Ok, FYI, if you see the words “appears to be” and “if” in my sentences, it means I am acknowledging the ambiguity. If you do not want to annoy me, please wait until I’m using words like “definitely” and “when” or direct your “could not resist” comments at someone else.
If you want to discuss how we may determine the probability of a consistent and continuing downward trend, that would be constructive and I’d be very interested. Please do not waste my time by pointing out the obvious.
If you want to discuss how we may determine the probability of a consistent and continuing downward trend, that would be constructive and I’d be very interested. Please do not waste my time by pointing out the obvious.
(First of all, as I might have already mentioned, I don’t think that the average of (IQ − 132) over all readers is a terribly interesting metric; the total number of active contributors with IQ above 132 or something like that might be better.)
I’d guess that the decline in average IQ is mostly due to lower-IQ people arriving rather than to higher-IQ people leaving (EDIT: applying the intraocular trauma test to this graph appears to confirm that), and the population growth appears to have tapered off (there were fewer respondents in the 2012 survey than in the 2011 one, even though the 2011 one was open for longer). I’d guess the average IQ of readers is decreasing with time as a reversed logistic function, but we’d have to fit a four-parameter curve to three data points to test that.
the total number of active contributors with IQ above 132 or something like that might be better
Actually, a similar concern was brought up in response to my IQ Accuracy comment and Vaniver discovered that the average IQs of the active members and lurkers was almost exactly the same:
165 out of 549 responses without reported positive karma (30%) self-reported an IQ score; the average response was 138.44.
181 out of 518 responses with reported positive karma (34%) self-reported an IQ score; the average response was 138.25.
We could separate the lurkers from the active members and do the analysis again, but I’m not sure it would be worth the effort as it looks to me like active members and lurkers are giving similar answers. If you’d like to do that, I’d certainly be interested in any surprises you uncover, but I don’t expect it to be worthwhile enough to do it myself.
I’d guess that the decline in average IQ is mostly due to lower-IQ people arriving rather than to higher-IQ people leaving (EDIT: applying the intraocular trauma test to this graph appears to confirm that)
The sample set for the highest IQ groups is, of course, rather small, but what’s been happening with the highest IQ groups is not encouraging. The specific graph in question (although I very much doubt that Gwern would intend to make that graph misleading in any way) is just not designed to clearly illustrate that particular aspect of the results visually.
Here are a few things you wouldn’t guess without looking at the numbers:
Exceptionally gifted people used to be 18% of the IQ respondents. Now they are 6%.
The total number of highly and exceptionally gifted respondents decreased in 2012, while normal and moderately gifted respondents increased.
Ok, FYI, if you see the words “appears to be” and “if” in my sentences, it means I am acknowledging the ambiguity. If you do not want to annoy me, please wait until I’m using words like “definitely” and “when” or direct your “could not resist” comments at someone else.
If you want to discuss how we may determine the probability of a consistent and continuing downward trend, that would be constructive and I’d be very interested. Please do not waste my time by pointing out the obvious.
(First of all, as I might have already mentioned, I don’t think that the average of (IQ − 132) over all readers is a terribly interesting metric; the total number of active contributors with IQ above 132 or something like that might be better.)
I’d guess that the decline in average IQ is mostly due to lower-IQ people arriving rather than to higher-IQ people leaving (EDIT: applying the intraocular trauma test to this graph appears to confirm that), and the population growth appears to have tapered off (there were fewer respondents in the 2012 survey than in the 2011 one, even though the 2011 one was open for longer). I’d guess the average IQ of readers is decreasing with time as a reversed logistic function, but we’d have to fit a four-parameter curve to three data points to test that.
Actually, a similar concern was brought up in response to my IQ Accuracy comment and Vaniver discovered that the average IQs of the active members and lurkers was almost exactly the same:
We could separate the lurkers from the active members and do the analysis again, but I’m not sure it would be worth the effort as it looks to me like active members and lurkers are giving similar answers. If you’d like to do that, I’d certainly be interested in any surprises you uncover, but I don’t expect it to be worthwhile enough to do it myself.
The sample set for the highest IQ groups is, of course, rather small, but what’s been happening with the highest IQ groups is not encouraging. The specific graph in question (although I very much doubt that Gwern would intend to make that graph misleading in any way) is just not designed to clearly illustrate that particular aspect of the results visually.
Here are a few things you wouldn’t guess without looking at the numbers:
Exceptionally gifted people used to be 18% of the IQ respondents. Now they are 6%.
The total number of highly and exceptionally gifted respondents decreased in 2012, while normal and moderately gifted respondents increased.
I did some analysis here