# Tags

A tag is a keyword or label that categorizes your question with other, similar questions. Using the right tags makes it easier for others to find and answer your question.

 Type to find tags:
 matrix× 180 a rectangular array of numbers, symbols, or expressions arranged in rows and columns. The individual items in a matrix are called its elements or entries. terminology× 179 Indicates questions asking about the use and meaning of specific technical words/concepts in statistics. sample× 178 a subset of a population. Statistics, in general, is concerned with using samples to make inference about the parameters governing a larger (possibly infinite) population. books× 175 a generic tag for requests of any kind of resources: books, textbooks, manuals, papers, presentations, video lectures, scripts, etc. multicollinearity× 168 Multicollinearity means predictor variables are correlated with each other, making it harder to determine the role each of the correlated variables is playing. Mathematically, it means the standard er… random-generation× 168 The act of generating a sequence of numbers or symbols randomly, or (more often) pseudo-randomly; i.e., with lack of any predictability or pattern. power-analysis× 168 An inquiry into the quality of a statistical test by calculating the power - the probability of rejecting the null hypothesis given that it is false - under certain circumstances. Power analysis is of… model× 166 a formalization of relationships between variables in the form of mathematical equations. The model is statistical as the variables are not deterministically but stochastically … k-means× 163 a family of cluster analysis methods in which you specify the number of clusters you expect. This is as opposed to hierarchical cluster analysis methods. meta-analysis× 162 Meta-analysis refers to methods focused on contrasting and combining results from different studies, in the hope of identifying patterns among study results, sources of disagreement among those result… assumptions× 160 Refers to the conditions under which a statistics procedure yields valid estimates and/or inference. E.g., many statistical techniques require the assumption that the data are randomly sampled in some… normality× 160 Refers to the normal distribution, the Gaussian continuous probability distribution. reliability× 158 said to have a high reliability if it produces similar results under consistent conditions. DO NOT confuse reliability with validity (see tag wiki). aic× 157 AIC stands for the Akaike Information Criterion, which is one technique used to select the best model from a class of models using a penalized likelihood. A smaller AIC implies a better model. binary-data× 156 In broader sense - synonym of "dichotomous data": any data that can take on only one of two values. In narrower sense - dichotomous data coded as 1 or 0; furthermore, sometimes "1" is supposed to mean… sem× 154 a multivariate technique popular in social sciences. It is based on formulating a set of linear relations between variables, some of which may be latent, and estimating… dimensionality-reduction× 153 Dimensionality reduction refers to techniques for reducing many variables into a smaller number while keeping as much information as possible. One prominent method is [tag pca] excel× 151 a commercial spreadsheet program created by Microsoft. summary-statistics× 151 A brief numerical description of a set of data. ancova× 150 Analysis of Covariance. effect-size× 146 "a measure of the strength of a phenomenon or a sample-based estimate of that quantity" [Wikipedia]. fitting× 145 power× 145 Is a property of a hypothesis testing method: the probability of rejecting the null hypothesis given that it is false, i.e. the probability of not making a type II error. The power of a test depends o… r-squared× 143 In linear regression, the coefficient of determination, usually symbolized by $R^2$, is the proportion of the total response variance explained by the regression model. count-data× 143 non-negative integers representing whole amounts. When such data are the dependent variable in a regression, Poisson or negative binomial regression may be appropriate methods. One comm… basic-concepts× 143 scales× 142 bias× 141 Bias, in a statistical framework, means that an estimate of a parameter has an expected value that is not equal to the actual parameter value. There is often a tradeoff between bias and variance - low… computational-statistics× 141 Refers to the interface of statistics and computing; the use of algorithms and software for statistical purposes. logit× 141 A name given to the log-odds function, which maps probabilities to the real line. curve-fitting× 140 prior× 139 In Bayesian statistics a prior distribution formalizes information or knowledge (often subjective), available before a sample is seen, in the form of a probability distribution. A distribution with la… roc× 136 Receiver Operating Characteristic, also known as ROC curve. robust× 134 Robustness in general refers to a statistic's insensitivity to deviations from its underlying assumptions (Huber and Ronchetti, 2009). large-data× 133 'Large data' refers to situations where the number of observations is so large that it necessitates changes in the way the the data analyst thinks about or conducts the analysis. group-differences× 133 Group differences broadly refer to statistics which quantify the differences between two or more subpopulations.