HITS

SQL function: cugraph_hits

Official cuGraph reference: C API

Compute mutually reinforcing hub and authority scores: strong hubs point to strong authorities, and strong authorities are linked from strong hubs.

Quickstart

The call below supplies edges from registered relation target_edges with canonical src and dst columns and may include weight. Substitute your own registered relations.

SELECT * FROM cugraph_hits(edges => (SELECT src, dst FROM target_edges));

Inputs

Every relation is a named parenthesized SELECT subquery. The required edges role uses canonical src and dst columns; every role, its canonical columns, and their accepted Arrow types are listed under Relation arguments. Metadata validation resolves registered tables named in its JSON request.

Endpoint columns accept numeric Int32, Int64 vertex IDs or logical string Utf8, LargeUtf8, Utf8View vertex IDs; string vertex-identity outputs are canonicalized to Utf8 (native mapping Int64) while scores, distances, counts, coordinates, and opaque labels stay numeric. The shared vertex-ID contract is summarized in Vertex ID support; the concrete call-specific schema comes from gpu_validate_call.

Logical string side-input limitations:

• edge ID columns and edge-ID predicate side inputs are not supported for logical string graphs

Arguments and options

Relation arguments

Argument	Required	Columns	Description
edges	yes	src, dst: Int32, Int64, Utf8, LargeUtf8, Utf8View weight (optional): Float32, Float64 edge_id (optional): Int32, Int64	edge relation with canonical src and dst columns, plus optional weight and edge_id columns

Every edge_id column must have the integer type of src and dst; string-keyed graphs accept no edge IDs.

Named value arguments

Option	Type	Default	Constraints	Description
epsilon	number	0.00001	> 0	positive convergence tolerance
max_iterations	integer	100	min 1; max 4294967295	maximum iteration count, at least 1
normalize	boolean	false		whether HITS scores are normalized

Graph construction options

Graph construction follows the shared defaults (directed=true, renumbering, python_cugraph policy) documented in Graph Construction Options.

Output

Column	Type	Nullable	Description
vertex	Int64|Utf8	no	Vertex receiving HITS scores.
hub_score	Float64	no	HITS hub score for the vertex.
authority_score	Float64	no	HITS authority score for the vertex.

These are generic descriptor schemas; run gpu_validate_call to get the concrete, table-specific output schema.

Examples

This example runs on the citation network demo dataset.

Hubs versus authorities

HITS returns two scores per vertex in one pass. In a citation graph they separate two kinds of importance that PageRank blends: a hub cites many authorities (typically a survey), and an authority is cited by many hubs (typically a foundational result). One call feeds two ORDER BY clauses:

SELECT p.year, p.n_references, p.title
FROM cugraph_hits(edges => (SELECT src, dst FROM citation_edges)) h
JOIN papers p ON p.paper_id = h.vertex
ORDER BY h.hub_score DESC
LIMIT 4;

year	n_references	title
2019	292	Deep Learning for Generic Object Detection: A Survey
2018	276	Deep Learning for Generic Object Detection: A Survey.
2015	299	Recent Advances in Convolutional Neural Networks
2019	211	Object Detection With Deep Learning: A Review

SELECT p.year, p.n_citation, p.title
FROM cugraph_hits(edges => (SELECT src, dst FROM citation_edges)) h
JOIN papers p ON p.paper_id = h.vertex
ORDER BY h.authority_score DESC
LIMIT 4;

year	n_citation	title
2004	35,541	Distinctive Image Features from Scale-Invariant Keypoints
2014	18,029	VERY DEEP CONVOLUTIONAL NETWORKS FOR LARGE-SCALE IMAGE RECOGNITION
2012	16,802	ImageNet Classification with Deep Convolutional Neural Networks
2005	19,433	Histograms of oriented gradients for human detection

The top hubs are titled "Survey" and "Review"; the top authorities are SIFT, VGG, AlexNet, and HOG. The mutually reinforcing definition places both lists in the field with the densest hub/authority structure (computer vision) without any field labels supplied as input.

Limits

No algorithm-specific limitations.

To dry-run validate relation metadata, column types, and options without execution, see gpu_validate_call.