Organizations: Fraunhofer IAIS, Sankt Augustin, Germany · University of Bonn, Germany · Lamarr Institute for Machine Learning and Artificial Intelligence, Germany · PhenoRob Cluster of Excellence, University of Bonn, Germany
Raw player input sequences in video games contain fine-grained behavior, but are high-dimensional and noisy, which makes large-scale analytics challenging. To address this, we introduce PlayerEmbed, a framework that learns compact and discriminative player embeddings using deep metric learning. Our approach uses a hybrid CNN-LSTM encoder trained on raw input sequences from 1,000 players. We evaluate the model on held-out sequences from these players and on sequences from 1,000 players entirely unseen during training to assess generalization to unseen identities. For player identification, a nearest-centroid classifier built from reference embeddings achieves strong performance, reaching balanced accuracies of 0.950 for players seen during training and 0.879 for players unseen during training. Systematically increasing the number of training players substantially improves generalization to unseen players, indicating a transition from simple fingerprinting to learning transferable behavioral patterns.
Figures & tables
Fig. 1: Flowchart of how the PlayerEmbed framework can be used for player identification using nearest-centroid classification.
Config
M
Centroid
Medoid
1-NN
5-NN
9-NN
K → K
1
0.790 ± .007
0.720 ± .010
0.742 ± .008
0.743 ± .008
0.740 ± .008
K → K
3
0.931 ± .004
0.889 ± .005
0.889 ± .004
0.886 ± .004
0.881 ± .004
K → K
6
0.950 ± .003
0.920 ± .004
0.917 ± .004
0.913 ± .004
0.908 ± .004
KU → U
1
0.621 ± .008
0.520 ± .008
0.599 ± .007
0.598 ± .007
0.601 ± .007
KU → U
3
0.833 ± .004
0.728 ± .006
0.775 ± .005
0.782 ± .005
0.783 ± .004
KU → U
6
0.879 ± .004
0.792 ± .007
0.827 ± .005
0.832 ± .005
0.831 ± .005
TABLE I: Balanced accuracy of classification methods across evaluation configs and averaging levels M for n=1000 .
Balanced Accuracy
Macro F1
Config
n
M=1
M=6
M=1
M=6
K → K
100
0.8990 ± .009
0.9998 ± .000
0.8985 ± .009
0.9998 ± .000
K → K
200
0.8993 ± .004
0.9996 ± .000
0.8977 ± .004
0.9996 ± .000
K → K
400
0.8900 ± .006
0.9967 ± .001
0.8825 ± .006
0.9964 ± .001
K → K
600
0.8564 ± .007
0.9851 ± .004
0.8407 ± .008
0.9826 ± .005
K → K
800
0.8281 ± .009
0.9704 ± .005
0.8015 ± .009
0.9641 ± .006
TABLE II: Balanced accuracy and macro F1 for nearest-centroid classification across evaluation configurations, numbers of known training players n , and averaging levels M .
n=100
n=1000
Method
M=1
M=6
M=1
M=6
MLP
0.5522 ± .0060
0.7633 ± .0068
0.2513 ± .0015
0.3946 ± .0082
SVM
0.4407 ± .0024
0.7951 ± .0077
0.1332 ± .0013
0.3549 ± .0042
Centroid
0.3197 ± .0040
0.7566 ± .0072
0.1226 ± .0006
0.3701 ± .0056
XGBoost
0.5418 ± .0049
0.7124 ± .0055
0.2200 ± .0026
0.3148 ± .0053
PlayerEmbed
0.8990 ± .0090
0.9998 ± .0000
0.7899 ± .0070
0.9503 ± .0030
TABLE III: Balanced accuracy of traditional baselines compared to PlayerEmbed . Bold marks the best baseline.
Model
K → K
KU → U
M=1
M=6
M=1
M=6
CNN-LSTM
0.790 ± .007
0.950 ± .003
0.621 ± .008
0.879 ± .004
Transformer L=3
0.698 ± .005
0.931 ± .002
0.385 ± .010
0.785 ± .006
CNN-LSTM no head
0.702 ± .017
0.921 ± .009
0.524 ± .018
0.846 ± .009
Transformer L=2
0.681 ± .004
0.921 ± .002
0.444 ± .009
0.803 ± .003
LSTM
0.680 ± .027
0.914 ± .009
0.506 ± .020
0.830 ± .012
TABLE IV: Balanced accuracy for n=1000 on known and unknown players across averaging levels M . Rows are ordered by known-player performance at M=6 .
Fig. 2: UMAP visualization of player centroids for KTest and UTest with HDBSCAN cluster assignments.