Preregistration: Is the AI Crown Worth Anything? Prediction-Market Surprises in the AI Race and Big Tech Stock Prices

Preregistration (version 1.0 with two dated amendments, 1 November 2026) for the research paper "Is the AI Crown Worth Anything? Prediction-Market Surprises in the AI Race and Big Tech Stock Prices". The study uses Polymarket and Kalshi contracts on which company will have the best AI model (resolved on the LMArena text leaderboard) to measure surprises in the AI race, and tests whether changes in these odds while the stock market is closed predict the overnight abnormal returns of the companies involved (main test: Alphabet and Google's odds). The document fixes the research questions, data, measures, exclusions, hypotheses, multiple-testing correction, placebo checks and interpretation rules before any analysis of stock returns. At the time of publication no stock return had been computed from the real data; the main analysis will be run once, after the data freeze on 30 November 2026.