Document retrievalDocument retrieval is defined as the matching of some stated user query against a set of free-text records. These records could be any type of mainly unstructured text, such as newspaper articles, real estate records or paragraphs in a manual. User queries can range from multi-sentence full descriptions of an information need to a few words. Document retrieval is sometimes referred to as, or as a branch of, text retrieval. Text retrieval is a branch of information retrieval where the information is stored primarily in the form of text.
The Structure of Scientific RevolutionsThe Structure of Scientific Revolutions is a book about the history of science by philosopher Thomas S. Kuhn. Its publication was a landmark event in the history, philosophy, and sociology of science. Kuhn challenged the then prevailing view of progress in science in which scientific progress was viewed as "development-by-accumulation" of accepted facts and theories. Kuhn argued for an episodic model in which periods of conceptual continuity where there is cumulative progress, which Kuhn referred to as periods of "normal science", were interrupted by periods of revolutionary science.
DSL modemA digital subscriber line (DSL) modem is a device used to connect a computer or router to a telephone line which provides the digital subscriber line (DSL) service for connection to the Internet, which is often called DSL broadband. The modem connects to a single computer or router, through an Ethernet port, USB port, or is installed in a computer PCI slot. The more common DSL router is a standalone device that combines the function of a DSL modem and a router, and can connect multiple computers through multiple Ethernet ports or an integral wireless access point.
Community organizationCommunity organization or Community Based Organization refers to organization aimed at making desired improvements to a community's social health, well-being, and overall functioning. Community organization occurs in geographically, psychosocially, culturally, spiritually, and digitally bounded communities. Community organization includes community work, community projects, community development, community empowerment, community building, and community mobilization.
StemmingIn linguistic morphology and information retrieval, stemming is the process of reducing inflected (or sometimes derived) words to their word stem, base or root form—generally a written word form. The stem need not be identical to the morphological root of the word; it is usually sufficient that related words map to the same stem, even if this stem is not in itself a valid root. Algorithms for stemming have been studied in computer science since the 1960s.
Tf–idfIn information retrieval, tf–idf (also TF*IDF, TFIDF, TF–IDF, or Tf–idf), short for term frequency–inverse document frequency, is a numerical statistic that is intended to reflect how important a word is to a document in a collection or corpus. It is often used as a weighting factor in searches of information retrieval, text mining, and user modeling. The tf–idf value increases proportionally to the number of times a word appears in the document and is offset by the number of documents in the corpus that contain the word, which helps to adjust for the fact that some words appear more frequently in general.
Community psychologyCommunity psychology is concerned with the community as the unit of study. This contrasts with most psychology which focuses on the individual. Community psychology also studies the community as a context for the individuals within it, and the relationships of the individual to communities and society. Community psychologists seek to understand the functioning of the community, including the quality of life of persons within groups, organizations and institutions, communities, and society.
