---
title: biases
framework: coreml
role: symbol
role_heading: Type Property
path: coreml/mlparameterkey/biases
---

# biases

The key you use to access the biases of a layer in a neural network model.

## Declaration

```swift
class var biases: MLParameterKey { get }
```

## Discussion

Discussion The value type for the biases key is an MLMultiArray. You must scope this key with the name of the specific neural network layer whose biases you’d like to access. See scoped(to:). note: You can only override the biases of a model’s updatable layers. Model developers mark these layers as updatable with the Core ML Tools.

## See Also

### Accessing neural network layer parameters

- [weights](coreml/mlparameterkey/weights.md)