Poster and Film – The Polish School of Poster in the Collections of the Library of Łódź University

Dynamika systematycznego wzrostu, nowoczesna przestrzeń intelektu, labirynt znaków, magia zaangażowanych w swoją pracę ludzi z pasją – to tylko kilka haseł, które przychodzą na myśl, kiedy chcemy przywołać nazwę Biblioteki Uniwersytetu Łódzkiego i 70 lat jej historii. Łódź przed dwoma wiekami powstawała z tradycji niejednorodnych, i podobnie powstawał – jako mozaika różnych treści intelektualnych – Uniwersytet Łódzki.The article presents the collection of posters located in The Special Collection Department in the Library of Łódź University. This collection mainly includes the film posters, but also the theatre, the social, the sports and the circus ones. Some posters were the mainstream of The Polish School of Posters – the phenomenon that influenced post-war fine arts in our country. Their authors were affiliated with the young generation of artists longing to find their own place in new reality. Here, the names of Henryk Tomaszewski, Eryk Lipiński, Tadeusz Trepkowski, and Józef Mroszczak should be mentioned. The Library collection of film posters consists of 2000 items. The article mainly focuses on those that were the mainstream of The Polish School of Poster

Negative Effects of Incentivised Viral Campaigns for Activity in Social Networks

Viral campaigns are crucial methods for word-of-mouth marketing in social communities. The goal of these campaigns is to encourage people for activity. The problem of incentivised and non-incentivised campaigns is studied in the paper. Based on the data collected within the real social networking site both approaches were compared. The experimental results revealed that a highly motivated campaign not necessarily provides better results due to overlapping effect. Additional studies have shown that the behaviour of individual community members in the campaign based on their service profile can be predicted but the classification accuracy may be limited.Comment: In proceedings of the 2nd International Conference on Social Computing and its Applications, SCA 201

Quantifying Social Network Dynamics

The dynamic character of most social networks requires to model evolution of networks in order to enable complex analysis of theirs dynamics. The following paper focuses on the definition of differences between network snapshots by means of Graph Differential Tuple. These differences enable to calculate the diverse distance measures as well as to investigate the speed of changes. Four separate measures are suggested in the paper with experimental study on real social network data.Comment: In proceedings of the 4th International Conference on Computational Aspects of Social Networks, CASoN 201

Effective Influence Spreading in Temporal Networks with Sequential Seeding

The spread of influence in networks is a topic of great importance in many application areas. For instance, one would like to maximise the coverage, limiting the budget for marketing campaign initialisation and use the potential of social influence. To tackle this and similar challenges, more than a decade ago, researchers started to investigate the influence maximisation problem. The challenge is to find the best set of initially activated seed nodes in order to maximise the influence spread in networks. In typical approach we will activate all seeds in single stage, at the beginning of the process, while in this work we introduce and evaluate a new approach for seeds activation in temporal networks based on sequential seeding. Instead of activating all nodes at the same time, this method distributes the activations of seeds, leading to higher ranges of influence spread. The results of experiments performed using real and randomised networks demonstrate that the proposed method outperforms single stage seeding in 71% of cases by nearly 6% on average. Knowing that temporal networks are an adequate choice for modelling dynamic processes, the results of this work can be interpreted as encouraging to apply temporal sequential seeding for real world cases, especially knowing that more sophisticated seed selection strategies can be implemented by using the seed activation strategy introduced in this work.Comment: 11 pages, 10 figures, reproductory code availabl

Hawkes-modeled telecommunication patterns reveal relationship dynamics and personality traits

It is not news that our mobile phones contain a wealth of private information about us, and that is why we try to keep them secure. But even the traces of how we communicate can also tell quite a bit about us. In this work, we start from the calling and texting history of 200 students enrolled in the Netsense study, and we link it to the type of relationships that students have with their peers, and even with their personality profiles. First, we show that a Hawkes point process with a power-law decaying kernel can accurately model the calling activity between peers. Second, we show that the fitted parameters of the Hawkes model are predictive of the type of relationship and that the generalization error of the Hawkes process can be leveraged to detect changes in the relation types as they are happening. Last, we build descriptors for the students in the study by jointly modeling the communication series initiated by them. We find that Hawkes-modeled telecommunication patterns can predict the students' Big5 psychometric traits almost as accurate as the user-filled surveys pertaining to hobbies, activities, well-being, grades obtained, health condition and the number of books they read. These results are significant, as they indicate that information that usually resides outside the control of individuals (such as call and text logs) reveal information about the relationship they have, and even their personality traits