<div class="section-label"><span class="num">05</span> Relevance Metrics</div>
<div class="section-title">Score <em>relevance</em> without predicting.</div>
Sometimes you want the building blocks on their own: how similar each past case is to your circumstances, how informative those cases are, and how they combine into relevance, without forming a full forecast.
These scores are what Predict, MaxFit, and Grid use internally when they decide which observations enter the weighted average. For a full forecast, prefer [[Grid Prediction]].
## Signature
```text
relevance(X, theta, cov_inv?) → scores, length N
similarity(X, theta, cov_inv?) → scores, length N
info_x(X, cov_inv?) → scores, length N # no theta
info_theta(X, theta, cov_inv?) → score, length 1
relevance_metrics(X, theta, cov_inv?) →
optional: relevance, similarity, info_x, info_theta
```
**Calls:** `relevance`, `similarity`, `info_x`, `info_theta`, `relevance_metrics`
**Returns:** score vectors (or a bundle of the scores you request)
## Arguments
| Name | Shape | Description |
| --- | --- | --- |
| <span class="mono">X</span> | N × K | Training attributes |
| <span class="mono">theta</span> | K | Circumstances (not used by <span class="mono">info_x</span>) |
| <span class="mono">cov_inv</span> | K × K | Optional inverse covariance; if omitted, the engine estimates it from <span class="mono">X</span> |
N = number of observations (rows), K = number of independent variables (columns).
With <span class="mono">relevance_metrics</span>, request only the scores you need.
## Results
Each call returns score vectors you can inspect on their own. The same quantities can also appear on a prediction result under [[Results/Weights & Insights|Weights & Insights]].
| You get | Shape | Look here |
| --- | --- | --- |
| Similarity | N | How close each training row is to <span class="mono">theta</span> |
| Informativeness of X (<span class="mono">info_x</span>) | N | How unusual each row is vs the sample mean |
| Informativeness of θ (<span class="mono">info_theta</span>) | 1 | How unusual <span class="mono">theta</span> is vs the sample mean |
| Relevance | N | Combines similarity with informativeness of the row and of <span class="mono">theta</span> |
When you run Predict, MaxFit, or Grid, censoring chooses **relevance** or **similarity** (or both on MaxFit and Grid) as the score that decides include vs exclude.
## Related
- [[Functions/Overview|Functions]]
- [[Predict]] · [[Grid Prediction]]
- [[Settings/Options#PredictOptions|PredictOptions]] · [[Results/Weights & Insights|Weights & Insights]]