Author's words create "fingerprint"

Based on writing styles of Thomas Hardy, D.H. Lawrence and Herman Melville, physicists have developed a formula to detect author's literary "fingerprints". A new concept from a group of Swedish physicists from Umee University uses the frequency with which authors use new words in their work to discern distinct patterns in authors' written styles.
For more than 75 years, George Kingsley Zipf's maxim suggested a universal pattern for the frequency of new words used by authors. Zipf's law suggests that the frequency ranking of a word is inversely proportional to its occurrence. New research suggests, however, that the truth behind word frequency is less universal than Zipf asserted, and is linked more with the author's linguistic ability than any linguistic rule.
Experts first found that the occurence of new words in texts by Hardy, Lawrence and Melville did begin to drop off as their book got longer. Their evidence also shows , however, that rate of unique word drop- off varies for various authors and is consistent across entire works of any one of the authors analyzed. The authors all had unique word-frequency "fingerprints". Researchers are now pondering the idea of a 'meta-book' - a code for each author which could represent their entire work.