The widespread of Online Social Networks and the opportunity to commercialize popular accounts have attracted a large number of automated programs, known as artificial accounts. This paper focuses on the classification of human and fake accounts on the social network, by employing several graph neural networks, to efficiently encode attributes and network graph features of the account. Our work uses both network structure and attributes to distinguish human and artificial accounts and compares attributed and traditional graph embeddings. Separating complex, human-like artificial accounts into a standalone task demonstrates significant limitations of profile-based algorithms for bot detection and shows the efficiency of network structure-based methods for detecting sophisticated bot accounts. Experiments show that our approach can achieve competitive performance compared with existing state-of-the-art bot detection systems with only network-driven features. The source code of this paper is available at: http://github.com/karpovilia/botdetection.

1. DETECTING AUTOMATICALLY MANAGED
ACCOUNTS IN ONLINE SOCIAL NETWORKS:
GRAPH EMBEDDING APPROACH
Ilia Karpov (karpovilia@gmail.com)
Ekaterina Glazkova (catherine.glazkova@gmail.com)
Moscow, 2020

2. BOT ACCOUNT EXAMPLES
Catch Me if You Can
Detecting Automatically Managed Accounts in OSN

3. DATA COLLECTION
Defining Bot account
Detecting Automatically Managed Accounts in OSN
1.Manual annotation
2.Suspended users lists
3.Honeypots
Existing approaches*
* F. Morstatter et all: A New Approach to Bot Detection: Striking the Balance between Precision and Recall (2016)
A bot is an account created and used to generate profit for the owner by violating the rules of a social network by automatic methods
1.Account exchanges monitoring
2.Suspended users lists
3.Induction based search**
Proposed approach

4. CLASSIFICATION PROBLEM
Profile features
Detecting Automatically Managed Accounts in OSN

5. CLASSIFICATION PROBLEM
Profile model
Detecting Automatically Managed Accounts in OSN
• country_id
• personal_people_main
• city_title
• sex
• personal_langs
• counters_gifts
• mobile_phone
• counters_pages
• personal_alcohol
• is_closed
• last_seen_platform
• home_phone
• relation_partner_first_name
• relation
• counters_followers
• domain
• occupation_id
• counters_subscriptions
• personal_smoking
• movies
• occupation_name
• counters_photos
• counters_videos
• city_id
• bdate
• university
• counters_audios
• last_seen_time
• faculty
• counters_user_photos
• counters_groups
• has_photo
Selected static features Selected network features
• friend_id

6. EMBEDDING GENERATION
Node2Vec
Detecting Automatically Managed Accounts in OSN
* A. Grover: node2vec: Scalable Feature Learning for Networks (2016)

7. EMBEDDING GENERATION
Attri2Vec
Detecting Automatically Managed Accounts in OSN
* Zhang et al: Attributed network embedding via subspace discovery (2019)

8. Detecting Automatically Managed Accounts in OSN
p = 0.25 p = 0.5 p = 1 p = 2 p = 4
q = 0.25 0.727 0.823 0.751 0.753 0.793
q = 0.5 0.750 0.795 0.796 0.806 0.754
q = 1 0.771 0.804 0.765 0.788 0.772
q = 2 0.747 0.742 0.808 0.764 0.779
q = 4 0.776 0.724 0.745 0.709 0.793
p = 0.25 p = 0.5 p = 1 p = 2 p = 4
q = 0.25 0.856 0.814 0.804 0.823 0.780
q = 0.5 0.787 0.768 0.813 0.799 0.822
q = 1 0.863 0.812 0.847 0.829 0.808
q = 2 0.821 0.931 0.776 0.793 0.848
CLASSIFICATION PROBLEM
LogReg Classification ROC AUC based on N2V embedding
Sophisticated accounts
Technical accounts

9. Detecting Automatically Managed Accounts in OSNCLASSIFICATION PROBLEM
Classification ROC AUC
Technical accounts Sophisticated accounts
Attri2Vec 0.988 0.684
Node2Vec 0.93 0.87
Static 0.85 0.81
N2V + SF 0.934 0.91
• Support Vector Classifier (SVC)
• Random Forest (RF)
• Logistic Regression (LogReg)
Classifiers evaluation
Model results

10. Detecting Automatically Managed Accounts in OSNCLASSIFICATION PROBLEM
Comparison with existing approaches
Technical accounts Sophisticated accounts
AUC ROC 0.988 0.867
Zegzhda et.al. --- 0.73
Skorniakov et.al. --- 0.820
• Two bot detection datasets with anonymised data *
• More than 80 network embedding trainings with different parameters.
• Classifiers on embeddings obtained with network embedding.
• Classifiers based on static features.
• Classifiers on the concatenation of static features and embeddings.
Contributions
* https://github.com/karpovilia/botdetection

11. Detecting Automatically Managed Accounts in OSN
FUTURE RESEARCH
• use of text embedding - a significant part of artificial accounts performs the
function of promoting certain goods or disseminating information, which can be
used for classification;
• significant number of accounts hide their friends, but leave open groups that can
be used to model a user as a bipartite graph node;
• network modeling as a temporal network is of interest, taking into account such
characteristics as the joint appearance of accounts on the network

12. Questions?
Ilia Karpov (karpovilia@gmail.com)
Ekaterina Glazkova (catherine.glazkova@gmail.com)