I'm providing the user with the option to rate news articles 1-5 stars. I'm trying to determine the quality and interest of articles based on the user ratings. My first thought was:

• Interest = total number of ratings
• Quality = average rating

I.e. a user rates articles that it is interested in and gives higher rating for quality articles. The problem is that users may give an article a positive rating as a sign of interest or a negative as a sign of disinterest - regardless of the quality of the article. So positive/negative ratings may indicate interest and/or quality, or it may not depending on the user's intention. The metrics overlap and it gets confusing.

One solution to this is to provide the user with two ways to rate the content:

"Does the subject of this article interest you?" (YES/NO)
"What do you think of the quality of this article?" 1-5 stars

It makes things more clear in terms of how I can use the data, but the user may be confused by it. Do you think this is a good idea or not? Is there a better way to determine quality and interest of content?