just out of curiosity...

The badge stars indicate the following "point tiers":

1. One star (0 - 1000) 
2. Two stars (1001 - 7500)   
3. Three stars (7501 - 25000)  
4. Four stars (25001 - 50000)     
5. Five stars (50001 - 500000)   

The number of points is calculated by the following factors:

• Post Factor: The amount each post is worth.
• Reply Factor: The amount each reply is worth for the original post.
• Replier Factor: The amount each unique replier is worth for the original post. Additional replies to the same post from the same replier are not included in calculation.
• Verified Answer Factor: The amount a member receives for having a reply verified as the answer.
• Rating Factor: The amount each rating is worth for the rated post.
• Download Factor: The amount each download is worth for the original post.
• Downloader Factor: The amount each unique downloader is worth for the original post. Additional downloads of the same post from the same downloader are not included in calculation.
• Favorite Post Factor: The amount each post receives for being selected as a favorite.
• Favorite User (Friend) Factor: The amount each user receives for being selected as a favorite/friend.
• Rater Factor: The factor used to determine the value of each rating for the rater (points = Rating * Rater Factor).
• Wiki Comments: The amount of points a user receives for adding a comment to a wiki article.
• Wiki Edits: The amount of points a user receives for editing a page in the wiki.
• New Page: The amount of points a user receives for publishing a new page to the wiki.

Any activities that act upon a member's own posts are not credited with points. For example, a post does not receive points for a reply if the author replies to himself/herself; rates his/her own post; downloads his/her own file, or marks his/her post as a favorite. 

Although the factors involved might be subjective to some, the points and rankings do provide some insight as to how each Be Communities member's overall contributions and "reputation" compare to others on the site.

Unknown said:

shouldn't you have some stars?

Not sure what you mean... like this?

If you are referring to this:

Those stars are different -- they are associated with the rating of the individual piece of content (i.e. forum post/reply, blog article, wiki article, file/image, etc.) That is one of a number of factors that then gets factored into each members "badge score", but is not the only thing that contributes to the level you have achieved.