> ## Documentation Index
> Fetch the complete documentation index at: https://kumo.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# aggregation

#### `aggregation: <list[list[sum | mean | max | min | std | var]]>` (Optional)

## Description

A nested list of aggregation operators in graph neural network aggregation process.

### Supported Task Types

* All

### Example

<CodeGroup>
  ```yaml theme={null}
  aggregation: [[sum, mean, max, var]]
  aggregation: [[sum, mean, max, min, std], [sum, max]]
  ```
</CodeGroup>

### Default Values

| [run\_mode](/run-mode) | Default Value                                    |
| ---------------------- | ------------------------------------------------ |
| FAST                   | `[[sum, mean, max], [sum, mean, min, max, std]]` |
| NORMAL                 | `[[sum, mean, max], [sum, mean, min, max, std]]` |
| BEST                   | `[[sum, mean, max], [sum, mean, min, max, std]]` |