Sybil Identification Mechanism for Fraudulent Document Detection Through a Cognitive Based Personal Encryption Key

An embodiment of the invention provides a method of monitoring for fraudulent activity where a key generating device generates a first key based on a writing profile of a user, and where the key indicates the writing style of the user. The generation of the key includes generating trait scores for writing style traits, where the writing style traits includes an agreeableness trait, a conscientiousness trait, an extraversion trait, an emotional range trait, and an openness trait. The key generating device generates a second key based on a document, where the second key indicates the writing style of the author of the document. A processor compares the first key to the second key to determine the degree of dissimilarity between the writing style of the user and the writing style of the author of the document.