From DC Common Lottery Board September 2015 minutes - https://ms-dc.s3.amazonaws.com/docs/clb-meeting-minutes-91415.pdf
Algorithm Analysis: My School DC tested the algorithm design that uses a single random lottery number for each applicant, regardless of the number of school selections. We wanted to confirm that design this summer with our own data, since we now have two years of the common lottery under our belt. Our contractor ran 5,000 lottery simulations using real DC data and compared match results using single random numbers (SRN) and multiple random numbers (MRN). Both SRN and MRN maintained the overall match rate of about 72%, but SRN matched about 400 more students (2% of applicants) to their #1 choice than MRN did. Based on the results of that analysis, the design with the SRN remains preferable and My School DC will not be recommending an algorithm change to the Common Lottery Board for the 2016 lottery. |