Wonyeol Lee (POSTECH)

Date: Monday, January 12 2026 – 13h00
Place: A008
Title: Random Variate Generation with Formal Guarantees

Standard software libraries for random variate generation are based on “Real-RAM” algorithms, which assume infinite precision. The “Real-RAM” assumption, however, is unrealistic as any software implementation must use only finite precision. As a result, existing libraries lack formal guarantees, leading to unknown output distributions, runtime errors, and inconsistent APIs. In this talk, I will present a new approach to principled and practical random variate generation with formal guarantees. The key idea is to first specify the desired probability distribution in terms of a finite-precision numerical program that defines its cumulative distribution function (CDF), and then generate exact random variates according to this CDF. We present a universal and fully automated method to synthesize exact random variate generators given any numerical CDF. The method attains the information-theoretically optimal entropy rate, consuming the least possible number of input random bits per output variate. We develop a random variate generation library using our method, and demonstrate that it has competitive runtime with GNU Scientific Library while delivering higher accuracy, entropy efficiency, and automation.