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MichaelAnissimov comments on Assessing Kurzweil: the results - Less Wrong

42 Post author: Stuart_Armstrong 16 January 2013 04:51PM

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Comment author: MichaelAnissimov 16 January 2013 06:33:43PM 0 points [-]

Which predictions are very obvious?

Comment author: EricHerboso 22 January 2013 06:59:32PM 3 points [-]

As a (perhaps) trivial example, consider the pair of predictions:

  • "Intelligent roads are in use, primarily for long-distance travel."
  • "Local roads, though, are still predominantly conventional."

As one of the people who participated in this study, I marked the first as false and the second as true. Yet the second "true" prediction seems like it is only trivially true. (Or perhaps not; I might be suffering from hindsight bias here.)

Comment author: V_V 30 January 2013 01:43:52PM 0 points [-]

But why was this counted as two separate predictions? The two statements are even syntactically linked by the "though" conjunction.

Comment author: TheOtherDave 30 January 2013 02:56:08PM *  2 points [-]

Why oughtn't it be? The construction "A, though B" is an independent assertion of A and B. Syntactic linkage is not enough to establish contingency.

It is not like "A, because B" for example, where it's arguably unfair if B and A are both false to count it as two failures... in that case, the claim of A can be seen as contingent on the claim of B, and not independent.

To put this differently, "A, though B" makes the following claims:
A
B
You might (mistakenly) expect -B given A, which is why I mention B explicitly.

Whereas "A, because B" makes the following claims:
B
If B, then A

If A happens in the first case, the first claim is correct. If B happens, the second is correct. If both happen, both claims are correct.

If A happens in the first case but B doesn't, the first claim is correct and the second claim is unevaluatable.

(I suppose one could argue that the second case implicitly claims "if -B, then -A" as well... "because" is somewhat ambiguous in English.)

Comment author: Kindly 30 January 2013 03:06:32PM 2 points [-]

This is only a problem because we haven't been comparing the relative "difficulty" of predictions. Admittedly this is hard to do; but I think it's clear that:

  1. "Intelligent roads are in use, primarily for long-distance travel." is a much more ambitious prediction than "Local roads, though, are still predominantly conventional."

  2. Treating the two statements as a single prediction "A, though B" is more ambitious than either, and should be worth as many points as the two of them combined.

Moreover, any partial credit for "A, though B" would take into account that B happened though A didn't. Or rather, a prediction that intelligent roads are only somewhat in use should receive more credit than a prediction that intelligent roads are ubiquitous.

Comment author: TheOtherDave 30 January 2013 05:33:19PM 0 points [-]

Agreed that understanding the "difficulty" of a prediction is key if we're going to evaluate the reliability of a predictor in a useful way.

Comment author: EricHerboso 31 January 2013 08:47:05PM 1 point [-]

In the future, we might distinguish "difficult" predictions from trivial ones by seeing if the predictions are unlike the predictions made by others at the same time. This is easy to do if we evaluate contemporary predictions.

But I have no idea how to accomplish this when looking back on past predictions. I can't help but to feel that some of Kurzweil's predictions are trivial, yet how can we tell for sure?

Comment author: V_V 30 January 2013 05:13:22PM *  0 points [-]

Well, if you analyze the statements in terms of prepositional logic, then all the English language conjunctions "and", "but", "though", etc. map to the only type of logical conjunction ∧.

But natural language is richer than (directly mapped) prepositional logic. I interpret the statement "Local roads, though, are still predominantly conventional." as a clarification of "Intelligent roads are in use, primarily for long-distance travel.".

Formally, if you just claim:
"Intelligent roads are in use, primarily for long-distance travel."
it is equivalent to:
"Intelligent roads are in use, primarily for long-distance travel." ∧ ( "Local roads are still predominantly conventional" ∨ ¬"Local roads are still predominantly conventional" )
which is different from
"Intelligent roads are in use, primarily for long-distance travel." ∧ "Local roads are still predominantly conventional"

However, we can assume that if you claim:
"Intelligent roads are in use, primarily for long-distance travel."
you also wanted to communicate that
"Local roads are still predominantly conventional"
not that you are undecided between
"Local roads are still predominantly conventional", ¬"Local roads are still predominantly conventional"
otherwise you would have probably stated that explicitely.

Therefore, the information content of:
"Intelligent roads are in use, primarily for long-distance travel."
and:
"Intelligent roads are in use, primarily for long-distance travel. Local roads, though, are still predominantly conventional."
is rougly the same.