Base rate for VOO 1d up is ~54%. Evidence updates me downward: VOO rallied ~+2.5% over the prior two sessions into quarter-end (670→686.8), and the July 1 Polymarket contract implies only ~27% probability the index opens higher, with heavy event risk (ADP jobs, ISM manufacturing, Fed Chair Warsh). Mean-reversion after a stretched two-day pop plus a bearish premarket tilt me to down at modest confidence.