Skip to main content
The Metrics page is where you turn raw events or warehouse facts into measurable numbers — and where you read experiment results.
Metrics list placeholder

The list

Each metric:
  • Name — human-readable
  • Source — a Traffical-native event or a warehouse fact
  • Aggregationconversion_rate, sum, count
  • Used by — policies attached as goal or health metrics
  • Current value — the latest computed aggregate across all traffic
The same metric can be used in many policies. Defining revenue_per_user once and attaching it to every checkout-related experiment is the common pattern.

Creating a metric

Metric editor placeholder
Pick a source first:
SourceWhat it means
EventAggregate a Traffical-native track event
FactAggregate a warehouse-native fact definition
Then pick an aggregation:
AggregationNumeratorDenominatorOutput
conversion_rateUnique users with ≥ 1 eventUnique users exposedProportion (0–1)
sumSum of value columnUnique users exposedPer-user average
countCount of eventsUnique users exposedPer-user rate
For sum, you also pick the value column (e.g. order_total). For count, no column is needed.
Metric definitions can also live as config-as-code in .traffical/metrics.yaml and be pushed via the CLI — see the config file and CLI reference. Attaching a metric as a policy’s goal or guardrail is done in the dashboard (below).

Filters and dimensions

A metric can be filtered (e.g. “only completed orders”) or grouped by a dimension (e.g. by country). For event-sourced metrics, the available filters and dimensions come from properties marked dimension: true on the event’s property schema. For fact-sourced metrics, available filters are columns returned by the fact SQL.

Metric detail

Metric detail placeholder
The detail page shows:
  • Current value with trend over time
  • Top breakdowns by configured dimensions
  • All policies using this metric as a goal or health gate
Use the time-range selector to look at any window.

Attaching to policies

Open a policy → MetricsAdd metric.
Attach metric placeholder
A policy can have:
  • One goal metric. What the experiment is optimizing for (drives adaptive allocation shifts, surfaces as the primary result).
  • Any number of guardrail metrics. Side effects you want to watch.
  • Rollout health metrics. For policies with a rollout, metrics that gate ramp progression.
For adaptive policies, only the goal metric drives the engine. Guardrails are surfaced in the UI but don’t influence allocations.

Reading per-policy results

On a policy’s detail page, each metric shows per-allocation:
  • The point estimate (e.g. conversion rate = 0.087)
  • A confidence interval
  • A significance indicator (when the experiment has enough data to make a confident call)
Policy metric results placeholder
Significance is computed using cluster-robust standard errors when the metric is measured at a different level than the randomization (e.g. randomized by company, measured per user). The dashboard handles this automatically based on entity definitions.

Best practices

  • Pick metrics carefully. A metric that’s noisy at your traffic level will say “no significant effect” forever. Use a more direct outcome where possible.
  • Don’t add too many guardrails. Three is plenty. Twenty is paralyzing.
  • Match metric to randomization level. If your project is keyed on companyId, prefer company-level metrics for goals. User-level metrics are still valid with cluster-robust analysis but slow to converge.

Next steps

Experiment design

Picking goal metrics and guardrails.

Definitions

Where warehouse-native fact definitions live.

Rollouts

Health-gated progressive delivery.