I believe Silver has overrated the odds of a Harris win, especially her odds of a clean sweep in the battleground states.
Understanding the Bet
The bet is for $1,000 which in two instances, described below, might become $2,000. This is an amount I can bet without getting the ire of someone special if I lose.
The above table, annotated by me, is from the October 27, Silver Bulletin 2024 Presidential Election Forecast.
I believe Silver understates Trump’s odd of winning overall (52.9 to 46.8) and overstates the likelihood of a Harris sweep of all the battleground states.
Battleground State Proposal
Nate Silver gets all the lines with an N. The total of those lines is 19.5 percent.
I get all the lines with an M. My total is 14.6 percent.
No one wins on the other lines.
I am giving Silver even odds on what he believes is a win-lose-tie proposition of 19.5 : 14.6 : 65.9.
In addition, I get Trump all but Michigan at 2.1 percent and give Silver all but Arizona at 3.0 percent.
Side Bet
For an additional $100 (my risk) I will take a Trump battleground sweep of all but Michigan at 40:1 odds when Silver says the odds are more like 50:1.
Silver’s risk would be $4,000.
What Gambler Would Not Accept These Bets?
I am offering Silver generally attractive odds. Casinos make a fortune off stuff like this.
However, if a person only had $1,000,000 and the bet was for $1,000,000 then no rational person would bet everything he/she had even on 2-1 odds (e.g. a person whose total net worth is $1,000,000 is offered 2,000,000 to correctly call a coin flip).
But this isn’t table stakes or a lose everything proposition.
Over time, in small bets, given a 5+ percentage point edge, with added side bonuses, a rational gambler would accept the bet I proposed, assuming they believed the odds are what they claim they are.
Why Might Nate Silver Refuse the Bet
First, I suspect Silver’s gut feeling is that his model is simply wrong.
I discussed this on October 24, in Nate Silver’s Gut Says Trump Will Win, Just Don’t Bet On It
Also see Nate Silver’s NYT Op-Ed Here’s What My Gut Says About the Election, but Don’t Trust Anyone’s Gut, Even Mine. That’s a free link.
The second reason Silver might refuse such a bet is he would hate losing a bet to a relatively unknown person out of fear of damaging his reputation.
A third reason he might refuse is on grounds of being flooded with similar offers. I dismiss this reason because Silver could easily state on acceptance of the bet that he automatically rejects, without discussion, any additional proposals.
The Most Likely Outcome
If Silver’s model is correct, the most likely outcome would be neither of us wins the bet. The odds of a tie are 65.9 percent.
That’s roughly 2-1 in favor of a draw with only a 14.6 percent chance for me and 19.5 percent chance for him.
Silver should be happy with that.
Nate, what’s your charity? Mine is the Les Turner ALS foundation.