Understanding the statistics behind NRFI and YRFI picks helps you evaluate each matchup. Here is what each metric means and why it matters for first-inning betting.

FIP (Fielding Independent Pitching)

A pitching metric that isolates outcomes a pitcher directly controls: strikeouts, walks, hit-by-pitches, and home runs. Unlike ERA, FIP removes the influence of fielding and luck on batted balls. FIP is the single strongest predictor of first-inning scoring (r=0.31 year-to-year). A lower FIP indicates a more effective pitcher, making NRFI more likely.

K% (Strikeout Rate)

The percentage of plate appearances that end in a strikeout. Pitchers with higher K% generate more outs without the ball being put in play, reducing the chance of a first-inning run. League average is around 23.4% for qualified starters.

Barrel%

The percentage of batted balls classified as "barrels", batted at optimal exit velocity (95+ mph) and launch angle (26-30 degrees) for extra-base hits. Lower barrel rate means the pitcher prevents the most damaging type of contact. League average is approximately 10.2%.

xwOBA (Expected Weighted On-Base Average)

A Statcast metric that measures the quality of contact a pitcher allows, based on exit velocity and launch angle. Unlike batting average, xwOBA accounts for how hard the ball was hit regardless of the outcome. Lower xwOBA means the pitcher limits hard contact. League average is around .310.

1st Inning ERA

A pitcher's earned run average in the first inning specifically. While useful for context, 1st inning ERA has very low year-to-year correlation (r²=0.003), meaning it is mostly noise in small samples. Our model uses it as a minor signal alongside more predictive metrics like FIP and K%.

NRFI Rate

The percentage of a pitcher's starts where no runs scored in the first inning. Calculated from linescore data across multiple seasons. A higher NRFI rate suggests the pitcher consistently keeps the first inning clean. Displayed alongside the number of game starts (GS) for sample size context.

MIX/RISK (Pitch Mix & Top-Order Risk)

A combined indicator showing a pitcher's arsenal depth (number of distinct pitch types thrown regularly) and the opposing lineup's top-of-order threat level. More pitch types make a pitcher harder to predict in early at-bats. Higher top-order risk means the first three batters pose a greater scoring threat.

Park Factor

A multiplier that measures how a ballpark affects run scoring compared to the league average. A park factor above 1.00 (e.g., Coors Field at ~1.35) means more runs are expected. Below 1.00 favors pitchers. Our model applies park factor as a multiplicative adjustment to the base NRFI probability.

Model %

Our model's estimated probability that no runs will score in the first inning. Calculated using a research-backed weighted formula that combines pitcher FIP, strikeout rate, barrel rate, xwOBA, pitch mix, recent form, NRFI rate history, and top-order lineup risk, with a park factor adjustment.

Market %

The implied NRFI probability derived from consensus sportsbook odds. Calculated by converting American odds to implied probability. Comparing our model's probability to the market price reveals whether a bet offers positive expected value.

Edge

The difference between our model's NRFI probability and the market-implied probability. A positive edge (e.g., +3.2%) means our model sees NRFI as more likely than the market suggests, indicating potential value on an NRFI bet. A negative edge suggests YRFI value.

Confidence Score

A 0-100 rating reflecting how reliable our model's prediction is for a given game. Factors in data completeness (50% weight, are all stats available?), edge magnitude (30%, is the edge large enough to overcome vig?), and sample size (20%, how many starts does each pitcher have?). Higher scores indicate more conviction.