Study On Information Niche Assessment System

With the development of information society and the updated of information technology, people suffer imbalance of the information ecosystem, such as information pollution, information redundancy, information violation. To construct a healthy information ecosystem, the ecological theory is applied to the field of information science. But the studies have largely ignored the dynamic of information ecosystem and the evolution mechanism, which can fundamentally solve the problems.Information niche is a basic unit of the information ecosystem, which develops with information niche change. Therefore, the study on information is beneficial to the study on information ecosystem and the analysis on imbalance. This is the purposes of studying information niche assessment system.At first, this paper reviews the research status quo and results at home and abroad, subsequently, introduces definition and elements of information niche. "Width" and "narrow" are the static characters; "generalization" and "Specialization" are the dynamic characters of information niche breadth. Information niche overlap has three forms in macro-field:coincidence, inclusion and overlap; It can be discussed from different dimensions and degrees in micro-field. Thereafter, relationship between information niche overlap and competition is analyzed. Information niche overlap is necessary condition to competition, but not sufficient. Information niche separation also includes three forms:departure, neighbor and overlap. Overlap whether causes competition depends on Competition point. This paper discusses the three ways of information niche change:expansion, compression and transfer, and also analyzes the reason, result and influence of change. Then, making use of principle of competitive exclusion, this paper provides the processes of Information niche change which the development of information ecosystem based on. On the basis, information niche assessment system is provided; this is the innovation of this paper. At last, this paper explained information niches of journals by analyzing the columns of journals, and that makes the theory advanced concrete.