OpenNE: An open source toolkit for Network Embedding

This repository provides a standard NE/NRL(Network Representation Learning）training and testing framework. In this framework, we unify the input and output interfaces of different NE models and provide scalable options for each model. Moreover, we implement typical NE models under this framework based on tensorflow, which enables these models to be trained with GPUs.

We develop this toolkit according to the settings of DeepWalk. The implemented or modified models include DeepWalk, LINE, node2vec, GraRep, TADW and GCN. We will implement more representative NE models continuously according to our released NRL paper list. Specifically, we welcome other researchers to contribute NE models into this toolkit based on our framework. We will announce the contribution in this project.

Requirements

• numpy==1.13.1
• networkx==2.0
• scipy==0.19.1
• tensorflow==1.3.0
• gensim==3.0.1
• scikit-learn==0.19.0

Usage

General Options

You can check out the other options available to use with OpenNE using:

python src/main.py --help

• --input, the input file of a network;
• --graph-format, the format of input graph, adjlist or edgelist;
• --output, the output file of representation;
• --representation-size, the number of latent dimensions to learn for each node; the default is 128
• --method, the NE model to learn, including deepwalk, line, node2vec, grarep, tadw and gcn;
• --directed, treat the graph as directed; this is an action;
• --weighted, treat the graph as weighted; this is an action;
• --label-file, the file of node label; ignore this option if not testing;
• --clf-ratio, the ratio of training data for node classification; the default is 0.5;
• --epochs, the training epochs of LINE and GCN; the default is 5;

Example

To run "node2vec" on BlogCatalog network and evaluate the learned representations on multi-label node classification task, run the following command in the home directory of this project:

python src/main.py --method node2vec --label-file data/blogCatalog/bc_labels.txt --input data/blogCatalog/bc_adjlist.txt --graph-format adjlist --output vec_all.txt --q 0.25 --p 0.25

To run "gcn" on Cora network and evaluate the learned representations on multi-label node classification task, run the following command in the home directory of this project:

python src/main.py --method gcn --label-file data/cora/cora_labels.txt --input data/cora/cora_edgelist.txt --graph-format edgelist --feature-file data/cora/cora.features  --epochs 200 --output vec_all.txt --clf-ratio 0.1

Specific Options

DeepWalk and node2vec:

• --number-walks, the number of random walks to start at each node; the default is 10;
• --walk-length, the length of random walk started at each node; the default is 80;
• --workers, the number of parallel processes; the default is 8;
• --window-size, the window size of skip-gram model; the default is 10;
• --q, only for node2vec; the default is 1.0;
• --p, only for node2vec; the default is 1.0;

LINE:

• --negative-ratio, the default is 5;
• --order, 1 for the 1st-order, 2 for the 2nd-order and 3 for 1st + 2nd; the default is 3;
• --no-auto-stop, no early stop when training LINE; this is an action; when training LINE, we will calculate micro-F1 every epoch. If current micro-F1 is smaller than the last micro-F1, the training process will stop early.

GraRep:

• --kstep, use k-step transition probability matrix（make sure representation-size%k-step == 0).

TADW:

• --lamb, lamb is a hyperparameter in TADW that controls the weight of regularization terms.

GCN:

• --feature-file, The file of node features;
• --epochs, the training epochs of GCN; the default is 5;
• --dropout, dropout rate;
• --weight-decay, weight for l2-loss of embedding matrix;
• --hidden, number of units in the first hidden layer.

Input

The supported input format is an edgelist or an adjlist:

edgelist: node1 node2 <weight_float, optional>
adjlist: node n1 n2 n3 ... nk

The graph is assumed to be undirected and unweighted by default. These options can be changed by setting the appropriate flags.

If the model needs additional features, the supported feature input format is as follow (feature_i should be a float number):

node feature_1 feature_2 ... feature_n

Output

The output file has n+1 lines for a graph with n nodes. The first line has the following format:

num_of_nodes dim_of_representation

The next n lines are as follows:

node_id dim1 dim2 ... dimd

where dim1, ... , dimd is the d-dimensional representation learned by OpenNE.

Evaluation

If you want to evaluate the learned node representations, you can input the node labels. It will use a portion (default: 50%) of nodes to train a classifier and calculate F1-score on the rest dataset.

The supported input label format is

node label1 label2 label3...

Comparisons with other implementations

Running environment:
BlogCatalog: CPU: Intel(R) Xeon(R) CPU E5-2620 v3 @ 2.40GHz.
Wiki, Cora: CPU: Intel(R) Core(TM) i5-7267U CPU @ 3.10GHz.

We show the node classification results of various methods in different datasets. We set representation dimension to 128, kstep=4 in GraRep.

