<!--
{
  "availability" : [
    "iOS: 16.0.0 -",
    "iPadOS: 16.0.0 -",
    "macCatalyst: 16.0.0 -",
    "macOS: 13.0.0 -",
    "tvOS: 16.0.0 -",
    "visionOS: 1.0.0 -",
    "watchOS: 11.0.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "CreateMLComponents",
  "identifier" : "/documentation/CreateMLComponents/BoostedTreeConfiguration/rowSubsample",
  "metadataVersion" : "0.1.0",
  "role" : "Instance Property",
  "symbol" : {
    "kind" : "Instance Property",
    "modules" : [
      "Create ML Components"
    ],
    "preciseIdentifier" : "s:18CreateMLComponents24BoostedTreeConfigurationV12rowSubsampleSdvp"
  },
  "title" : "rowSubsample"
}
-->

# rowSubsample

Subsample ratio of the training set in each iteration of tree construction.

```
var rowSubsample: Double
```

## Discussion

This is called the bagging trick and can usually help prevent overfitting. Setting this to a value of 0.5
results in the model randomly sampling half of the examples (rows) to grow each tree. Must be in the range
(0, 1).

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)