# Enum: AggregationType 




_How to aggregate time series data_



<div data-search-exclude markdown="1">

URI: [tvbo:enum/AggregationType](https://w3id.org/tvbo/enum/AggregationType)

## Permissible Values
| Value | Meaning | Description |
| --- | --- | --- |
| mean | None | Average over time |
| median | None | Median over time (per node) |
| variance | None | Variance over time (per node) |
| std | None | Standard deviation over time (per node) |
| first_passage | None | First-passage time index (per node): the first sample at which the source cro... |
| last | None | Last value in window |
| first | None | First value in window |
| window | None | Sliding window aggregation |
| none | None | No aggregation |




## Slots

| Name | Description |
| ---  | --- |
| [aggregation](../slots/aggregation.qmd) | How to aggregate over time |










## Identifier and Mapping Information





### Schema Source


* from schema: https://w3id.org/tvbo






## LinkML Source

<details>
```yaml
name: AggregationType
description: How to aggregate time series data
from_schema: https://w3id.org/tvbo
rank: 1000
permissible_values:
  mean:
    text: mean
    description: Average over time
  median:
    text: median
    description: 'Median over time (per node). Robust to phase-slip / outlier samples
      that bias the mean. For an Observation.dynamics observer this is computed streaming:
      a per-node histogram (bins from the observation''s `histogram` slot) is folded
      into the integrator carry and the 0.5 quantile is read at finalize, so no trajectory
      is held.'
  variance:
    text: variance
    description: Variance over time (per node)
  std:
    text: std
    description: Standard deviation over time (per node)
  first_passage:
    text: first_passage
    description: 'First-passage time index (per node): the first sample at which the
      source crosses the observation''s `threshold` parameter (>=), or the sample
      count if it never crosses. Backend-independent (argmax of the threshold-crossing).
      Multiply by the sampling step for a time.'
  last:
    text: last
    description: Last value in window
  first:
    text: first
    description: First value in window
  window:
    text: window
    description: Sliding window aggregation
  none:
    text: none
    description: No aggregation

```
</details>

</div>