Expertise – a matter of practice?

One of the founding fathers of the study of intelligence, Francis Galton, was a very interesting and colorful figure.

Galton, who was Charles Darwin's cousin, wanted to implement Darwin's theories on humans, and to improve humankind by mating between people with the best mental, moral and physical skills.  Nowadays such an idea sounds shocking, but in the nineteenth century it might have sounded reasonable. Galton looked into families of people who were considered wise and successful, and saw that the closer the  blood relation to a wise person is,   the better are the chances of this person's relative to be also wise.  Galton deduced that "wisdom" (the term "intelligence" didn't exist then) is, at least partly, hereditary.  Galton studied children who were adopted by the Pope, to see what is more influential: genetics (which was "weak" in these children's case) or environment (an environment rich with stimuli at the Pope's surrounding).  He found that there is an interaction between genetics and environment, but genetics is stronger than environment.

Apropos Galton, he probably was the only psychologist in history who was paid by his experiment participants for this privilege!  Galton studied other things, like women's attractiveness in different parts of England, and the relationship between prayers for the wellbeing of kings and their life expectancy (he found there was no relationship…).

While Galton worked in the 19^th century, John Watson, one of the founding fathers of Behaviorism, wrote in 1930: " Give me a dozen healthy infants, well-formed, and my own specified world to bring them up in and I'll guarantee to take any one at random and train him to become any type of specialist I might select—doctor, lawyer, artist, merchant-chief and, yes, even beggar-man and thief, regardless of his talents…" 

Anders Ericsson sided with Watson.  In the 1990's he interviewed violinists and pianists and found that the violinists and pianists who were considered to be the best of their kind accumulated more than 10000 hours of practice by age 20.  Amateur violinists accumulated about 5000 hours of practice and amateur pianists – about 2000 hours of practice by age 20.  Ericsson argued that  genes may contribute to individual differences in people's willingness to engage in deliberate practice over a long period of time, and thus may indirectly contribute to individual differences in performance, but  he explicitly rejected the view that innate ability can account for why some people become experts and others fail to do so.  He argued that expert's performance reflects a long period of practice more than innate ability or talent.

It's easy to see why Ericsson's 1993 paper on this subject became a hit and was cited more than a thousand times.

Clearly, many people who want to become experts – as violinists, physicists, athletes and so on – don't make it despite investing hours of practice and effort.

In this paper:

Deliberate practice: Is that all it takes to become an expert?

David Z. Hambrick ,  Frederick L. Oswald , Erik M. Altmann , Elizabeth J. Meinz, Fernand Gobet , Guillermo Campitelli .  Intelligence 45 (2014) 34–45

https://www.msu.edu/~ema/HambrickEtAl.pdf

the researchers asked: is practice enough to become an expert?  Can  individual differences in performance be explained mostly by individual differences in practice hours?

They studied these questions by analyzing research done in two areas of expertise:  chess and music.

The chess studies included players who were rated in the international rating, the Elo, were members of prestigious chess clubs, participated  in national chess programs and so on.  These players gave information about the age they started playing and estimated the number of practice hours they had each day during their training years.  The authors found that practice explained 34% of the variance in chess performance (the player's Elo rating).  34% is a significant amount, but practice did not explain everything!  They also found, that some people needed much less practice to reach an excellent level of performance in chess.  Some expert chess players needed 3 times more hours of practice than other expert chess players.  Some expert chess players needed less practice hours than intermediate chess players.  Some intermediate chess players practiced more than expert chess players.

The paper describes the story of the Polgár sisters who, beginning at a young age, received several hours of chess instruction every day from chess grandmasters and their father, a chess teacher and author of several chess books.  The sisters differed both in the highest rating they achieved and in the amount of practice they accumulated to reach that rating. One sister's peak rating was 2735 in an estimated 59,904 h of practice, whereas another sister's was 2577  in an estimated 79,248 h of practice.  The two sisters who became grandmasters had accumulated a great deal more practice by the time they reached their peak rating than had the eight grandmasters who reached top-ten in the world with a mean of about 14000 hours of practice. 

 

Deliberate practice is clearly not sufficient to account for individual differences in chess performance.   What else explains chess performance? What about excellence in music?    These topics will be discussed in the next post.