini-model, and get Scotland shares. Then we translate the shares into seats: the predictor offers various options as to how to do it, but we're starting with UNS assumptions. (3)
In the baseline scenario, with no alliances, and with distribution centered around polling averages of 38 Con 28 Lab 15 LD 8 BXP 4 Green 1 PC and SNP 39% in Scotland: we get
drumroll
Conservatives have a 78% probability to get a majority, Remain parties only 12%. (4)
"But what about the LibDem/Green/Plaid Cymry alliance?!" I hear you ask. Fear not. It turns out that on average it changes between one and two seats. The density plots are almost identical. (5)
Same story for the "unilateral alliance", whereby the Brexit Party stands down their candidates in Conservative-held seats (left). On average, about 4 seats change hands. And if you plug in both alliances at the same time, they essentially cancel each other out. (6)
^So, alliances don't work - or do they? What could they have done better? Here's where the Reverse Farage comes in. What if Farage had stood down candidates in Labour-held seats? It would have been much more effective. Conservatives now have 84% chances of a majority (7)
And what if the Brexit Party had gone all the way and stood down everywhere? Up against existing Unite-to-Remain alliance, the Conservative chances of a majority up to 88%, with a median expected number of seats of 360. We call this 'The Full Farage'. (8)
Let's assume for a second that Remainers were any good at politics - I know, it's a challenging thought experiment... But what kind of alliance would they strike?
A few days ago, Tim Walker, the LibDem candidate in Canterbury, stood down and endorsed the Labour incumbent. (9)
Assuming 70% vote transfers (we don't have any polling on this, so we guessed), if Labour and the LibDems did stood down in the seats held by the other nationwide, Remain would have 49% chances of a majority, higher than the Conservatives' 35% (10)
Now suppose they went all the way and stood down in every seat endorsing the most likely Remain winner (as recommended by Best for Britain's MRP model for E&W, and the highest polling in 2017 for Scotland). 74% chances of a Remain majority, Labour averaging 260 seats. (11)
We jotted down our thoughts on what all this means in an upcoming piece for @UKandEU. Head there for more details, caveats and hot takes!