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Chemometrics
Chemometrics is the science of extracting information from chemical systems by data-driven means. Chemometrics is inherently interdisciplinary, using methods frequently employed in core data-analytic disciplines such as multivariate statistics, applied mathematics, and computer science, in order to address problems in chemistry, biochemistry, medicine, biology and chemical engineering. In this way, it mirrors other interdisciplinary fields, such as psychometrics and econometrics. Background Chemometrics is applied to solve both descriptive and predictive problems in experimental natural sciences, especially in chemistry. In descriptive applications, properties of chemical systems are modeled with the intent of learning the underlying relationships and structure of the system (i.e., model understanding and identification). In predictive applications, properties of chemical systems are modeled with the intent of predicting new properties or behavior of interest. In both cases, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tormod Næs
Tormod Næs (born February 11, 1954) is a Norwegian statistician working in chemometrics and sensometrics. He studies multivariate statistical analysis, spectroscopy, food science, and sensory science. His impact on chemometrics is exemplified by the over 8,000 citations to his most well-known book, ''Multivariate Calibration'' (with Harald Martens), and the awards in chemometrics that he has received. Education Tormod Næs obtained both his master's degree (1978) and PhD (1984) in statistics from University of Oslo. Career For most of his career Næs has worked at Nofima (Norwegian Food Research institute) at Ås, achieving the title of Senior Scientist. He has been a professor at the University of Oslo, the University of Copenhagen, and Stellenbosch University. Næs has had four long research and guest professor periods abroad; at University of Washington (Seattle), University of Delaware, University of Genova and University of Firenze. Næs was member of The Board ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Partial Least Squares Regression
Partial least squares (PLS) regression is a statistical method that bears some relation to principal components regression and is a reduced rank regression; instead of finding hyperplanes of maximum variance between the response and independent variables, it finds a linear regression model by projecting the predicted variables and the observable variables to a new space of maximum covariance (see below). Because both the ''X'' and ''Y'' data are projected to new spaces, the PLS family of methods are known as bilinear factor models. Partial least squares discriminant analysis (PLS-DA) is a variant used when the ''Y'' is categorical. PLS is used to find the fundamental relations between two matrices (''X'' and ''Y''), i.e. a latent variable approach to modeling the covariance structures in these two spaces. A PLS model will try to find the multidimensional direction in the ''X'' space that explains the maximum multidimensional variance direction in the ''Y'' space. PLS regression ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemometrics And Intelligent Laboratory Systems
''Chemometrics and Intelligent Laboratory Systems'' is a peer-reviewed scientific journal sponsored by the Chemometrics Society and published since 1986 by Elsevier. The current editor-in-chief is R. Tauler (Barcelona, Spain). Abstracting and indexing The journal is abstracted and indexed in Analytical Abstracts, Cambridge Scientific Abstracts, Chemical Abstracts, Current Contents, Current Index to Statistics, EMBASE, Inspec, PubMed, Science Citation Index, and Scopus. According to the ''Journal Citation Reports'', the journal's 2020 impact factor is 3.491. In 2016 the journal's ranking was 15th out of 58 journals in the category "Automation & Control Systems", 29th out of 74 in the category "Chemistry, Analytical", 26th out of 123 in the category "Computer Science, Artificial Intelligence", 9th out of 56 in the category "Instruments & Instrumentation", 12th out of 99 in the category "Mathematics, Interdisciplinary Applications" and 8th out of 122 journals in the category "Stati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantitative Structure–activity Relationship
Quantitative structure–activity relationship models (QSAR models) are regression or classification models used in the chemical and biological sciences and engineering. Like other regression models, QSAR regression models relate a set of "predictor" variables (X) to the potency of the response variable (Y), while classification QSAR models relate the predictor variables to a categorical value of the response variable. In QSAR modeling, the predictors consist of physico-chemical properties or theoretical molecular descriptors of chemicals; the QSAR response-variable could be a biological activity of the chemicals. QSAR models first summarize a supposed relationship between chemical structures and biological activity in a data-set of chemicals. Second, QSAR models predict the activities of new chemicals. Related terms include ''quantitative structure–property relationships'' (''QSPR'') when a chemical property is modeled as the response variable. "Different properties or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Chemometrics
The ''Journal of Chemometrics'' is a monthly peer-reviewed scientific journal published since 1987 by John Wiley & Sons. It publishes original scientific papers, reviews, and short communications on fundamental and applied aspects of chemometrics. The current editor-in-chief is Age K. Smilde (University of Amsterdam). Abstracting and indexing ''Journal of Chemometrics'' is abstracted and indexed in: * Chemical Abstracts Service * Scopus * Web of Science According to the ''Journal Citation Reports'', the journal has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact factor values are considered more prestigious or important within their field. The Impact Factor of a journa ... of 2.467, ranking it 27th out of 64 journals in the category "Instruments & Instrumentation", 35th out of 63 journals in the category "Automation & Control Systems", 30th out of 125 journals in the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Svante Wold