Note that, both GCN(a semi-supervised NE model) and TADW need additional text features as inputs. Thus, we evaluate these two models on Cora in which each node has text information. We use 10% labeled data to train GCN.

BlogCatalog: 10312 nodes, 333983 edges, 39 labels, undirected:

• data/blogCatalog/bc_adjlist.txt
• data/blogCatalog/bc_edgelist.txt
• data/blogCatalog/bc_labels.txt

Algorithm	Time	Micro-F1	Macro-F1
DeepWalk	271s	0.385	0.238
LINE 1st+2nd	2008s	0.398	0.235
Node2vec	2623s	0.404	0.264
GraRep	-	-	-
OpenNE(DeepWalk)	986s	0.394	0.249
OpenNE(LINE 1st+2nd)	943s	0.368	0.192
OpenNE(node2vec)	3501s	0.405	0.275
OpenNE(GraRep)	4178s	0.393	0.230

Wiki: 2405 nodes, 17981 edges, 19 labels, directed:

• data/wiki/Wiki_edgelist.txt
• data/wiki/Wiki_category.txt

Algorithm	Time	Micro-F1	Macro-F1
DeepWalk	52s	0.669	0.560
LINE 2nd	70s	0.576	0.387
node2vec	32s	0.651	0.541
GraRep	19.6s	0.633	0.476
OpenNE(DeepWalk)	42s	0.658	0.570
OpenNE(LINE 2nd)	95s	0.629	0.465
OpenNE(Node2vec)	33s	0.655	0.538
OpenNE(GraRep)	23.7s	0.649	0.507

cora: 2708 nodes, 5429 edges, 7 labels, directed:

• data/cora/cora_edgelist.txt
• data/cora/cora.features
• data/cora/cora_labels.txt

Algorithm	Dropout	Weight_decay	Hidden	Dimension	Time	Accuracy
TADW	-	-	-	80*2	13.9s	0.780
GCN	0.5	5e-4	16	-	4.0s	0.790
OpenNE(TADW)	-	-	-	80*2	20.8s	0.791
OpenNE(GCN)	0.5	5e-4	16	-	5.5s	0.789
OpenNE(GCN)	0	5e-4	16	-	6.1s	0.779
OpenNE(GCN)	0.5	1e-4	16	-	5.4s	0.783
OpenNE(GCN)	0.5	5e-4	64	-	6.5s	0.779

Citing

If you find OpenNE is useful for your research, please consider citing the following papers:

@InProceedings{perozzi2014deepwalk,
  Title                    = {Deepwalk: Online learning of social representations},
  Author                   = {Perozzi, Bryan and Al-Rfou, Rami and Skiena, Steven},
  Booktitle                = {Proceedings of KDD},
  Year                     = {2014},
  Pages                    = {701--710}
}

@InProceedings{tang2015line,
  Title                    = {Line: Large-scale information network embedding},
  Author                   = {Tang, Jian and Qu, Meng and Wang, Mingzhe and Zhang, Ming and Yan, Jun and Mei, Qiaozhu},
  Booktitle                = {Proceedings of WWW},
  Year                     = {2015},
  Pages                    = {1067--1077}
}

@InProceedings{grover2016node2vec,
  Title                    = {node2vec: Scalable feature learning for networks},
  Author                   = {Grover, Aditya and Leskovec, Jure},
  Booktitle                = {Proceedings of KDD},
  Year                     = {2016},
  Pages                    = {855--864}
}

@article{kipf2016semi,
  Title                    = {Semi-Supervised Classification with Graph Convolutional Networks},
  Author                   = {Kipf, Thomas N and Welling, Max},
  journal                  = {arXiv preprint arXiv:1609.02907},
  Year                     = {2016}
}

@InProceedings{cao2015grarep,
  Title                    = {Grarep: Learning graph representations with global structural information},
  Author                   = {Cao, Shaosheng and Lu, Wei and Xu, Qiongkai},
  Booktitle                = {Proceedings of CIKM},
  Year                     = {2015},
  Pages                    = {891--900}
}

@InProceedings{yang2015network,
  Title                    = {Network representation learning with rich text information},
  Author                   = {Yang, Cheng and Liu, Zhiyuan and Zhao, Deli and Sun, Maosong and Chang, Edward},
  Booktitle                = {Proceedings of IJCAI},
  Year                     = {2015}
}

@Article{tu2017network,
  Title                    = {Network representation learning: an overview},
  Author                   = {TU, Cunchao and YANG, Cheng and LIU, Zhiyuan and SUN, Maosong},
  Journal                  = {SCIENTIA SINICA Informationis},
  Volume                   = {47},
  Number                   = {8},
  Pages                    = {980--996},
  Year                     = {2017}
}

Sponsor

This research is supported by NSFC and Tencent.