Quote from: daniel_von_flanagan on December 16, 2008, 04:18:36 PM

Quote from: jacobisrael on December 16, 2008, 04:10:44 PM

Are you sure that you've read that TIMSS study about our 12th grade scores?  The methodology for picking the cohorts was the same in both the 8th and 12th grade


They nevertheless are not the same cohort.  The reason is that the 8th graders were in 8th grade that year, and the 12th graders were in 12th grade that year.  In many cases, when the 12th graders were in middle school they had different curricula than the 8th graders did when they were in middle school.

This is not complicated stuff.  Really. - DvF

Now I understand your point.  Thank you very much for clarifying it.

Please point me to the evidence that there was a national, across the board, change in the curricula between 1991 and 1995 if you believe this to be a possible explanation.  Can the same be said for all of the other countries which took TIMSS?

If anything DID change (and this is not to even hint that anything changed) then would you not agree that our change was clearly for the worse and theirs was for the better?

Austria's scores were an exception in Europe, as they followed a similar pattern to the US, only more extreme.  While our boys' scores decreased 56 points, theirs decreased 85 points.  And while our girls' scores decreased 104 points, their decreased 137 points.  So while just the increase in the gender gap was 48 points in the US, it was 52 points in Austria.  This is not an insignificant decrease, since the standard deviation for US girls was 53, making this 0.91 S.D.  Since the standard deviation for Austrian girls was larger, at 71, the increase in their gender gap was smaller, at 0.73 S.D.

But there was already an 8 point gender gap in Austrian 8th graders, making their total gender gap by 12th grade 0.85 S.D.

I'm not clear on how changes in the curricula could have affected any of this.  I don't even know what can be changed to cause such huge race and sex gaps, or to make them bigger or smaller.  So it would be greatly appreciated if you'd provide an example.

Actually, I can think of one small example.  Not too long ago, Chinese educators were invited to visit the US to study our education system.  They asked many great questions, and my input was they should implement calculus in high school as Japan had.  They did that, and now 95% of Chinese students complete calculus before they graduate from high school.

Pretty smart, eh?  What have our educators done lately to top that?

I've tried to stay out of this one as DvF has done an admirable job of presenting the points I wanted to make. However, please allow me to add my two cents' worth. First, you are comparing different systems that do different things. You are comparisons are being made between countries where there are NATIONAL curricula, those where there are STATE curricula, and at least one where it is a hodgepodge of STATE and LOCAL curricula. So, we are comparing apples to oranges to pears.


The entire PURPOSE of an international study IS to compare different education systems to each other, which is exactly what TIMSS does.Just like the entire PURPOSE of a national study like NAEP is to make state to state comparisons to see what works and what fails. It�s not BAD to make international and national comparisons, it�s GOOD.

Also, we need to address the differences in systemic student handling. In the US, we send the vast majority of our students to high school; other countries reverse this entirely. Thus, the 12th-grade cohorts aren't even comparable between countries, even though they are presented as such by the media (among many others). While the 4th-grade cohorts may be similar, there is even some question about the comparing 8th-grade cohorts by some. For the two reasons above, I don't believe TIMSS is as valid an indicator of differences between national systems as its exhorters proclaim.


This is patently false.Fortunately, it�s PROVABLY false.Our OWN data from NCES claims that 74% of American 18 year olds graduate from high school, compared to more than 90% in most industrialized nations:




The reason nobody has ever posted a cite which disputes that is that there is no cite, AND TIMSS disputes it in a different direction, claiming that they found that only 63% of American students are in their �TCI�, compared to 82% in Switzerland, 84% in Norway, 75% in Germany, 88% in Slovenia, etc.




They found that 1,245,594 American children of high school graduation age, 67% of that population, weren�t even IN high school, and thus were never included in our already LOW TIMSS scores.If the worst students were the ones who weren�t in high school, can you even IMAGINE how low our scores would have been had they been INCLUDED?If this is the reason you don�t �believe TIMSS is as valid an indicator of differences between national systems as its exhorters proclaim�, you need to use your new-found knowledge to go back and rethink your position.

