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Re:An election forecast that's 50-50 is not "giving up." by James_K on Tuesday March 11, 2025 @12:09PM (#43333911)
Suppose it rains on 50% of days. One forecaster gives a 50% chance of rain every day. Another gives a 90% chance of rain/not rain and is "wrong" 10% of of time. Both stations are giving you accurate information from a probability perspective (when station A says a 50% chance, you know there's a 50% chance of rain tomorrow, when station B says 90%, you know there's a 90% chance of rain tomorrow) but the 50% chance station is less useful as the number is lower. They have effectively given up in the same way pollsters have given up.
Re:An election forecast that's 50-50 is not "giving up." by DiggyJohnson on Tuesday March 11, 2025 @12:33PM (#43334189)
This is the best response in thread, imo. Is there a term for this phenomenon?
Re:An election forecast that's 50-50 is not "giving up." by James_K on Tuesday March 11, 2025 @12:39PM (#43334278)
I don't think so, though I often find someone has thought of the same thing I have and given it a name. The root of the issue is a matter of language. Events don't have probabilities. You don't predict a 50% chance of rain, you predict rain with a 50% certainty. (There are a lot of internet brain teasers that exploit this subtle ideological difference.) The 50% is talking about how often you're correct, not how likely the rain is to happen. Probabilities don't really exist; it either rains or it doesn't.
Re:An election forecast that's 50-50 is not "giving up." by gowld on Tuesday March 11, 2025 @02:23PM (#43335515)
It's statistical information arbitrage.

Let's say you go to the futures market:

Seller pays a contract-buyer $1 if it rains tomorrow. How much will seller charge for that contract?

Bookmaker using forecaster A will sell that contract for $0.51 every day, and earn a profit of $0.01/contract, on average.

Bookmaker using forecaster B and their clients will buy that contract on probably sunny says, and bankrupt Forecaster A.

Similar result if Bookmaker B sells contracts to Bookmaker A, at $0.11 on probably-sunny days, and $0.90 on probably-rainy days.