Chicago White Sox vs. Houston Astros: 1st inning tied?

This market resolves Yes if the first inning of the Chicago White Sox vs. Houston Astros game ends tied. We are on No, meaning at least one team scores in the first inning. The No price is 43%, while our estimate is 65%.

The key driver is the probability of a scoreless first inning. In MLB, roughly 70% of innings are scoreless, but the first inning with starting pitchers facing top-of-the-order hitters runs lower. White Sox and Astros starters allow about 0.4-0.5 runs per first inning on average, and top lineups swing aggressively. The combined probability that neither team scores typically falls in the 30-40% range, which matches the 43% price, but our model accounts for specific pitching weaknesses and puts the tie at 35%.

For No to win, only one run is needed in the first inning, via a home run, an error, or a hit streak. That happens in the majority of MLB games.

The main risk is a dominant starter throwing a quick first inning and weak top-of-the-order bats. The idea is invalidated if both starters have low first-inning ERAs and high strikeout rates.