# Dictionary

Our dictionary contains descriptions and explanations to some words, terms and acronyms. For more exact statistical and mathematical formulas and definitions, please see Literature for Self Training.

**Analysis of variance**

A statistical technique to separate and estimate different causes of variation.

**ANOVA**

See Analysis of Variance.

**BSPC**

Batch Statistical Process Control.

**Chemometrics**

The application of mathematical and statistical methods to chemical data.

**Collinearity**

A high level of correlation between variables.

**Correlation**

Also correlation coefficient, the strength of the relationship between variables.

**Cross-validation**

A procedure of calculations to simulate the predictive power of a model, in order to determine its significance.

**D-optimal design**

A computer-generated design for non-standard conditions or when the experimental domains is distorted. The D in D-optimal stands for determinant.

**Design of Experiments**

A strategy for setting up a set of experiments in which all variables are varied in a systematic manner, for the purpose of determining the correlation between variables and to predict results.

**DOE**

See Design of Experiments.

**Interaction**

Also interaction coefficient, the strength of the relation between an independent variable and dependent variables, as a function of another indepdenent variable.

**Metabonomics**

The study of excreted metabolites of a species or an individual organism, involving measurements of the response to an influence.

**MLR**

Multiple Linear Regression.

**MODDE**

See MODDE in the product menu.

**Model**

The mathematical description of the behaviour of a system.

**MSPC**

Multivariate Statistical Process Control.

**Multivariate Data Analysis**

Regression analysis by projection methods such as PCA and PLS.

**MVDA**

See Multivariate Data Analysis.

**NIPALS**

See Nonlinear Iterative Partial Least Squares.

**Nonlinear Iterative Partial Least Squares**

Algorithm for calculating principal components.

**O-PLS**

Also Orthogonal PLS, a modification of PLS in which systematic variation in independent factors is divided into two parts; either related or non-related to the dependent responses.

**OLS**

Ordinary Least Squares, equivalent to MLR.

**Omics**

The study of a group or system of biomolecules.

**Partial Least Squares Projections to Latent Structures**

See Projections to Latent Structures.

**PAT**

See Process Analytical Technology.

**PCA**

See Principal Component Analysis

**PCR**

See Principal Component Regression.

**PLS**

See Projections to Latent Structures.

**PLS-DA**

Also PLS Discriminant Analysis, a PLS analysis involving a dummy variable for classification.

**Prediction**

A statement (usually quantitative) about what will happen under specific conditions, as a logical consequence of scientific theories.

**Principal Component Analysis**

A transformation where the data set receives a new coordinate system, in which new axes follow the direction of greatest variance in the data set.

**Principal Component Regression**

A regression technique that combines principal component calculations with MLR.

**Process Analytical Technology**

Systems for analysis and control of manufacturing processes based on timely measurements, during processing, of critical quality parameters and performance attributes of raw and in-process materials and processes to assure acceptable end product quality at the completion of the process.

**Projections to Latent Structures**

A regression technique for modelling the relationship between projections of dependent factors and independent responses.

**QSAR**

See Quantitative Structure-Activity Relationship.

**Quantitative Structure-Activity Relationship**

Estimation of the strength of a mathematical relation between chemical structure and pharmacological activity for a series of compounds.

**Rectangular Experimental Designs for Multi-Unit Platforms**

A set of designs, for experiments in 96-well plates using multi-pipettes.

**REDMUP**

See Rectangular Experimental Design for Multi-Unit Platforms.

**Regression**

The fitting of a curve to data points, expresses the mathematical relationship between variables.

**SBOL**

See SIMCA-Batch-On-Line in the product menu.

**Semiconductor**

**SIMCA**

Soft Independent Modeling of Class Analogy. See also the SIMCA software family in the product menu.

**Validity**

Term stemming from logical argument, stating that an argument is valid if, for every model, all premises in the model are true, then the conclusion in the model is true.

**Variability**

The variation between samples in the same condition, without systematic error.

**Variance**

Measurement of variability, equal to the square of standard deviation.