Lennon or McCartney? Machine learning used to work out which Beatle wrote which song

Paul McCartney must just have 'misremembered' his role in the song 'In My Life', AI concludes

Data scientists at Harvard and Dalhousie University in Canada have devised a machine learning system that, they say, can identify which member of the Beatles wrote which song.

The scientists trained the system on 70 songs from the Beatles back catalogue, enabling them to attribute particular songs with either John Lennon or Paul McCartney, where known, based on their musical styles, building up a ‘musical fingerprint' of each musician in the process. The fingerprint was, based on 137 unique musical patterns.

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These patterns include notes, chords and other musical flourishes that could be uniquely identified with either McCartney or Lennon. When tested against Beatles songs where the author is known, the system achieved an accuracy of 76 per cent.

The system was then set to the task of identifying eight particular songs or parts of songs recorded between 1962 and 1966 in which the authorship or dominant influence remains a subject of debate - not helped by conflicting accounts from the band's members over the years.

The scientists claim that the system identified authorship with 90 per cent certainty to the songs 'Ask Me Why', 'Do You Want to Know a Secret' and 'A Hard Day's Night', and was also able to identify between Lennon and McCartney for different parts of the same song.

For example, 'In My Life' was attributed with 81 per cent certainty to John Lennon - a song for which Lennon had written the lyrics, but which McCartney claimed to have written the music. However, the system attributed the song's middle-eight melody to McCartney.

"Breaking apart the song into the verse and bridge separately it is apparent that the verse is more consistent stylistically with Lennon's song writing," the authors wrote.

However, 'Baby's in Black', 'The Word' and 'From Me to You' were correlated with McCartney with up to 97 per cent certainty.

The scientists claim to have worked on the project for three years. The findings have been published in Harvard Data Science Review. The full paper can be read here.