Close your eyes and believe.

From Applying IQ to IQ: Selecting for smarts is important by Razib Khan.  

In various forms, standardized testing has been with us for 2,000 years. During the Han Dynasty a group of bureaucrats began to undergo examinations to vet their competency. This system of examinations became more formalized and elaborated in later dynasties. The rationale for these examinations was that those who rule should be inculcated in timeless values and exhibit intellectual abilities. 

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When examinations fell out of favor, as occurred during the Eastern Han, the Tang, and the Yuan, the consequences were inevitable. A coterie of great families, or ruling castes, came to dominate the administration, and unattached youth of talent were excluded and marginalized. The testing regime was uniformly disliked by the aristocrats because they already had power, connections, and polish. They perceived in themselves the right to rule. They required no test to validate their self-worth. For those born to rule, the memorization of ancient texts and the drafting of learned essays is tedious. But to the bright but unconnected, mental gymnastics are a chance to demonstrate their worthiness.

Sometimes the historical precedents are eerie. The Age of Confucian Rule recorded that there was a tacit understanding that there would be a ceiling on the number of officials who came out of Fujian. This southeastern coastal province brimmed with scholarly activity during this period, and it sent far too many candidates through the examination system for ruling elite comfort. The Song engaged in what we would call affirmative action to allow for the representation of Northern officials within the bureaucracy. 

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Tests are imperfect. But what is the alternative? Over the past few years graduate schools have been removing the GRE as a requirement for admission. What will the consequence be? If the history of China is any guide, those with connections and pedigree will benefit. Without a hard-to-fake entrance exam, recommendations from those you trust will loom large again. The abolition of the GRE will be a back door through which the “letter of introduction” returns. Who will be hurt by this? Who will benefit? There are many answers here, but one thing seems obvious: those without connections will suffer. International students. Those from working-class backgrounds. Non-traditional older students trying to turn their life around with the benefit of hindsight. When academics rely on networks of those they already know, the circle of inclusion will begin to narrow. Ironically, attempts to “foster inclusion” by removing standardized testing will inevitably constrict the space of those included. 

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In a strange denouement, the professional-managerial class of the United States, itself sorted through grades and standardized tests, has turned against these sorting tools of the institutions which provide them prestige and power. When scientists assert that the GRE does not predict success, they magically forget the ability of range restriction to constrain the predictive power of a variable. Believe it or not, taller basketball players are not the best basketball players in the NBA. That’s because NBA players are all already tall, more or less. The abolition of the GRE and marginalization of the SAT, amount to a massive natural experiment. These experiments are predicated on the idea that standardized testing is useless. No matter that in various forms this method has been around for 2,000 years, and we have evidence of the benefits and deficiencies of testing in the historical record. Close your eyes and believe.

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Meanwhile, the Chinese and other Asian nations continue to use standardized tests as a mechanism for admission and sorting. This does not guarantee better leaders necessarily, but it does mean that members of the professional class have all gone through the same mechanism of selection, and one which is relatively insulated from the impact of pedigree and connection, which otherwise loom large in many Asian societies. The fact of the importance of connections means that Asians understand the value and power of the “big test” which is blind to all the other “holistic” factors, which often smuggle privilege in through the back door. 

The next generation will be a test. Will America turn away from intelligence and aptitude testing to unleash untapped capital? Or will our society’s meliorist impulses only usher in a new era of cronyism and favoritism? History teaches us to anticipate the latter. But you never know until you run the experiment.