In my LinkedIn profile, my name was listed as Richard (Rick) Upton, which was useful when LinkedIn didn't know that Rick is a nickname for Richard: Users could search for either Rick Upton or Richard Upton and find me either way.
LinkedIn has since implemented an enhancement to enable its search engine to know that Rick is a nickname of Richard. More recently, LinkedIn has begun publishing a publicly accessible directory of LinkedIn users for those users who have agreed to having their profile shown on the Internet. Here are two examples:
When my profile name was Richard (Rick) Upton, my name didn't show up on either of the lists above. Now that I have changed my profile name to Richard Upton, I show up on both lists.
Maybe you are in a situation similar to the one that I was in?
UPDATE April 27, 2015: My profile name on LinkedIn is now Rick Upton.