Empirical Study of User Preferences Based on Rating Data of Movies.

User preference plays a prominent role in many fields, including electronic commerce, social opinion, and Internet search engines. Particularly in recommender systems, it directly influences the accuracy of the recommendation. Though many methods have been presented, most of these have only focused on how to improve the recommendation results. In this paper, we introduce an empirical study of user preferences based on a set of rating data about movies. We develop a simple statistical method to investigate the characteristics of user preferences. We find that the movies have potential characteristics of closure, which results in the formation of numerous cliques with a power-law size distribution. We also find that a user related to a small clique always has similar opinions on the movies in this clique. Then, we suggest a user preference model, which can eliminate the predictions that are considered to be impracticable. Numerical results show that the model can reflect user preference with remarkable accuracy when data elimination is allowed, and random factors in the rating data make prediction error inevitable. In further research, we will investigate many other rating data sets to examine the universality of our findings

SIS dynamic network model based on product semantics from the perspective of infectious disease dynamics

Recommendation system is unable to achive the optimal algorithm, recommendation system precision problem into bottleneck. Based on the perspective of product marketing, paper takes the inherent attribute as the classification standard and focuses on the core problem of “matching of product classification and recommendation algorithm of users’ purchase demand”. Three hypotheses are proposed: (1) inherent attributes of the product directly affect user demand; (2) classified product is suitable for different recommendation algorithms; (3) recommendation algorithm integration can achieve personalized customization. Based on empirical research on the relationship between characteristics of recommendation information (independent variable) and purchase intention (dependent variable), it is concluded that predictability and difference of recommendation information are not fully perceived and stimulation is insufficient. Therefore, SIS dynamic network model based on the distribution model of SIS virus is constructed. It discusses the spreading path of recommendation information and “infection” situation of consumers to enhance accurate matching of recommendation system

Prevention of Burnout Syndrom among Early Intervention Advisors

The bachelor thesis deals with the issue of prevention of burnout syndrome, what are the possibilities and methods that can be used in the context of personality and organization. The possibilities and methods of prevention of burnout syndrome were investigated on early care advisors in the Early Care Kuk, located in Pilsen. This document is conceived in two parts, theoretical and practical. The aim of the work was to find out which areas of prevention of burnout syndrome are priority for the early care advisors of the given center. The theoretical part describes the issue of burnout syndrome. It defines the term of burnout syndrome, vulnerable groups of people, it also deals with the risk factors that contribute to the burnout syndrome and describes the most frequent signs, symptoms and phases that are typical for the burnout syndrome. Subsequently, in the theoretical part is located a chapter on prevention at the level of personality and prevention at the organization level. The last chapter of the theoretical part is focused on early care, explanation of the concept, definition of rights and duties of early care advisors and the current state of early care in the Czech Republic. The practical part is elaborated in the form of qualitative research. In the survey were used the polling method and the interview technique according to the instructions. The survey was attended by 3 informants who were selected according to the quota selection method. The data obtained from the interviews was evaluated by the clustering method. Research has shown that early care advisors of the given center are familiar with the problematics of burnout syndrome and its prevention. Prevention options at the personality level are used individually. At the organization level, they use prevention options mainly in the form of supervision, intervision and further education. The research also showed that early care advisors of the given center perceive good workplace relationships and mutual support and respect as a key components of burnout syndrome prevention

Hyper-network in which user is treated as node and movie as hyper-edge.

<p>Hyper-network in which user is treated as node and movie as hyper-edge.</p

The distribution of distance between movies.

<p>The distribution of distance between movies.</p

Exploring the Association between Oxygen Concentration and Life Expectancy in China: A Quantitative Analysis

The aim of this study was to investigate and quantify the association between oxygen concentration and life expectancy. The data from 34 provinces and 39 municipalities were included in all analyses. Bayesian regression modeling with spatial-specific random effects was used to quantify the impact of oxygen concentration (measured as partial pressure of oxygen) on life expectancy, adjusting for other potential confounding factors. We used hierarchical cluster analysis to group the provinces according to disease burden and analyzed the oxygen levels and the characteristics of causes of death between the clusters. The Bayesian regression analysis showed that the life expectancy at the provincial level increased by 0.15 (95% CI: 0.10–0.19) years, while at the municipal level, it increased by 0.17 (95% CI: 0.12–0.22) years, with each additional unit (mmHg) of oxygen concentration, after controlling for potential confounding factors. Three clusters were identified in the hierarchical cluster analysis, which were characterized by different oxygen concentrations, and the years of life lost from causes potentially related to hypoxia were statistically significantly different between the clusters. A positive correlation was found between oxygen concentration and life expectancy in China. The differences in causes of death and oxygen levels in the provincial clusters suggested that oxygen concentration may be an important factor in life expectancy when mediated by diseases that are potentially related to hypoxia

Difference between predicting value and its real value vs. average distance between movies.

<p>Difference between predicting value and its real value vs. average distance between movies.</p

The number of predictable ratings vs. <i>k</i> value.

<p>The number of predictable ratings vs. <i>k</i> value.</p