---
title: "EvidenceRef"
description: "one piece of evidence: a unit of any kind, with its basis and its weight"
section: concepts
address: /concepts/evidenceref
contract: 0476e35e6e275db5
---

# EvidenceRef

one piece of evidence: a unit of any kind, with its basis and its weight

[figure: EvidenceRef is a value at none scope. The drawing shows its fields and the objects that they point at.]

| property | value |
|---|---|
| kind | value |
| scope | none |
| key | none |
| store | none |
| family | kernel |



## Fields


| field | type | required | note |
|---|---|---|---|
| `unit` | `id` | yes | a fact, an observation, a preview or a reading |
| `basis` | [Basis](/concepts/basis) | yes | measured or inferred |
| `weight` | `share` | no |  |
| `note` | `text` | no |  |
| `partition` | `id` | no | the catalogue entry of the partition that holds the unit, written at accept; required when the unit is a fact of the lakehouse |



## Routes that use it
No route takes or returns EvidenceRef directly. The record holds it, and the objects that point at it reach it.