JGAAP (Java Graphical Authorship Attribution Program) is a modular application for text categorization, textual analysis, and also authorship attribution. It is build in Java so there should be no problems in running it across a variety of platforms.
JGAAP uses a set of five tabs to do authorship analysis:
1. Construct a data set including training and testing documents
2. "Canonicize" the documents to eliminate extraneous variation
3. Convert the documents into "event sets" such as words, characters, parts of speech, or whatever
4. Apply an appropriate statistical analysis method
5. Read the results from the final screen

To run JGAAP in Windows, click on the jgaap.jar file in the bin directory. On Unix-based systems, or from the Windows command-line, you can also run:
java -jar jgaap.jar
from the bin directory.

JGAAP also has a command line mode. You can see the command line options by running:
java -jar jgaap.jar help
from the bin directory.

Requirements:
* Java

The license of this software is Freeware, you can free download and free use this calculator software.