Ju Yong Lee, Innopolis University - on user reputation, measuring trust and data security in social networks

Ju Young Lee - Head of the Laboratory of Network Science and Information Technology at Innopolis University, Associate Professor.

Received a PhD from Syracuse University(USA). He has experience in university and industry (JPMorgan, Sun Microsystems). Professor Lee is developing algorithms for determining the activity and reputation of social network users. Her research focuses on the reputation of distributed computing and the assessment of the degree of nodes in a social network.

Reputation: virtual and real

Reputation is the perception of the user by other people. In real life, this happens everywhere. Whether you suspect it or not, when you first meet a person you have certain expectations or forebodings about him. Then, in the process of speaking or interacting, you update this presentation. All these factors are included in the reputation.

Reputation is not only about people, but also about companies, government organizations and any structures with which we interact. I rarely use social networks and I know only the mostPopular: Facebook and Instagram. In them, people communicate with comments and photos. The concept of reputation on these popular sites is not so widely used, since most of the interactions there are interpersonal. On Facebook, we do not open a bank deposit, do not make deals, and do not manage finances. In a broad sense, we do not need much trust for communication on these platforms, because if our interlocutor turns out to be a bad person, we will not lose much.

The reputational system is mainly used on commercial sites such as Amazon and eBay in the USA or Ozon and Yandex.Market in Russia. Here you need trust between the seller andby the buyer. If you pay money and the goods are not sent, you lose something. Therefore, reputation and trust are important for economic reasons. Usually on these platforms use a centralized reputation system, which you probably know. For example, Amazon has a five-star rating system, where you can write to the seller after receiving the goods and give a rating. This is one of the most common reputation systems. It is centralized because it takes control of the algorithm. If you set three stars, and then someone else - four or five, the system will automatically average these values ​​and show the result to other users. This type of assessment is very effective for commercial sites.

There are also decentralized or distributed reputation systems. They are applied where there is no centralauthority, for example, in peer-to-peer file-sharing systems. There is no authority that tells you about the reputation of another user. But everyone has their own idea of ​​this or that person. Perhaps I interacted with a user who did not send me a file or has a very slow connection. And the other could have a very pleasant interaction experience with him. So we have different ideas about this person and his reputation is not the average of our arithmetic opinions.

I'm trying to figure out which algorithms are used in popular networks. For example, Stack Overflow or Quora (popularquestion and answer systems - “Hightech”). You ask a question to them, and then people answer it. If the answer becomes more popular, the author increases the reputation. This is a general scheme, but each platform uses different algorithms. Usually their scheme is based on feedback between user interactions: if the interaction is successful, the reputation grows, otherwise it decreases.

We recently developed an algorithm that is completely independent of this type of feedback. The only thing we use is time andinteraction frequency. How often we interact really affects reputation. It does not matter whether it is good communication or not, the main thing is its number and frequency. We compared our development with the standard Stack Overflow algorithm on a single data set. It turned out that their results are very similar. This means that without knowledge of the perception of the user by other participants, one can quite accurately determine his reputation.

AI, fake accounts and agitation

Recently, social networks have become important because of the huge number of registered users. Now have political parties and commercialorganizations, a new channel of influence on all these people. Previously, if any company wanted to promote a product, it used commercials on TV or banners on the side of the road. But since social networks have become popular, everyone has realized that advertising in them is much more effective. To build marketing within the social network is cheaper, and information spreads much faster. Now it’s enough to create a little news instead of buying an expensive movie on TV.

The main role in the popularization of social platforms was played by the younger generation. When I was younger, I hated reading newspapers andother press. In social networks everything is different. If someone says that something interesting is happening, the rumor will spread very quickly. Therefore, social networks and replaced traditional newspapers and magazines.

Now AI can create a fake account and conduct its own activity. Since social platforms have become importantinformation medium, they are used to influence people for political purposes. With their help, parties try to lure people to their side. To do this, they transmit a sample of information that is beneficial to them. This is implemented using AI and learning algorithms. It is important to choose a suitable group of people. If you want to be voted for you, you need to choose the right person. They should not be your ardent opponent or supporter. This may have the opposite effect. It is necessary to choose people "on the border" who can change their opinion. And, of course, such people are easy to identify based on their interests and interactions in social networks.

Surveillance in social networks, Korea and the vulnerability of personal data

On large media and social platforms it is impossible to avoid information leaks. Because, first, you put it there. Secondly, even if large companies like Facebook claim to not share your information, their long and confusing user agreement, which no one actually reads, will allow this to happen.

The main problem in the scandal with Cambridge Analytica is that the analytic company gained access to friends and all friends' data. They developed an application that definedpolitical views of users. Facebook was supposed to provide information only about the people who used it. Although even if the leak did not take place, there are many algorithms that would allow to draw a conclusion about the entire network, based on data on its part.

The transfer of information to third parties is not something new or rare. Facebook is a company, not NPOs, and it needsget a profit. For this we have to share some of the information with other companies. How exactly she does it, how much and what information she gives, nobody knows. So the user must be aware of this danger from the very beginning. Everything related to social platforms has appeared recently. Therefore, the government does not know how to respond to such scandals. Relevant policies are yet to be developed. Now the only person who can protect your data is yourself. I do not want to say that you should not use social networks. They are very convenient and allow you to find new friends. But completely prohibit the transfer of information to third parties will not work - it will happen all the time. Therefore, we need the right approach to this kind of situation - not at the individual, but at the government level.

In Korea, there is a very popular KakaoTalk messenger. Many thought the state was lookingthe history of correspondence in it to find out how people relate to the current government. At that time, some of my friends refused to use certain words. They distorted names and words to avoid observation. I think in many countries the government really does that. Of course, not recognizing publicly, because it is illegal. However, can the government effectively use this information? If you accuse someone on the basis of a photograph from a personal chat, then you must admit that you illegally watched this person. We never know what is actually happening in intra-government structures. At the individual level, there is no way to change the situation.

Having enough information you can find out everything about a person, if you need it. The same case with Cambridge Analytica: they only developed an application - a small psychological test that makes a conclusion about a person on the basis of several questions. This allowed them to identify the political data of the respondents and to use it in the election race. Knowing where you live, what university you went to, you can determine your entire cultural background. Even owning a small amount of information: who are you talking to, who is friends with your friends - can we conclude about so many things. That is why user information in social networks has become critical.