National Research University – Higher School of Economics

About: National Research University – Higher School of Economics is a education organization based out in Moscow, Russia. It is known for research contribution in the topics: Population & Computer science. The organization has 12873 authors who have published 23376 publications receiving 256396 citations.

An SEM Approach to Continuous Time Modeling of Panel Data: Relating Authoritarianism and Anomia

Abstract: Panel studies, in which the same subjects are repeatedly observed at multiple time points, are among the most popular longitudinal designs in psychology. Meanwhile, there exists a wide range of different methods to analyze such data, with autoregressive and cross-lagged models being 2 of the most well known representatives. Unfortunately, in these models time is only considered implicitly, making it difficult to account for unequally spaced measurement occasions or to compare parameter estimates across studies that are based on different time intervals. Stochastic differential equations offer a solution to this problem by relating the discrete time model to its underlying model in continuous time. It is the goal of the present article to introduce this approach to a broader psychological audience. A step-by-step review of the relationship between discrete and continuous time modeling is provided, and we demonstrate how continuous time parameters can be obtained via structural equation modeling. An empirical example on the relationship between authoritarianism and anomia is used to illustrate the approach.

Software risk management

Abstract: Modern software development faces many challenges nowadays In order to avoiding, minimizing, and monitoring the risks and their impact, it is important to identify, estimate and evaluate the risks The study addresses software risk management in software development area An approach to analysis, structuring, and usage is proposed for the information technology (IT) projects in the risk management context It is based on the study of the existing theoretical knowledge and practices and examples of better management The author provides recommendations on software risk management and gives a brief overview of the automated software tools

Topic modelling for qualitative studies

Abstract: Qualitative studies, such as sociological research, opinion analysis and media studies, can benefit greatly from automated topic mining provided by topic models such as latent Dirichlet allocation LDA. However, examples of qualitative studies that employ topic modelling as a tool are currently few and far between. In this work, we identify two important problems along the way to using topic models in qualitative studies: lack of a good quality metric that closely matches human judgement in understanding topics and the need to indicate specific subtopics that a specific qualitative study may be most interested in mining. For the first problem, we propose a new quality metric, tf-idf coherence, that reflects human judgement more accurately than regular coherence, and conduct an experiment to verify this claim. For the second problem, we propose an interval semi-supervised approach ISLDA where certain predefined sets of keywords that define the topics researchers are interested in are restricted to specific intervals of topic assignments. Our experiments show that ISLDA is better for topic extraction than LDA in terms of tf-idf coherence, number of topics identified to predefined keywords and topic stability. We also present a case study on a Russian LiveJournal dataset aimed at ethnicity discourse analysis.

On stability of a formal concept

Abstract: In this paper we define and analyze stability of a formal concept. A stability index is based on the idea of a dependency in a dataset that can be reconstructed from different parts of the dataset. This idea, underlying various methods of estimating scientific hypotheses, is used here for estimating concept-based hypotheses. Combinatorial properties of stability indices, algorithmic comlpexity of their computation, as well as their dynamics with arrival of new examples are studied.