2/24/2022 – In this article, statistician Bruno Wiesend reports on a scientific controversy about a study on the "Influence of intelligence and practice on the development of skills". The author considers the results of the study to be wrong due to methodological errors. | Photo: Pixabay

3/20/2020 – Vaci, Gula, & Bilalić (2015) found that “the more able players deteriorated more quickly” after their peak, but that their decline started to stabilize earlier in middle adulthood. The authors claimed the validity of Simonton’s (1997) model of career trajectories for chess players, and highlighted the beneficial influence of tournament practice in old age. They doubted the appropriateness of the FIDE database for scientific studies, and instead recommended the German database. It is now shown why Vaci et al.’s model led to drastically incorrect results, and how it has to be changed to work correctly. Chess trajectories are characterized by a long plateau phase and a gradually increasing decline. Playing more or fewer games does not affect the rating in old age.