> ## Documentation Index
> Fetch the complete documentation index at: https://docs.learningcommons.org/llms.txt
> Use this file to discover all available pages before exploring further.
# Standards crosswalks
> Reference for standards crosswalk relationships in Knowledge Graph: map state mathematics standards to Common Core using Jaccard similarity and learning component overlap.
## Overview
The Standards crosswalk relationship connects state mathematics standards to their closest matching Common Core State Standards (CCSSM) based on measurable overlap of Learning Components (LCs).
Crosswalks provide developers and content providers with a scalable way to extend mappings from CCSSM to state-specific frameworks without having to independently replicate matching logic. By leveraging the LC superset, crosswalks show where state and CCSSM standards converge in content coverage. This data can be used to more easily adapt content aligned to CCSSM for use in specific jurisdictions
Key characteristics:
* Evidence-based mapping: Crosswalks are built only when standards share at least one LC.
* Similarity measurement: Each relationship includes a jaccard similarity score and supporting counts of LCs.
* Directionality: Crosswalks always connect from a state standard → CCSSM standard and not between states.
* Scope: Limited to math standards in states where [LC alignment](/knowledge-graph/entity-and-relationship-reference/learning-components) exists.
This design ensures that crosswalks are transparent, consistent, and extensible as additional states’ LC alignments are completed.
## Data relationship diagram
The diagram shows **crosswalks** only: state mathematics standards mapped to Common Core State Standards. Both endpoints are `StandardsFrameworkItem` (defined in [Academic standards](/knowledge-graph/entity-and-relationship-reference/academic-standards)). Direction is always state → CCSS, not between states. Edge properties include jaccard and LC counts; see the Relationship properties section below.
**Example (New York → CCSS):** A **state standard** is a `StandardsFrameworkItem` from a state framework—e.g. *NY 3.NF.1 (Understand a fraction 1/b as the quantity formed by 1 part when a whole is partitioned into b equal parts)*. A **CCSS standard** is a `StandardsFrameworkItem` from Common Core Math—e.g. *3.NF.A.1*. A **hasStandardAlignment** edge connects them when they share at least one Learning Component; the edge has properties such as `jaccard` (e.g. 0.85), `stateLCCount`, `ccssLCCount`, `sharedLCCount`. So: NY 3.NF.1 -\[:hasStandardAlignment]-> 3.NF.A.1. Crosswalks are only state → CCSS (never state → state).
**Edge list (source → relationship → target):**
* `StandardsFrameworkItem` (state) → `hasStandardAlignment` → `StandardsFrameworkItem` (CCSS) (e.g. NY 3.NF.1 → 3.NF.A.1)
## How Crosswalks Are Generated
### Relationship properties
Each crosswalk is represented as a directional relationship:
`(state standard) -[:hasStandardAlignment]-> (ccss standard)`
The relationship includes quantitative measures of similarity:
| **Property** | **Description** |
| :------------ | :---------------------------------------------------------------------------- |
| jaccard | Proportion of shared LCs between state and CCSS standards (0 \< jaccard ≤ 1). |
| stateLCCount | Number of Learning Components supporting the state standard. |
| ccssLCCount | Number of Learning Components supporting the CCSS standard. |
| sharedLCCount | Number of Learning Components shared by both standards. |
Only standards with at least one shared LC are included. Every `hasStandardAlignment` edge represents an evidence-based connection.
### Understanding the Jaccard index
The Jaccard index measures similarity between two sets — here, the sets of Learning Components that support each standard.
*Jaccard = Shared LCs ÷ (State LCs + CCSS LCs − Shared LCs)*
* A score of 1.0 means the standards share *all* of their Learning Components.
* A score of 0.0 means they share *none*.
* Scores between 0 and 1 indicate *partial overlap*, with higher values representing stronger similarity. Depending on your use case, you may be interested in overlaps above a threshold between 0 and 1.
Example: If a state standard has 5 Learning Components and a CCSSM standard has 6, and they share 4 of them: *Jaccard*=4/(5+6−4)=0.57. This means about 57% of their underlying skills overlap.
## Crosswalk relationship
### hasStandardAlignment
A `hasStandardAlignment` connects a State Standard `StandardsFrameworkItem` to a CCSS Standard `StandardsFrameworkItem` when the two share overlapping Learning Components.
`(:StandardsFrameworkItem) -[:hasStandardAlignment]-> (:StandardsFrameworkItem)`
#### Example
```json JSON theme={null}
{
"type": "relationship",
"identifier": "3edc451c-392b-50ad-addd-d6b76ab7ab49",
"label": "hasStandardAlignment",
"properties": {
"dateCreated": "2026-01-02",
"license": "https://creativecommons.org/licenses/by/4.0/",
"targetEntity": "StandardsFrameworkItem",
"attributionStatement": "Knowledge Graph is provided by Learning Commons under the CC BY-4.0 license.",
"description": "A hasStandardAlignment relationship connects a State standard to a CCSS standard when the two are supported by overlapping sets of Learning Components. The relationship indicates an evidence-based crosswalk derived from measurable overlap of deconstructed skills, expressed through properties such as jaccard and LC counts. It does not imply sequence, dependency, or pedagogical progression, only the degree of shared content between the two standards.",
"dateModified": "2026-01-02",
"identifier": "3edc451c-392b-50ad-addd-d6b76ab7ab49",
"stateLCCount": "2",
"provider": "Learning Commons",
"sourceEntity": "StandardsFrameworkItem",
"sharedLCCount": "2",
"sourceEntityKey": "caseIdentifierUUID",
"ccssLCCount": "2",
"author": "Learning Commons",
"jaccard": "1.0",
"targetEntityKey": "caseIdentifierUUID",
"relationshipType": "hasStandardAlignment"
},
"source_identifier": "20d6435a-4b7f-53b7-abcc-cb61dcd36679",
"source_labels": ["StandardsFrameworkItem"],
"target_identifier": "74721dc3-d49c-5f16-804c-4cb07fca6ed6",
"target_labels": ["StandardsFrameworkItem"]
}
```