Plexis (πλεξις)

Urban Knowledge Graph — How 200K entities and 1.49M edges weave Singapore's urban fabric
Subzone
326
URA Planning
Hex-8 1,191
637 features
Hex-8 1,191
Cafe
6.6K
Restaurant
20.9K
Retail
27.1K
Health
8.0K
174,711 places · 114 features
MRT
231
Bus
5,172
Hawker
129
HDB
10.4K
Anchors & infrastructure nodes
COMPETES (503K)
SYNERGIZES (263K)
ANCHORED_BY
CONNECTS_TO · OD_FLOW
GRADIENT
DEMAND
Commercial (941K edges)
Anchor (121K)
Transit (5.8K)
Demand flow
Gradient
Hierarchy (364K)
How each layer contributes
Commercial
941,834 edges
Place-to-place relationships. How businesses interact — compete, synergize, substitute, and co-locate.
COMPETES_WITH (503K) · SYNERGIZES_WITH (263K) · SUBSTITUTES_FOR (150K) · EXIT_FRONTAGE (3K) · VOID_DECK_OF (22K)
Embedding captures: competitors R²=0.77, category separability 310x
Hierarchy
364,058 edges
Containment and classification. Every place knows its hex, its subzone, and its category. Queries traverse up and down.
LOCATED_IN (175K) · IS_A (175K) · PARENT_OF (7.3K) · PART_OF (7.3K)
Enables: cross-level queries, category classification 69.8% accuracy
Anchor
121,053 edges
Places connected to demand generators — MRT exits, hawker centres, malls, schools. The "why is this cafe here?" layer.
ANCHORED_BY (108K) · WALK_CATCHMENT (6.6K) · SERVES (6.8K)
Embedding captures: anchor_score R²=0.91 — near-perfect
Transit
5,770 edges
Rail topology, bus feeders, commute flows, expressway corridors. How people MOVE — the skeleton the commercial flesh hangs on.
CONNECTS_TO (2.3K) · FEEDS_INTO (1.3K) · SAME_CORRIDOR (1.9K) · EXPRESSWAY (1.5K)
Embedding captures: transit_taps R²=0.65, transit_score R²=0.66
Spatial
27,551 edges
Adjacency with direction (N/S/E/W), road connectivity, barriers (expressways/canals), and coastline. The physical fabric.
ADJACENT_TO (24K) · N/S/E/W_OF (3.3K) · ROAD_CONNECTED (1K) · COASTAL (83)
Embedding captures: walkability R²=0.90, ecosystem R²=0.83
Gradient
9,263 edges
How things CHANGE across space — price contours, density waves, height skylines, commercial intensity. The urban texture.
COMMERCIAL_GRADIENT (4.2K) · HEIGHT (2.5K) · DENSITY (2.1K) · PRICE (437)
Enables: development front detection, gentrification boundaries
Supply-Demand
5,260 edges
Where demand exists but supply doesn't. Gap edges, oversupply flags, demand leak paths, comparable neighborhoods.
UNDERSUPPLIED (1.3K) · OVERSUPPLIED (637) · COMPARABLE_TO (2.7K) · DEMAND_LEAKS_TO (116) · WORKER_INFLOW (589)
Embedding captures: demand_context R²=0.88, pull_residential R²=0.89
Structure
10,758 edges
Cluster membership, land-use transitions, development fronts. The macro-patterns that shape Singapore's urban evolution.
SAME_CLUSTER (5.3K) · DEVELOPMENT_FRONT (3K) · LU_TRANSITION (904) · SYNERGY_PAIR · SUBSTITUTES
Embedding captures: archetype NMI=0.36, population R²=0.78
The two-head embedding
Spatial Head (64d)
Encodes WHERE — walkability, population, ecosystem, transit reach. Trained on hierarchy + spatial + transit edges.
walkability R²=0.90
ecosystem R²=0.83
population R²=0.78
Commercial Head (64d)
Encodes WHAT — category, competition, demand match, synergy. Trained on commercial + supply-demand edges.
category accuracy 69.8%
separability 310x
anchor R²=0.91
Full Embedding (128d)
Concatenation of both heads. Used for similarity search, brand expansion, anomaly detection, and scenario simulation.
demand_context R²=0.88
competitors R²=0.77
survivability R²=0.48
Live example — Toa Payoh Central
One hex-8 cell: 32,678 residents · 1,460 places · 14,176 graph edges · Dense HDB archetype
Toa Payoh Central
32,678 pop · 111 HDB
2 MRT · 20 bus stops
h9-1
h9-2
h9-3
h9-4
h9-5
Durian Era
Cafe
Kakak Cafe
Cafe
Saizeriya
Restaurant
Old Chang Kee
Restaurant
Ai Mui Optical
Health
SG Hokkien
Education
Toa Payoh Mall
Retail
Ping Xiang
Hawker
Toa Payoh
MRT
Braddell
MRT
Bus 52139
Hawker
Centre
School
HDB Blks
111 blocks
Void deck
737 places
Balestier
Boon Teck
Braddell
TP West
GRADIENT↑
price/height
COMPETES 5,179
SYNERGIZES 2,138
ANCHORED 1,231
VOID_DECK 737
ADJACENT 36 edges to 6 neighbors
PARENT_OF ↓ 7 children
14,176
Total edges
from this one hex
5,179
Competition
same-category within 500m
2,138
Synergy
cross-category co-benefit
737
Void deck
places in HDB blocks

What this graph tells us about Toa Payoh Central

5,179 competition edges mean 1,460 places compete intensely within 500m — this is a saturated commercial centre (ecosystem 0.86). Saizeriya has 85 restaurant competitors. Toa Payoh Mall has 57 retail competitors.

2,138 synergy edges show cafes benefiting from offices, health clinics clustering together, hawkers drawing foot traffic that spills to retail. The food ecosystem (hawker + cafe + restaurant) synergizes with the education cluster (tuition centres).

737 void deck edges — half the places are in HDB void decks with captive demand from the 111 blocks above. This is the SGP-specific pattern: barbers, TCM clinics, provision shops serving residents who literally walk downstairs.

1,231 anchor edges connect places to 2 MRT stations (Toa Payoh + Braddell), 20 bus stops, and the hawker centre. The transit funnel through Toa Payoh MRT drives 183K daily taps — the primary demand generator.

36 adjacency edges to 6 neighbors (Balestier, Boon Teck, Braddell, TP West). Price/height gradients show Toa Payoh is a local peak — commercial intensity drops in every direction.

Plexis · SGP Digital Atlas · 200K nodes · 1.49M edges · 39 relations · 8 families · 128d R-GCN