Tuesday, 11 June 2013
Saturday, 8 June 2013
Jason Malloy has been working on an interesting question, which is to determine at whether there is a clear gap in ability between black and white three year old children in America.
Some years ago there was much talk in Britain about tests which found that all racial groups began schooling at age 5 with identical “school readiness” results, but then progressively diverged as the years went by, strongly suggesting that schools were failing to teach British black children properly. I was never able to get to the bottom of what these tests were, and what range of skills they covered, and whether there were ceiling effects on the tests, but it was clear that pre-school intelligence testing results would cast light on whether children of different genetic backgrounds really started school with the same level of ability.
Malloy found 29 usable studies containing 35 different samples of children born between 1936 and 2000. There is IQ data for 2569 black children and 2762 white children, age 3
“A majority of these samples contain control groups of whites who were tested at similar times, and under similar conditions. When we compare the 20 samples with both blacks and whites, we get a difference of almost exactly 1 standard deviation: the black IQ is 85.4 and the white IQ is 100.8 (15.4 points/1.03σ).”
The figure shows the studies plotted out by year.
There is no particular trend (one early outlier study was excluded) and the pre-school intelligence gap looks pretty solid. The next post will discuss measurement issues. The predictive power of intelligence tests increase with subject age. Conventionally 7 years gives the first reliable indication of adult intelligence. 11 years is far better, but there is still more maturation to take place.
One more post to follow on this topic.
Friday, 7 June 2013
I have been reading my favourite blogs for years, without paying a penny for the privilege. The material was there, free, so I just read it. When some of my much-visited bloggers admitted they were facing destitution, I sent them some dollars every now and then. Life being what it is, I only did that when they reminded me that they could not continue writing without some income to support them. It was hit and miss. One day, reading Steve Sailer’s blog, I noticed a little ”Flattr” button at the end of each post.
flattr.com is a way of making social micro-donations. You set aside a fixed sum which will be distributed each month according to which blogs you think deserve support. The more you flatter different writers by clicking on their “flattr” buttons the more finely the donations are distributed, but they never exceed your maximum monthly sum. Think of it as a way of paying to read a newspaper, but ensuring that your payment goes to those columnists whose writings you most value, and to no-one else.
And now, back to the program.
ORIGINAL PAPER: How clever were the Victorians? A comment on Woodley et al. (2013) by Elijah L. Armstrong
Thursday, 6 June 2013
"Unfortunately, there is no good way to compare the results across computers. For example, "suppression" is weaker at low contrast, so somebody will have a weaker suppression looking at the video in a bright room than in a dark environment. Also the actual monitor frame rate will make a big difference. What can be compared is if two people look at the video under same conditions.
So, this is why you will need a friend. However, the results could potentially damage the friendship. I leave that dilemma to you.
Wednesday, 5 June 2013
Here at Psychological Comments we try to be more cognitively demanding. Your pronunciation of words is of marginal interest. Your reaction times, on the other hand, have some predictive value, so we tend to pore over those to test the quality of our readers. HBDchick is in pole position on this measure, and you are encouraged to test your own.
However, why not test yourself on something very closely related to intelligence, and something profoundly human: your vocabulary? Sure, you will be doing an intelligence test, but why not? The link is below
A bold reader, Elijah Armstrong is in pole position on this one with 32,800 words.
Best of all, this test requires the testee to be honest. You can make the number up by pretending to know the words offered up to you, but in that case you would be missing the point, and failing to understand yourself.
No such problem would ever afflict readers of this blog.
A very good morning to you all.