The Wages of Election Modeling: Manifold vs. Metaculus
Putting forecasters to the test by simulating the gains (or losses) you'd make trading their recommendations on Polymarket every day
This is our 3rd forecaster match-up. See the original post in the series for more context on what’s going on here.
Previous match-ups:
The Rules
Forecasters start with $10,000.
Once a day, the forecasters get to buy or sell/short Trump shares, depending on whether their own odds are higher or lower than the Polymarket price.
The size of each trade is driven by the size of their bankroll and how certain they are of the mispricing - the bigger the mismatch, the bigger the trade.
We mark the holdings to market each day, so unrealized gains are reflected in daily account value.
A total of 48 trades are made, from September 19 through November 5. Any realized gains booked along the way are theirs too keep. After the election, all Trump shares pay $1 and Harris shares become worthless.
Manifold Markets vs. Metaculus
TL;DR Ignominy on both sides, once again, though far less so at
. By only losing 38.85%, they’ve not only easily dispatched Metaculus, but they’ve ousted previous record-holder DDHQ’s -38.88% (by a margin of just $2.49). As has been the case with every simulation thus far (with the exception of Nate Silver), both forecast’s Trump odds always lagged/tied Polymarket’s price. So there are once again zero long Trump trades, despite both contenders having Trump at or above 50% for 2 consecutive weeks.Below, we dive into the daily performance metrics - how the respective forecasters’ odds differed from market prices each day, how big a daily bet they place on Trump or Harris as a result, and how their portfolio value grew/shrank over time.
Previously…
