While recommendation plays an increasingly critical role in our living, study, work, and entertainment, the recommendations we receive are often for irrelevant, duplicate, or uninteresting products and ser- vices. A c...While recommendation plays an increasingly critical role in our living, study, work, and entertainment, the recommendations we receive are often for irrelevant, duplicate, or uninteresting products and ser- vices. A critical reason for such bad recommendations lies in the intrinsic assumption that recommend- ed users and items are independent and identically distributed （liD） in existing theories and systems. Another phenomenon is that, while tremendous efforts have been made to model specific aspects of users or items, the overall user and item characteristics and their non-IIDness have been overlooked. In this paper, the non-liD nature and characteristics of recommendation are discussed, followed by the non-liD theoretical framework in order to build a deep and comprehensive understanding of the in- trinsic nature of recommendation problems, from the perspective of both couplings and heterogeneity. This non-liD recommendation research triggers the paradigm shift from lid to non-liD recommendation research and can hopefully deliver informed, relevant, personalized, and actionable recommendations. It creates exciting new directions and fundamental solutions to address various complexities including cold-start, sparse data-based, cross-domain, group-based, and shilling attack-related issues.展开更多
Strengthen the practical teaching is an important way to improve effectiveness of colleges＇ ideological and political lessons. It has an important role to stimulate the students＇ individuality development, cultivate...Strengthen the practical teaching is an important way to improve effectiveness of colleges＇ ideological and political lessons. It has an important role to stimulate the students＇ individuality development, cultivate students＇ innovative spirit, help students improve their ability of analyzing and solving problems, and improve students＇ comprehensive quality. This paper will analyze the problems existing in practical teaching model of ideological and political lessons, and put forward the corresponding reform measures, hoping to innovate and perfect the practical teaching model.展开更多
Sufferers of breast cancer are often plagued by various psychological problems. Mastectomy, which has a serious influence on the female sex characteristics, can bring about especially serious psychological problems. T...Sufferers of breast cancer are often plagued by various psychological problems. Mastectomy, which has a serious influence on the female sex characteristics, can bring about especially serious psychological problems. These problems affect not only the patients’ quality of life but also the beginning, development, and end of the disease. This paper reviewed the relationships between the patients’ personal factors, the disease itself, treatment factors, and other socio-psychological factors and psychological conditions so as to provide new ideas for the psychological intervention on breast cancer patients, comprehensive clinical diagnosis and treatment, and prevention and cure.展开更多
Teaching content of Higher Mathematics is systematic and rigor with a high degree of abstraction. Because different students are on the different basis and different disciplines have various requirements, mathematics ...Teaching content of Higher Mathematics is systematic and rigor with a high degree of abstraction. Because different students are on the different basis and different disciplines have various requirements, mathematics is generally difficult for students. In order to improve the quality of teaching mathematics, we should make use of individualized teaching and teaching by different levels in order to achieve the best teaching results.展开更多
The process of dispersal is determined by the interaction of individual （intrinsic） traits and environmental （extrinsic） factors. Although many studies address and quantify dispersal, few evaluate both intrinsic a...The process of dispersal is determined by the interaction of individual （intrinsic） traits and environmental （extrinsic） factors. Although many studies address and quantify dispersal, few evaluate both intrinsic and extrinsic factors jointly. We test the relative importance of intrinsic traits （exploration tendency and size） and extrinsic factors （population density and habitat quality） on dispersal of a medium-sized western United States minnow, southern leatherside chub Lepidomeda aliciae. A generalized linear model with a binomial response was used to determine the probability of individuals dispersing one year after tagging. Medium-sized individuals that were more prone to explore novel environments were 10.7 times more likely to be recaptured outside of their original capture area after a year （dispersal） compared to non-explorer individuals of the same size class. Differences be- tween explorer classifications within the small and large size classes were negligible. Open habitat within 50 m upstream also in- creased the probability of dispersal relative to controls. Relative location within the study reach, and population density were not significantly related to dispersal probabilities of individuals. Our results indicate that understanding of personality may illuminate patterns of dispersal within and among populations展开更多
