Prediction markets are literally markets.

You can’t have a market if the price is secret.

The goal isn’t to have people place bets and see who is right later. The goal is to expose the predictions to market forces and make people put their money on the line, thereby (theoretically) improving the quality of predictions.

Yes you can have market with secret price. Check out dark pools.

Dark pool prices aren't available to the general public, but they are visible to those participating in the market.

If you reduce transparency you also lose out on a lot of utility that centers around the wagered amount being an indicator of certainty.

Suppose you're using prediction markets to encourage thorough code reviews, specifically with an eye towards catching malicious commits. Run of the mill non-malicious PR's get lots of little yes wagers, and are merged without exceptional scrutiny from the package maintainers. Then a malicious commit comes along and a reviewer wagers $100 on "not merged". This captures the attention of the maintainers and they give the PR extra scrutiny. Turns out it has a malicious commit, so it doesn't get merged and the reviewer who found the flaw is rewarded with the money wagered by those who didn't find the flaw (plus some from the stakeholders, who seed the market with some "no" money to encourage participation in the game even in boring non-adversarial times).

If you hide the predictions and the amounts, you can't use the unsettled bets as inputs for decision making.

What do you mean by predictions are blind? The issue the parent is describing is (as an extreme case): I go on a prediction market for when someone will die, put all of my money on tomorrow, and then kill the person tomorrow.

You could imagine a lighter version where I ruh for some public office, bet a billion against me winning, and then drop out of the race.

The latter example is easily taken care of though, because there has to be a market to take your bet if the market has no reason to believe you would win your odds are really low thus your winnings over your billion are really low. On top of that your risk is not symmetric as you've exposed your self for some to now spend what millions to campaign for you and thus bet against that pool.

My point is your example is contrived and not really useful.

> What am I missing?

That by so preserving the independence of predictions, you’ve also removed their utility, which is predicated on their availability.

The price of a prediction depends on what people are currently predicting. So you can't keep it blind. Well I guess one way would be to put in limit orders on odds you're willing to take, and not revealing the market price. However I don't know if such a market condition / feature would have people using the prediction market.

If you know the price and payout of a bet, it's no longer blind. And if you don't, you wouldn't buy a ticket.

Sounds clever, until you realize you want to predict stuff before it happens

True, but speculators and those utilizing predictions to guide policy should be separate.

Why?

If you're not willing to speculate on your own predictions, how can anyone know how confident you are about them?

If you're not interested in guiding policy, why not go bet on horse races instead?