I think there is a pattern somewhere waiting to be discovered.
Data: LinkedIn, Angel.co and crunchbase
Analyze: 1. Analyze the Profile of the person who joins *small* company. (define: small - could be filtered)
2. If a% joins (were some% of his connections working there earlier? etc. related questions)
3. Education brackets, years of experience before taking the *plunge*
*I am not sure of the what all data can be accessed from the API of listed data providers.