Aston Villa are better than Chelsea base on performance, they are ready to get 3pt more than the Chelsea side. I think the Villains have faced difficult opponents than Chelsea and they made a good account of themselves but Chelsea have more easy games than Aston Villa but they fail to get something out of it. If you ask me I'd rate Aston Villa ahead of Chelsea because I see the Aston Villa team as one that's consistent this season while Chelsea are finding it hard to be stable, they (the Blues) are like a switch, off and on.
Aston Villa and Chelsea have same 14 points, and they have small differences in goals and conceded goals. Their quality is nearly the same and one good or bad match does not change their quality, it's about recent form only.
They meet each other in a direct match and they equal chance to win it. A latest match result will be used as one of biggest things for a match prediction but with same quality, as said, they can beat the opponent even they are considered as weaker and had a latest worst performance and result. In a direct match, previous opponents you met are not too important, and the opponent in this match is important. Both Chelsea and Aston Villa are strong and ambitious, they will not lose this direct match easily because it's more important than a single match. It can decided their competition for a fourth position too.