I want to make a prediction. But I want to do it like this:
- Keep the prediction secret, indeed even keeping secret what the prediction is about.
- Have the prediction revealed at some pre-specified future date.
- Have it certified that the prediction was recorded on a certain date and not changed after that.
Is there a web service that facilitates predictions like this? It would be a useful service. There are probably lots of reasons someone would want to keep their predictions secret prior to the resolution: you don’t want your prediction to be self-fulfilling (or self-defeating), you don’t want others to know what you are predicting about (maybe it arises out of some proprietary research), or you want to trade anonymously on your prediction.
If anyone has any ideas, please let me know in the comments below.
Addendum: Mallesh correctly points out in the comments that the system would have to publicize that you made a prediction. This I want to do.
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November 12, 2010 at 2:04 pm
Mallesh
There’s a problem here, right- if the fact that you made a prediction isn’t made public, you can always make multiple predictions that are mutually exhaustive, and ex-post only claim that you predicted the event that realized… Even if the fact that you made a prediction is public every time you make it, verifying that you didn’t make a contradictory prediction would require me opening up all the other predictions you made to date.
On trading- this must be easier- I’d have thought a good Vegas bookie would happily give you odds on any event and you could bet.
Out of interest what did you have in mind?
November 12, 2010 at 2:09 pm
jeff
yes mallesh, thanks i forgot to add that.
November 12, 2010 at 2:08 pm
Alfredo
It’s an excellent idea, but there is noly the issue of making several predictions for the same event. If there aren’t the mechanism would not be reliable. If it is secret you can always predict something both ways and after its occurrence only reveal the one that is more convenient for you.
November 12, 2010 at 2:10 pm
jeff
yes, i want to be able to announce “i have made a prediction at http://www.certifiedpredictions.com, its serial number is 12345 and you will find out on date XYZ what the prediction was.”
November 12, 2010 at 2:15 pm
mph
You could write your prediction, compute the hash of that text with SHA-1 (or similar), and immediately post on your blog the SHA-1 hash and the date on which you will reveal the prediction.
November 12, 2010 at 2:19 pm
jeff
nice. it works for me as a blogger because blog readers can archive their own copy of the hash in case i change the prediction, generate the new hash and go back and modify the original post.
November 12, 2010 at 2:27 pm
jeff
although i still have the option of not revealing anything.
November 12, 2010 at 2:51 pm
Anonymous
Here is one way, but maybe a presumably costly way. Learn a different language, say, Chinese. Register an account in a well-known blogging website in China (that is the only reason to learn some Chinese:), then write the prediction in English as a blog! By doing this, no one will understand what your prediction is~Moreover, you are not able to change the date or the content of your prediction without the permission of the administrators of the website.
November 12, 2010 at 2:52 pm
Heng
Here is one way, but maybe a presumably costly way. Learn a different language, say, Chinese. Register an account in a well-known blogging website in China (that is the only reason to learn some Chinese:), then write the prediction in English as a blog! By doing this, no one will understand what your prediction is~Moreover, you are not able to change the date or the content of your prediction without the permission of the administrators of the website.
November 12, 2010 at 4:40 pm
Oliver Steele
It was traditional to use a Latin anagram for this, as an early form of hashing (with more collisions than modern techniques). http://en.wikipedia.org/wiki/Anagram#Establishment_of_priority
November 12, 2010 at 8:14 pm
dan
I think a similar problem/desire was faced by the authors of:
arxiv.org/abs/0911.0454
The Financial Bubble Experiment: advanced diagnostics and forecasts of bubble terminations by Didier Sornette, Ryan Woodard, Maxim Fedorovsky, Stefan Reimann, Hilary Woodard, Wei-Xing Zhou
They solved it by publicizing SHA1 digests of documents for timed later release. Actually their predictions might be more “complicated” than yours. Predictions requires a strict specification of the setup to preclude ex-post reinterpretation of the prediction.
November 13, 2010 at 12:11 am
Jonathan Weinstein
Interesting; I was thinking of public-key encryption. I had not heard of SHA-1. If I understand correctly, it differs from RSA in being many-one, hence having no possible decryption key…but we don’t need decryption for this application. Cute.
November 13, 2010 at 1:51 am
Kevin Burke
You could also make a bet on intrade.com or similar, and hang on to the receipt. Then after the event passes you can print the receipt (and profit!)
November 13, 2010 at 3:13 pm
Henry
You should be able to do this using the service http://www.futureme.org.
November 15, 2010 at 10:07 am
Jim
While it’s not quite the same, you could write the prediction down and mail it to yourself. Then you would have the date of the prediction, it would be validated by the postal service and then you could just open the envelope on the predetermined day. It would be more difficult to publicize the prediction though.
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Abodalrahman
By the way I just saw a vid that after much time spent explains the whole smbirpue crisis in CAPITALISTIC NON PARTISAN terms. Look up the youtube user informedtrades and then you might want to post it on various political vids like burning down the house . open some eyes. This is about money, not conspiracy, not politics, this is about money. There may be a money conspiracy, but it is not ideological, religious, political, racial, sexual or other. It’s about the golden rule.