From our abstract:
The gender difference is not robust to multiple rounds of competition. The evidence supports the argument that exposing females to competition (e.g., Title IX) may eliminate performance differences.
Past research finds that males outperform females in competitive situations. Using data from multiple-round math tournaments, we verify this finding during the initial round of competition. The performance gap between males and females, however, disappears after the first round. In later rounds, only math ability (not gender) serves as a significant predictor of performance.
Link to the paper here.