Ander comments on Separating the roles of theory and direct empirical evidence in belief formation: the examples of minimum wage and anthropogenic global warming - Less Wrong

24 Post author: VipulNaik 25 June 2014 09:47PM

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Comment author: Ander 26 June 2014 12:11:25AM 1 point [-]

Excellent post!

Regarding ways that the questions might be disanalogous: For temperature data, I don't think that many people would question the data, average temperatures seem like good, hard facts to me. But some people might question unemployment data that they were presented with, stating that the measure of unemployment is flawed because it only measures people actively looking for work who are still eligible to receive unemployment. Some people 'fall off' and just become long term unemployed that no longer get counted in the statistics.

Perhaps you might note that some measure of 'percentage of population that is employed (adjusting for demographics changes)' would work better as the 'data' for some people?

Also, the post made me realize that in both of these two cases, the belief that I actually have (agree with both hypotheses), were formed due to the theory, and not due to looking at any empirical data. That is, when I hear empirical data in support of climate change, I think: 'well, obviously!', not 'here is the data that should be strengthening my belief in climate change'. I also realize that I haven't investigated and seen any data either way regarding whether minimum wages really do increase unemployment or not, and maybe I should do that.

Comment author: satt 26 June 2014 12:45:33AM 5 points [-]

For temperature data, I don't think that many people would question the data, average temperatures seem like good, hard facts to me.

In my experience a non-negligible number of people do take issue with the relevant temperature data, although I have no good hard numbers on this. (Probably no one does, given the difficulty of taking a representative sample of people who dispute the occurrence/magnitude of AGW.)

Comment author: brazil84 29 June 2014 04:49:21PM 1 point [-]

In my experience a non-negligible number of people do take issue with the relevant temperature data,

I think it's significant that of the well-known surface temperature indices, there is one -- GISS -- which has the highest recent temperatures. AFAIK, the GISS index is put together the authority of James Hansen who is pretty well known for his advocacy on the warmist side of the debate.

Comment author: satt 30 June 2014 08:24:49PM *  0 points [-]

I think it's significant that of the well-known surface temperature indices, there is one -- GISS -- which has the highest recent temperatures.

For the purpose of assessing the rate of global warming, whether a temperature index has the highest recent temperatures is less important than whether it has the highest difference between more recent temperatures and less recent temperatures.

AFAIK, the GISS index is put together the authority of James Hansen who is pretty well known for his advocacy on the warmist side of the debate.

The code for generating the GISS index is available online, as is a more user-friendly reimplementation of the GISS algorithm. So it should be possible to independently reproduce the GISS index oneself without relying on "the authority of James Hansen".

[Edit, 27 hours later: not really sure why someone's downvoted me for pointing these things out.]

Comment author: brazil84 01 July 2014 12:53:22AM 1 point [-]

For the purpose of assessing the rate of global warming, whether a temperature index has the highest recent temperatures is less important than whether it has the highest difference between more recent temperatures and less recent temperatures.

I believe that GISS also wins by that standard.

So it should be possible to independently reproduce the GISS index oneself without relying on "the authority of James Hansen".

Evidently, when creating a temperature index, judgments must be made about what data to use; how to crunch the numbers; and so on. Presumably that's why the leading temperature indices don't all agree. In the case of GISS, those judgments seem to have been made in such a way as to favor the warmist side of things. I strongly suspect this is the result of some kind of bias.

Comment author: Eugine_Nier 26 June 2014 02:26:04AM *  -2 points [-]

For temperature data, I don't think that many people would question the data, average temperatures seem like good, hard facts to me.

Not really. The problem is we don't have uniformly spaced weather stations all over the earth. Furthermore the locations of the stations we do have tend to change over the time period of interest. (The various proxies suffer from similar problems.) Thus it's necessary to apply weights to the data we do have to correct for this. Unfortunately, the weights are semi-arbitrary in practice and as we learned from the leaked climategate e-mails frequently have the warming built in.

That is, when I hear empirical data in support of climate change, I think: 'well, obviously!', not 'here is the data that should be strengthening my belief in climate change'.

What's your reaction to the data that shows a lack of warming over the past 17-years?

Comment author: bramflakes 26 June 2014 10:21:28AM 5 points [-]

What's your reaction to the data that shows a lack of warming over the past 17-years?

Nothing, because you can make any trend in a noisy dataset vanish by looking at a carefully-chosen small slice. El Niño peaked in 1998, the subsequent temperatures look flatter in comparison. Yawn.

Zoom out, the trend is clear.

Comment author: brazil84 29 June 2014 04:56:12PM 3 points [-]

What's your reaction to the data that shows a lack of warming over the past 17-years?

My main issue with it is that the people on the warmist side of the debate completely failed to predict it. Which is pretty good evidence that their thinking and their computer models are wrong. And yet, as far as they know, they continue to insist that their thinking and computer models are fundamentally sound. It seems to me like a class case of groupthink, self-serving bias, etc.