State-of-the-art temporal-link-prediction (TLP) models are, in essence, multi-channel information aggregators: they combine an interaction-history channel, a time-encoding channel, and a structure channel. The first two have been refined relentlessly; the structure channel remains a crude afterthought -- DyGFormer encodes it as a 1--2-bit neighbour-cooccurrence count. We begin with a measurement: on sparse temporal graphs the classical 1-hop common-neighbour signal is near-random (discriminative AUC ≈0.50), because two nodes almost never share a direct neighbour; the genuinely discriminative signal lies one hop deeper -- the 2-hop cohesive bridge, whose discAUC reaches 0.73--0.98, on both bipartite and non-bipartite graphs. Motivated by this, we propose HAWKEYE, a cohesion-aware structural channel that incrementally maintains the classical k-family of cohesiveness indicators (degree → k-core → k-truss) and forms 2-hop cohesive-bridge features. HAWKEYE is a drop-in replacement for a temporal-graph model's native structure channel, with no change to the backbone. Swapping HAWKEYE into DyGFormer improves test AP/MRR over the cooccurrence channel by +0.6 to +10.8 points across six multi-seed-validated datasets (uci, enron, USLegis, CanParl, reddit, mooc). On the bipartite recommendation benchmark tgbl-subreddit, a 3-seed single-pass struct-only ablation shows HAWKEYE nearly doubling the baseline test MRR (0.103±0.003 → 0.204±0.005, +10.1 points across all three seeds); the streaming pipeline scales to the 67M-edge tgbl-flight in five minutes per pass. We further characterise when it helps: the gain tracks a graph's training-free 2-hop discAUC and vanishes on degenerate or saturated graphs -- a predictable boundary. All code, data, and figure-generation scripts are released.
Figures & tables
Figure 1. Running example (used throughout the paper). In a corporate email network, Alice ( u ) and Bob ( v ) have never emailed each other, so the 1-hop common-neighbour count is CN=0 ; a cooccurrence-based structure channel sees no signal. Yet two 2-hop paths connect them: Alice–Carol–Dan and Alice–Eve–Grace, where Dan (core 5 ) and Grace (core 4 ) are Bob’s direct neighbours and Carol, Eve are the length-two intermediaries from Alice. Hawkeye reads exactly these bridges and correctly rates Alice–Bob as a likely next-email pair. Section 3 shows this configuration is the typical informative pair on sparse temporal graphs; Section 4 explains how the cache and the slot encoder make Alice’s, Bob’s, and the intermediaries’ coreness available at query time; and § 5.6 returns to this example in the case study.
Table 1. Discriminability AUC of 1-hop vs. 2-hop structural signals (discAUC =0.50 is random). 1-hop CN is random on sparse graphs; the 2-hop cohesive bridge is strongly discriminative.
Figure 2. Hawkeye per-batch timing, threaded with the Alice/Bob running example. Gray boxes are CPU work (Cohesion Cache + slot-feature extraction), blue boxes are GPU work (Cohesion Slot Encoder + unchanged DyGFormer). Orange badges P1–P8 mirror the steps of Algorithm 2 ; the orange feedback arrow is the “predict-then-advance” contract that commits the batch’s edges after they have been scored.
component
time
space
adjacency maintenance
O(1) /edge
O(N+M)
degree update
O(1) /edge
O(N)
core-number update
O(∣S∣) /edge
O(N)
trussness update (opt.)
up to O(m1.5)
O(M)
2-hop bridge extraction
O(dudmax) /query
O(dmax) transient
Cohesion Slot Encoder
O(dfeat⋅ch) /slot
∼103 params
Table 2. Per-edge / per-query overhead of Hawkeye over the backbone. ∣S∣ is the (small) core-affected set; du,dmax are degrees.
dataset
source
nodes
edges
dˉ
type
tgbl-wiki
TGB
9,227
157,474
4.0
bipartite
tgbl-uci
TGB
1,899
59,835
14.6
non-bipartite
tgbl-enron
TGB
184
125,235
24.1
non-bipartite
tgbl-subreddit
TGB
10,984
672,447
14.3
bipartite
tgbl-lastfm
TGB
1,980
1.29 M
156.6
bipartite
tgbl-review
TGB
352,637
4.87 M
26.8
bipartite
Table 3. Dataset statistics used in this paper. Counts are direct from the released edge files. dˉ is the average static degree : distinct neighbours per node over the full stream, dˉ=2∣Estatic∣/∣V∣ — the quantity that governs the sparsity mechanism of § 3 (the 1-hop CN degenerates when dˉ≪∣V∣ ). TGB datasets above the rule are used for the main DyGFormer + Hawkeye results; the lower TGB block lists the large-graph datasets used in the scalability experiments (§ 5.4 ); DGB datasets follow the DyGLib ( 35 ) release.
configuration
uci
enron
CanParl
USLegis
mooc
reddit
DyGFormer (none)
0.838±.001
0.771±.007
0.680±.045
0.715±.005
0.797±.001
0.966±.000
DyGFormer (cooccur)
0.956±.000
0.917±.000
0.708±.008
0.719±.001
0.857±.001
0.975±.014
DyGFormer ( + Hawkeye )
0.942±.004
0.924±.001
0.816±.001
0.768±.004
0.915±.007
0.974±.014
DyGFormer ( ⊕ Hawkeye )
0.962±.001
0.930±.001
0.821±.002
0.770±.003
0.917±.003
0.966±.000
Table 4. Structure-channel swap-in on DyGFormer (DGB protocol, test AP). All entries 3-seed mean ± std under the current code. Bold : best per dataset. tgbl-wiki (TGB MRR) is reported separately in Table 6 .
dataset
edges
baseline
with Hawkeye
gain
tgbl-subreddit
672K
0.103±.003
0.204±.005
+10.1★
tgbl-review
4.87 M
0.283±.002
0.2751
−0.8
tgbl-lastfm
1.29 M
0.008
0.007
≈0
Table 5. Large-graph effectiveness. Single-pass struct-only training, 1 h cap. “Baseline” uses degree only with no pairwise computation; “with Hawkeye ” adds k -core and the 2-hop cohesive bridge. Gain is in test-MRR points.
method
test MRR
TGN †
0.396
TGAT
0.508
DyGFormer (none)
0.537
GraphMixer
0.549
EdgeBank †
0.571
DyGFormer (cooccur)
0.779
Table 6. Comparison on tgbl-wiki (test MRR). † cited from the TGB leaderboard / original papers.
