Few subjects arouse as much ire as national IQs. Questions are asked about the cultural appropriateness of the tests, whether they have sufficient scope to assess the different talents of racial and cultural groups, the representativeness and size of the samples, and even whether those results are reported correctly.
National scholastic achievements, on the other hand, are greeted with widespread publicity, discussed anxiously in government and educational circles, and sometimes rather naively accepted as an unerring measure of a nation’s educational system. In some ways this is understandable, because PISA and similar studies are well-funded, are global in scope, and repeated at regular intervals, allowing progress to be monitored. Yes, every test can be gamed, and national results vary considerably in coverage, representativeness, and probably also in levels of cheating. However, these are matters for the sort of people who read the supplementary annexes, and persons of that sort cannot be considered normal.
Every test, either “school near” as those designed for PISA or “school far” as designed for intelligence testing, are subject to the same concerns about sampling, measurement invariance, individual item analysis, and the appropriateness of summary statistics. Why the difference in public response to these two different points on the assessment spectrum? Perhaps it is as simple as noting that in scholastic attainment there is always room to do better (or to blame the quality of schooling) whereas in intelligence testing there is an implication of an immutable restriction, unfairly revealed by tricky questions of doubtful validity.
Perhaps it is a matter of publicity. PISA has the money for brochures, briefing papers, press conferences, meetings with government officials. Richard Lynn put his list together in his study, and came up with results that many were happy to bury.
Now we have David Becker taking over the database, and doing the whole thing again. Here is the 3rd major iteration of his revision. He tells me:
In the last six months, I have been able to increase the number of sources used from 253 to 357 and the number of nations from 92 to 123, and also to make many improvements in the methods. At present, the database contains samples to a total of 550,492 individuals.
Here is a diagram showing the relationship between the newly established IQ values (David Becker, X axis) to those of Lynn and Vanhanen on Y axis (L & V).
The correlation is .90 for 305 Comparisons. The average of the IQ variations is only 1.07 with a standard deviation of 5.86. This means that around 75 % of the new IQ measurements do not deviate more than 5.86 points from the original measurements. A deliberate manipulation of the figures by Lynn and Vanhanen, as the two scientists have often been accused of, I cannot confirm with the best will. More still, looking at the polygono shuffle (dotted) in the diagram, it can be seen that, compared to me, Lynn and Vanhanen showed higher values, especially in the IQ-Weak African and IQ-Strong Northeast Asian samples. (My note: slightly over-estimated African and East Asian intelligence).
However, it was the hypothesis that Lynn and Vanhanen wanted to test that countries with higher IQ would also have greater economic strength (GDP / head). However, these countries are, in particular, in the range from 95 to 105. Japan as a country in North-East Asia with the highest GDP / head of 41,300 \$ and a national IQ of 104-107, for example, is far below the US with a GDP / head of \$ 57,400 and a national IQ of 97-99. If Lynn and Vanhanen were deliberately increasing North East Asian IQs, then this would have reduced the support for their own hypothesis
In PISA style, here are the highlights:
1. The population-weighted cross-national mean IQ-score is 89.03, with SD of 12.89, for 123 nations. There are roughly 550,000 individuals in the included samples.
2. The countries of Latvia and Belarus are new in the dataset and are included in the geographic means, but Latvia still has poor data quality.
3. At the level of records (source), my re-estimated (DB) and Richard’s original (L&V) data give:
DB: M=85.58; SD=13.73; N=358
L&V: M=85.36; SD=12.69; N=315
They are highly similar. The mean difference was estimated for 314 records as only 1.06, with a SD of 5.84. 75% of the re-estimated IQs are within this SD.
4. But I would also emphasize that there are some other re-estimated scores which more than 15 IQ-scores away from Richard’s and the reason for this has to be determined urgently. Especially scores from Coloured Progressive Matrices (the new ones) are sometimes implausible.
So, it is overall important for me to say that this is a work in progress and the dataset is more suitable to find global patterns rather than the exact IQs of single nations.
In the spirit of open science, here is Becker’s work in progress for you to look through.
Here is the entire spreadsheet
Read the Manual 1.1 to get an understanding of the basic terms and categories.
On the spreadsheet the simplest summary is in “Favorites” and there is more background material in “Collection”. The nitty-gritty is in “Calculations” but there is even more detail in the further tabs.
For users who want quick access to IQ lists the table “FAVORITES” is recommended. It contains the final estimated national IQ-scores without additional information.National IQ-scores in column D (IQ(DB)) based solely on data, repeatedly checked and partly recalculated by David Becker. For these scores the highest possible amount of additional information is provided. Therefore, these scores are best suited to those who want to focus on rechecked and data from transparent and highly standardized methods.
National IQ-scores in column E (IQ(L&V)) were taken from the latest version of the dataset from Lynn and Vanhanen (2012, Table 2.1). All necessary corrections were done by Lynn & Vanhanen without revision by David Becker. Therefore, these scores are best suited to those who prefer to use original instead of revisited data, and the highest possible number of sources per nation.
National IQ-scores in column F (M(DB,L&V)) were calculated by unweighted means of column D and E. Therefore, these scores are best suited to those who prefer to use original and revisited data combined.
National IQ-scores in column G (IQ(L&Vo)) were calculated by David Becker as means from every single source which was not revisited. All necessary corrections were done by Lynn and Vanhanen without revision by David Becker.
National IQ-scores in column H (M(DB,L&Vo)) were calculated as means from data in columns D and G, weighted by number of sources. If National IQ-scores from columd D not given, national IQ-scores from column E used. For these scores the highest possible number of sources was included in the table “RECORDS”. Therefore, these scores are best suited to those who focus on a compromise between quality and quantity.
The tables “COLLECTION” and “RECORDS” contain IQ-estimates at the source-level and background material for calculations and corrections. A more differentiated view in national IQ-scores can be found in table “NATIONAL” including separated IQ-scores by type of test. Here, revisited and original data were given and thus recommended for users who want to look beyond the mere national IQ-scores.
There are three maps: Becker’s version; Lynn and Vanhananen; composite. It is premature to create maps until one is sure about all the data points, so accept this as an overview of the general trend, and no more than that.
In conclusion, this work has progressed far but there is still work to be done: you must note the cases of discrepancies which need to be tracked down and resolved. In terms of future developments of the database, there are many more studies to be added.
However, once all this has been said, it has to be recognized that this is the largest and most carefully described collection of the world’s intelligence results.