Critics do not agree on what the cutoff is for a recommendation, even when they use the same scale. Gene Siskel and Roger Ebert "both considera three-star rating to be the cutoff for a "thumbs up" on their scales of zero to four stars. Film critic Dave Kehr – who also uses a 0–4 star scale – believes "two stars is a borderline recommendation". On a five-star scale, regardless of the bottom rating, 3 stars is often the lowest positive rating, though judging on a purely mathematical basis, 2 1/2 stars would be the dividing line between good and bad on a 0-5 scale. Common Sense Media uses a scale of one to five, where 3 stars are "Just fine; solid" and anything lower is "Disappointing" at best.