Finally, a word about why DvF keeps trying to get you to understand why comparing cohorts is important. Many states have been adjusting/rewriting their regulations (Pennsylvania), their state-mandated tests (Ohio), and their state-mandated curricula (Georgia) for the past decade or more. In mathematics, the National Council of Teachers of Mathematics (NCTM) issued its first set of standards on K-12 mathematics in 1989. This was the first step in the reform process, and several states began the process of reforming state curricula in the early 1990s. Others waited longer. However, the process is not an instantaneous one. As an example, Georgia instituted the Georgia Performance Standards (GPS) in 2003 or 2004. The standards still aren't fully implemented throughout the schools yet, and they won't be for two more years. So, yes, cohort matters, and we need to deal with the data that way. The only fair comparisons about gains and losses in the report's 12th-grade cohort would be to take the 2007 report's 12th-graders and compare that gap (assuming all the other confounding variables didn't exist) to the gap found in the 2003 report's 8th-graders and to the gap found in 1999 report's 4th-graders. This assumes that the tests across that EIGHT-YEAR SPREAD are equivalent.


None of which is relevant.The entire POINT of TIMSS is to make international comparisons, not state to state comparisons.Your idea that something in our education system was the �first step in the reform process� is the same thing educators have been mimicking for years, and none of it ever worked.Furthermore, all American parents I know believe that every single one of these so-called �reforms� only brought us back quicker to the stone age and improved nothing.


TIMSS also proves how SAT scores have been politicized, feminized, manipulated, and watered down to the point they�re no longer credible.



�For another view of it, let's look at your classroom. In a large lecture class, grades tend to be distributed "normally". This being the case, "curving" (with its true meaning) would assign Cs to the 68% of the students whose scores are within 1 SD of the mean. So, let's assume that the mean on Test 1 was 75 with a standard deviation of 8. So, any student with a score between 67 and 83, inclusive, should get a C. However, Susie with her 81 and Johnny with his 69 both got Cs! Is the difference significant? We don't know until we run tests on the scores. Even though the difference is 12 points (which is 1.5 SD), it is likely that this difference is NOT "statistically significant" at any appreciable level. To constantly quote raw numbers with no test results is worthless and misleading. Even those with an agenda don't do this because they know they will be accused of trying to bamboozle the people reading the report.�


You complain about referring to different cohorts, then launch into a comparison between a large lecture room and an international study of hundreds of thousands of students.

You CANNOT compare these and make any sense out of it. You literally can�t adjust for guesses on multiple choice questions in the �large� lecture hall, but you CAN when there are hundreds of thousands of students taking the SAME test in their own languages.Do you know what TIMSS is?Before you invite anyone to �take a statistics class� again, you ought to invite yourself to examine their methodology.You are as wrong about this as you are about �In the US, we send the vast majority of our students to high school�.



Quote from: daniel_von_flanagan on December 12, 2008, 04:00:59 AM

As for performance differences by race in the US, I would guess that the average African-American at New Trier High has better math scores than the average white student at Henry Ford High in Detroit. - DvF

Why would you believe that?

Because I've taught mathematics to minority students from good high schools, and to white kids from bad ones, and the former perform better than the latter in my experience.


Could you explain what you mean by that?

I think it is pretty self-explanatory.

Am I right in assuming you are jacobisrael under a new login name? � DvF



Reply #95 on: December 12, 2008, 01:47:20 AM �

Quote from: jacobisrael on December 12, 2008, 01:42:01 AM

Not every step along the way is necessarily cumulative, but it's also
not impossible that the total number of standard deviations of
separation between American black females in DC and boys in Norway is
a total of 14 to 18.5 standard deviations.

It is if we're assuming anything even remotely like a normal distribution.  Getting outside of three standard deviations is very unlikely (three-tenths of a percent); getting outside of 10 or 12 is a miracle of Biblical proportions.


12/23/2008 9:49:28 PM


So you don't believe Obama when he says his IQ is 132?

Great point.

In 2003, 3 African nations, Ghana, s. Africa, and Botswana participated in TIMSS physics.  The average score for the 5,150 students in Botswana who took the test was 443, seven of whom scored over 505, and none of whom scored over 549.  The average score for the 8,952 students in South Africa who took the test was 244, thirteen of whom scored over 447, and none of whom scored over 514.  So also in Ghana, where the average score for their 5,100 students was 239, seven of whom scored over 427, and none of whom scored over 514.

