How to read simulation ranges
A distribution is more honest than a single score, but only if its ranges and probabilities are interpreted correctly.
Reviewed
Median versus most frequent result
The median is the point with half the simulated values below it and half above it. The mode is the single most frequent value. They can differ, especially in skewed or discrete distributions. Calling either one “the prediction” discards the uncertainty that simulation was designed to show.
What a central 80% range means
A central 80% interval usually runs from the 10th percentile to the 90th percentile. Under the model, about one result in ten falls below it and one in ten above it. It is not an 80% guarantee about reality; it is a summary of modeled outcomes conditional on the inputs.
Wide and narrow ranges
A wider range indicates more dispersion in the simulated variable. That can come from the sport, the market, a volatile role, or weaker constraints in available prices. A narrow range does not necessarily mean the estimate is more accurate: a model can be confidently wrong if its inputs or assumptions are wrong.
Comparing a line with a distribution
When a sportsbook threshold is placed against a simulated distribution, the relevant question is how much probability lies on each side, not merely whether the median is above or below the line. A median of 20.5 against a line of 20 can coexist with only a small probability difference once rounding, pushes, and a wide distribution are considered.
A careful reading checklist
- Confirm the odds and simulation timestamps.
- Identify whether the summary is a median, mean, mode, or percentile.
- Read the interval label and its stated coverage.
- Check settlement rules and whether the statistic is discrete.
- Keep model sampling error separate from real-world uncertainty.
- Do not infer a recommendation from descriptive probability alone.
See Monte Carlo sports simulation for how these distributions are produced.