Figure 3. Per-dataset Hawkeye swap-in gain over the DyGFormer (cooccur) baseline (test AP for DGB, test MRR for wiki ); ★ = 3-seed validated (std ≤0.011 ). Double-digit gains on CanParl ( +10.8 ) and tgbl-subreddit ( +10.1 ), mid single-digit on mooc ( +5.8 ) and USLegis ( +4.8 ), small but consistent on sparse uci / enron ; on saturated reddit and degenerate tgbl-lastfm the gain correctly vanishes, tracking the training-free 2-hop discAUC predictor (§ 3 ).
dataset
2-hop discAUC
Hawkeye gain (pts)
reddit
0.98
≈0 (cooccur sat.) ★
tgbl-subreddit
0.96
+10.1★
mooc
0.94
+5.8★
tgbl-wiki
0.85
+2.8 (legacy)
tgbl-uci
0.76
+0.6★
tgbl-enron
0.73
+1.3★
Table 7. Training-free 2-hop discAUC (Table 1 ) vs. measured Hawkeye gain. Direct in the sparse/bipartite regimes; in the near-complete regime ( CanParl , USLegis ) the raw 2-hop count saturates but the trained, core-weighted Hawkeye still wins. ★ 3-seed mean ± std. tgbl-coin and UNvote have discAUC only (no trained gain) and are omitted.
Strategy
uci
mooc
reddit
baseline
1.00×
1.00×
1.00×
pinned + async
1.11×
1.00×
1.04×
prefetcher
1.21×
1.03×
1.07×
prefetch ×2
1.08×
1.00×
1.15×
precompute
3.47×
3.04×
3.16×
Table 8. Wall-clock speedup over the sequential baseline (three simulated epochs of 50 batches). Only precompute is universally robust.
configuration
time / epoch (s)
overhead
DyGFormer (none, no struct.)
5.4
−76%
DyGFormer (cooccur, baseline)
22.4
reference
DyGFormer + Hawkeye (gev, replace)
40.2
+79%
DyGFormer ⊕ Hawkeye (both, add)
57.1
+154%
Table 9. Measured per-epoch wall time on uci (3-seed mean). Overhead is relative to the DyGFormer baseline (cooccur).
Many temporal link predictors summarize past interactions through learned node representations. We examine whether simple counts of recurring interaction patterns can provide competitive predictions without learning these representations. We propose a temporal link predictor based on statistical language modelling. It pools transition and co-occurrence counts across sources to predict links that a source has never formed. We smooth sparse estimates using destination frequencies or Kneser-Ney continuation counts. A shared log-linear rule combines these estimates with popularity, source history, and recency, without node embeddings. In our main evaluation, the model achieves the highest MRR among the compared methods on 7 out of 16 datasets from TGB and TGB-Seq. It also outperforms EdgeBank and Base3 on all 16 datasets and the heuristic family on 14. These gains extend to datasets designed to limit repeated edges. With only 9--13 learned parameters, our model provides a simple and competitive baseline for evaluating future neural temporal link predictors.
Lisi Qarkaxhija, Ingo Scholtes
Chair of Machine Learning for Complex Networks Center for Artificial Intelligence and Data Science (CAIDAS) Julius-Maximilians-Universität Würzburg, DE
Temporal link prediction on the Temporal Graph Benchmark 2.0 (TGB 2.0) faces a scalability ceiling: on the benchmark's three largest datasets, every existing embedding method runs out of memory or exceeds the time budget. These large-scale graphs are the ones nearest real deployment scale, so failing on them is a real production limitation. EdgeReMIND sets the highest reported test mean reciprocal rank (MRR) on six of eight TGB 2.0 datasets and is the only relation-aware method that runs on all of them. This linear memorization model, with learned per-relation weights over data-calibrated features, is therefore not merely a fallback where embeddings fail but a practical state-of-the-art baseline across the benchmark.
Temporal graph data are recorded in different representations, but whether these differences also determine the scope of learned knowledge reuse remains unclear. This study investigates whether predictive structure learned from relational histories can be reused between continuous-time dynamic graphs (CTDGs) and temporal knowledge graphs (TKGs). Bidirectional reuse emerges while retaining distinct input and prediction interfaces and independent vocabularies, and sources with the same representation are not always more useful. Controlled reorganizations of source histories show that the organization contributing to reuse varies across source-target conditions. We show that learned aspects of Relational Dynamics, the predictive structure present in relational histories, can be reused across conventional representation boundaries. Independently pretrained TKG and CTDG learners can also be fused at the score level to improve prediction on a third dataset without entity or relation-semantic alignment. Two proofs of concept in recommendation and security detection illustrate that external temporal sources without direct alignment can also become useful pretraining resources.
Minwoo Yu, Young-guk Ha
M. Yu and Y.-g. Ha are with Smart Computing Laboratory, Department of Computer Science & Engineering, Konkuk University, Seoul 05029, Republic of Korea.