I can't say there isn't money to be made in ad revenue or personal information by setting up websites that collect the two, and it seems like most IQ test websites are meant to do precisely that.
Anything that's given away for free (especially an IQ test) is probably not going to be as accurate or precise (more on the difference in a moment) as something you pay for. But hey, since this is a blog about a book that discusses intelligence, why not try one out?
About ten months ago, I did precisely that. The test I took was from
http://iqtest.com and at that time my score was 137. Here's a screen cap I did of the email notice at that time.:
I wish I still had the login, but I don't plan on purchasing the full report anyhow. At the time I took the test, I had not yet read "The Bell Curve" so I didn't really think as deeply about the result as I would today. Now that I've taken an exam from IQTest again, this was my result:
Apparently not much has changed. I can now safely say that the quiz available at
http://IQTest.com/ is
precise, but I can't make a clear call about just how
accurate it is. To understand the difference, take a look at the image below:
Notice that the average of all the points in the first target are pretty centered. The second one is off-center, but all of them land in precisely the same area. Finally the third image features precise points that are dead center.
Since both my results are in the upper 130's, I feel pretty confident that the test is precise. People with a stable IQ will score roughly the same every time. However, I can't say for sure whether or not it is truly an accurate quiz. Does it overstate what my real IQ score would be? Is it like a scale that adds more weight to every object you place upon it because you adjusted it to do so?
I won't know for sure until I take a "professional" IQ test sometime in the future. Perhaps I'll have to fork over some time and money to MENSA to have that determined.
For now, it looks like I'm in the top 1% according to the standard bell curve score distribution:
So for future reference, anyone wondering what my score is can safely assume it's roughly 135 or higher. At least until I take a professional test...