Conversely, the average score for the 6,018 students in Singapore was 579, eight of whom scored lower than 462, and none of whom scored lower than 423.  At best we can say that eight students in Singapore MAY have scored lower than SEVERAL of the thirteen highest scoring students in South Africa and SEVERAL of the seven highest scoring students in Ghana.  No student in Singapore scored 4 standard deviations higher than their mean, or 735, much less 5 standard deviations higher, at 774.

So needless to say, no student in Botswana, South Africa, nor Ghana ever scored four standard deviations higher, or 549, 514, or 489, respectively, either, much less five standard deviations higher, or 593, 581, or 551 respectively.  Such scores are in the range of the average for Taipei and Korea, whose IQs are in the range of 105 IQ points.  It simply boggles the imagination for us to be expected to believe that Obama was the ONE Kenyan in the entire world who scored not just one but TWO standard deviations higher than a place where NO Ghanan, Botswanan, or South African has ever ventured.  To claim that his IQ is 132 IQ points, yet another three standard deviations higher than the impossible, is the height of absurdity.  Yet that�s exactly the claim that his presidential campaign made and you should be embarrassed to the hilt to see so many of your fellow countrymen fall for this circus act.

The average IQ of Kenya is 71 IQ points, the same as for Ghana, and 1 point lower than both Botswana and South Africa, at 72 IQ points.  Out of 38 million Kenyans, do you know how many score more than 5 standard deviations higher than that?  Only 11 do, at an IQ of only 96 IQ points, four standard deviations higher than their mean, and NONE have an IQ higher than 101 IQ points, five standard deviations higher than the mean.  Obama�s not even a Kenyan.  He�s a mixed breed and most mixed breeds of most species are of lower quality and intelligence than the pure breeds (otherwise why don�t mules race in horse races)?

California voters consider affirmative action to be CHEATING, which is why we outlawed it with Proposition 209 which actually amended the state constitution for the express purpose of KILLING it.  Obama is clearly left over from those days.

Why not simply require him to take the normal IQ test which any dog catcher in the country has to take in order to qualify for his job?

You can bet that this would settle the matter once and for all.

Correction, Tues. Dec. 23, 2008: 7% of the population of Botswana are Whites who score similar to their brethren back in England at 545, meaning that the 93% who�re blacks scored 358.  Only seven black students from Botswana scored over 456 and none of them scored over 514.  Therefore, none of the lowest scoring eight students in Singapore who scored lower than 462 are likely to have scored lower than the seven top scoring black students from Botswana, meaning there was no overlap of test scores between Singapore and Botswana.



Quote from: polly_mer on Yesterday at 10:11:01 PM

[I know I will regret this, but I'm going to jump in here anyway]The ability to think logically, use references appropriately, and pick the right tool for the job means nothing in terms of success in school or life.

This is a breathtaking admission.

And of course you'll claim I'm singling you out simply because you're a "minority" [even though 52% of our population are women and only 48% men].

What you discard as irrelevant happens to be EXACTLY, *precisely*,  where the rubber meets the road.  Yet, you probably will never know that, and your cohorts will be groveling all over the floor to prove you right.

In a competitive "global economy", when you throw all that out, and our competitors don't, we're history, plain and simple.  That's not even economics 101.

However--that's not the original point, nor the original theory.  What you suggest for the reason for the gender gap between American girls and Norwegian boys being 3.6 S.D. is in my view only a partial explanation, if it's applicable at all.

But as an educator, you might have some insights here that might be valuable to our understanding our problem.  Do you believe this is the only explanation?  Do you believe that the only reason Norwegian boys scored so high is their "ability to think logically, use references appropriately, and pick the right tool for the job", whereas American girls don't?  Or can't?  Or don't want to?

Since you raise this theory, could you elaborate on it? Why do you believe this would be the case?  Do you believe this is the result of poor education policy on our part, or an innate ability in Norwegians?  Do you believe we can change our education policy to improve the situation, or do you believe we're doomed to oblivion?