As with both the Facebook and Google Plus Connect features of the Social Review Engine, in order to use LinkedIN Connect for Review Submissions you must create a LinkedIN APP.  


Here is where you will insert your LinkedIN APP Information in the General Settings:

LinkedIn App Settings


*This step is required in order to use LinkedIN Connect for Review Submissions.


Go to the Creating A LinkedIn App Knowledge Base page to see a complete step by step tutorial on how to create an Application for LinkedIn.