Author problems

I’m having problems with the author in the posts.

When I visit my blog it says “Author:” without author, but when I login, eg, with the User “Richard”, all the posts that were created by him, appears “Author: Richard” and the other posts without anything.
Then I change the User to “Jake”, and all posts made by him appear “Author: Jake” and other “Author:” nothing …

How do you always show the authors, regardless of being logged in or not!?