Classical composers’ key data are displayed as a heat map with the shape of a piano keyboard.
The top half of each note represents percentage of minor compositions in that key, and the
bottom half of each note corresponds to major compositions in that key.
The highest percentage for each composer is labeled. Each composer’s heat map is scaled the same (0 to 20%), so you can compare one composer to another.
The N-values next to the names show the number of compositions included in the database for that composer - these are not comprehensive lists! However, the samples sizes are large enough that the probability distributions should be at least reasonably accurate (to within a couple percent).
A few noteworthy trends pop out.
Beethoven, Haydn, and Mozart all show strong preferences for a specific key.
Other composers, particularly Dvorak, Brahms, and Mendelssohn, show less favoritism; these three had no keys associated with >10% of their compositions, with Brahms having the smallest standard deviation (2.14%).
All three composers whose most-used key was minor were from the Romantic era.
The least used key across the keyboard was g# minor, with Brahms using it most (in only 1.5% of his compositions).
Rachmaninoff was the only composer to produce more pieces in minor keys than major keys.
Haydn and Mozart most frequently wrote in major keys.
Finally, Tchaikovsky is the closest to the notion of an average composer; in other words,
his probability distribution most closely resembles the distribution created by averaging all
ten composers together.
