A .NET implementation of the Rapid Automatic Keyword Extraction algorithm as described in Rose, S., Engel, D., Cramer, N., & Cowley, W. (2010). Automatic Keyword Extraction from Individual Documents. In M. W. Berry & J. Kogan (Eds.), Text Mining: Theory and Applications: John Wiley & Sons.
Implementation is also based on the python version at https://github.com/aneesha/RAKE.