NUMBERS IN PERSPECTIVE: Last week we took a dip into the enrollment and pass numbers in light of numbers released for edX's 6.002x circuits course. Astute readers were quick to point out the folly of calculating pass rates based on the number of signups--since free things typically don't elicit commitment. edX's Director of Content Development, Howard Lurie, suggested a better framework: comparing completion rates based on the number of students who actually attempted the first problem set. (Turns out 55% had already dropped out by this point). Seen in this light, the pass percentages for the edX course (27%, or 7,157 / 26,349) and Stanford/Coursera's database course (26%, or 6,500 / 25,000) are pretty close. Jose Padrica, a connoisseur who's sampled nearly all the offerings, firmly stated that 6.002x "had, by far, the heaviest workload...[with] real design problems, compared to just concept questions," though he attributed that to a much higher prerequisites.