I think it’s a little different comparison for overall schools versus track. For men’s track right now Cornell is the best of those three, with Dartmouth in the middle and Yale the least strong. In terms of points at the Heps, the gap between Cornell and Dartmouth/Yale is large and the gap between Dartmouth and Yale is relatively modest.
When you look at cross-admit data (for all admits, not just athletes) though around 90% choose Yale over Cornell or Dartmouth. The link below is one data source on this and Parchment shows similar data. That’s not saying Yale is best for everyone, just that most people tend to choose Yale of that set of schools.
http://www.nytimes.com/imagepages/2006/09/17/weekinreview/20060917_LEONHARDT_CHART.html