In this paper, based on spline approximation, the authors propose a unified variable selection approach for single-index model via adaptive L1 penalty. The calculation methods of the proposed estimators are given on t...In this paper, based on spline approximation, the authors propose a unified variable selection approach for single-index model via adaptive L1 penalty. The calculation methods of the proposed estimators are given on the basis of the known lars algorithm. Under some regular conditions, the authors demonstrate the asymptotic properties of the proposed estimators and the oracle properties of adaptive LASSO(aL ASSO) variable selection. Simulations are used to investigate the performances of the proposed estimator and illustrate that it is effective for simultaneous variable selection as well as estimation of the single-index models.展开更多
文摘While recommendation plays an increasingly critical role in our living, study, work, and entertainment, the recommendations we receive are often for irrelevant, duplicate, or uninteresting products and ser- vices. A critical reason for such bad recommendations lies in the intrinsic assumption that recommend- ed users and items are independent and identically distributed （liD） in existing theories and systems. Another phenomenon is that, while tremendous efforts have been made to model specific aspects of users or items, the overall user and item characteristics and their non-IIDness have been overlooked. In this paper, the non-liD nature and characteristics of recommendation are discussed, followed by the non-liD theoretical framework in order to build a deep and comprehensive understanding of the in- trinsic nature of recommendation problems, from the perspective of both couplings and heterogeneity. This non-liD recommendation research triggers the paradigm shift from lid to non-liD recommendation research and can hopefully deliver informed, relevant, personalized, and actionable recommendations. It creates exciting new directions and fundamental solutions to address various complexities including cold-start, sparse data-based, cross-domain, group-based, and shilling attack-related issues.
文摘Strengthen the practical teaching is an important way to improve effectiveness of colleges＇ ideological and political lessons. It has an important role to stimulate the students＇ individuality development, cultivate students＇ innovative spirit, help students improve their ability of analyzing and solving problems, and improve students＇ comprehensive quality. This paper will analyze the problems existing in practical teaching model of ideological and political lessons, and put forward the corresponding reform measures, hoping to innovate and perfect the practical teaching model.
文摘Sufferers of breast cancer are often plagued by various psychological problems. Mastectomy, which has a serious influence on the female sex characteristics, can bring about especially serious psychological problems. These problems affect not only the patients’ quality of life but also the beginning, development, and end of the disease. This paper reviewed the relationships between the patients’ personal factors, the disease itself, treatment factors, and other socio-psychological factors and psychological conditions so as to provide new ideas for the psychological intervention on breast cancer patients, comprehensive clinical diagnosis and treatment, and prevention and cure.
文摘Teaching content of Higher Mathematics is systematic and rigor with a high degree of abstraction. Because different students are on the different basis and different disciplines have various requirements, mathematics is generally difficult for students. In order to improve the quality of teaching mathematics, we should make use of individualized teaching and teaching by different levels in order to achieve the best teaching results.
文摘The process of dispersal is determined by the interaction of individual （intrinsic） traits and environmental （extrinsic） factors. Although many studies address and quantify dispersal, few evaluate both intrinsic and extrinsic factors jointly. We test the relative importance of intrinsic traits （exploration tendency and size） and extrinsic factors （population density and habitat quality） on dispersal of a medium-sized western United States minnow, southern leatherside chub Lepidomeda aliciae. A generalized linear model with a binomial response was used to determine the probability of individuals dispersing one year after tagging. Medium-sized individuals that were more prone to explore novel environments were 10.7 times more likely to be recaptured outside of their original capture area after a year （dispersal） compared to non-explorer individuals of the same size class. Differences be- tween explorer classifications within the small and large size classes were negligible. Open habitat within 50 m upstream also in- creased the probability of dispersal relative to controls. Relative location within the study reach, and population density were not significantly related to dispersal probabilities of individuals. Our results indicate that understanding of personality may illuminate patterns of dispersal within and among populations
基金supported by the National Natural Science Foundation of China under Grant No.61272041
文摘In this paper, based on spline approximation, the authors propose a unified variable selection approach for single-index model via adaptive L1 penalty. The calculation methods of the proposed estimators are given on the basis of the known lars algorithm. Under some regular conditions, the authors demonstrate the asymptotic properties of the proposed estimators and the oracle properties of adaptive LASSO(aL ASSO) variable selection. Simulations are used to investigate the performances of the proposed estimator and illustrate that it is effective for simultaneous variable selection as well as estimation of the single-index models.