Svante Bjarne Wold (March 14, 1941 – January 4, 2022) was a Norwegian-born chemist and applied statistician who developed the field of "chemometrics", coining the word in 1971. He was the son of the statistician Hermann Wold. Wold was born in Stockholm, the son of statistician Hermann and his wife Anna-Lisa Arrhenius, daughter of the physicist Svante Arrhenius. After military training, he joined the University of Uppsala, and then Umeå University Umeå University (; Ume Sami language, Ume Sami: ) is a public university, public research university located in Umeå, in the mid-northern region of Sweden. The university was founded in 1965 and is the fifth oldest within Sweden's present bord ... where he received a doctorate in chemistry. He joined the department of organic chemistry, later becoming a professor. In 1971, he coined the term ''kemometri'' which was translated into English as "chemometrics" and founded the International Chemometrics Society along with Bruce Kowal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolomics
Metabolomics is the scientific study of chemical processes involving metabolites, the small molecule substrates, intermediates, and products of cell metabolism. Specifically, metabolomics is the "systematic study of the unique chemical fingerprints that specific cellular processes leave behind", the study of their small-molecule metabolite profiles. The metabolome represents the complete set of metabolites in a biological cell, tissue, organ, or organism, which are the end products of cellular processes. Messenger RNA (mRNA), gene expression data, and proteomics, proteomic analyses reveal the set of gene products being produced in the cell, data that represents one aspect of cellular function. Conversely, metabolic profiling can give an instantaneous snapshot of the physiology of that cell, and thus, metabolomics provides a direct "functional readout of the physiological state" of an organism. There are indeed quantifiable correlations between the metabolome and the other cellular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Principal Components Analysis
Principal component analysis (PCA) is a Linear map, linear dimensionality reduction technique with applications in exploratory data analysis, visualization and Data Preprocessing, data preprocessing. The data is linear map, linearly transformed onto a new coordinate system such that the directions (principal components) capturing the largest variation in the data can be easily identified. The principal components of a collection of points in a real coordinate space are a sequence of p unit vectors, where the i-th vector is the direction of a line that best fits the data while being orthogonal to the first i-1 vectors. Here, a best-fitting line is defined as one that minimizes the average squared perpendicular distance, perpendicular Distance from a point to a line, distance from the points to the line. These directions (i.e., principal components) constitute an orthonormal basis in which different individual dimensions of the data are Linear correlation, linearly uncorrelated. Ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabonomics
Metabolomics is the scientific study of chemical processes involving metabolites, the small molecule substrates, intermediates, and products of cell metabolism. Specifically, metabolomics is the "systematic study of the unique chemical fingerprints that specific cellular processes leave behind", the study of their small-molecule metabolite profiles. The metabolome represents the complete set of metabolites in a biological cell, tissue, organ, or organism, which are the end products of cellular processes. Messenger RNA (mRNA), gene expression data, and proteomic analyses reveal the set of gene products being produced in the cell, data that represents one aspect of cellular function. Conversely, metabolic profiling can give an instantaneous snapshot of the physiology of that cell, and thus, metabolomics provides a direct "functional readout of the physiological state" of an organism. There are indeed quantifiable correlations between the metabolome and the other cellular ensembles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Econometrics
Econometrics is an application of statistical methods to economic data in order to give empirical content to economic relationships. M. Hashem Pesaran (1987). "Econometrics", '' The New Palgrave: A Dictionary of Economics'', v. 2, p. 8 p. 8–22 Reprinted in J. Eatwell ''et al.'', eds. (1990). ''Econometrics: The New Palgrave''p. 1 p. 1–34Abstract ( 2008 revision by J. Geweke, J. Horowitz, and H. P. Pesaran). More precisely, it is "the quantitative analysis of actual economic phenomena based on the concurrent development of theory and observation, related by appropriate methods of inference." An introductory economics textbook describes econometrics as allowing economists "to sift through mountains of data to extract simple relationships." Jan Tinbergen is one of the two founding fathers of econometrics. The other, Ragnar Frisch, also coined the term in the sense in which it is used today. A basic tool for econometrics is the multiple linear regression model. ''Econome ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biochemistry
Biochemistry, or biological chemistry, is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology, and metabolism. Over the last decades of the 20th century, biochemistry has become successful at explaining living processes through these three disciplines. Almost all List of life sciences, areas of the life sciences are being uncovered and developed through biochemical methodology and research.#Voet, Voet (2005), p. 3. Biochemistry focuses on understanding the chemical basis that allows biomolecule, biological molecules to give rise to the processes that occur within living Cell (biology), cells and between cells,#Karp, Karp (2009), p. 2. in turn relating greatly to the understanding of tissue (biology), tissues and organ (anatomy), organs as well as organism structure and function.#Miller, Miller (2012). p. 62. Biochemistry is closely ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proteomics
Proteomics is the large-scale study of proteins. Proteins are vital macromolecules of all living organisms, with many functions such as the formation of structural fibers of muscle tissue, enzymatic digestion of food, or synthesis and replication of DNA. In addition, other kinds of proteins include antibodies that protect an organism from infection, and hormones that send important signals throughout the body. The proteome is the entire set of proteins produced or modified by an organism or system. Proteomics enables the identification of ever-increasing numbers of proteins. This varies with time and distinct requirements, or stresses, that a cell or organism undergoes. Proteomics is an interdisciplinary domain that has benefited greatly from the genetic information of various genome projects, including the Human Genome Project. It covers the exploration of proteomes from the overall level of protein composition, structure, and activity, and is an important component of function ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
