# 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.

for any *on-topic* question that (a) involves R either as a critical part of the question or expected answer, & (b) is not *just* about how to use R.
27131 questions
Techniques for analyzing the relationship between one (or more) "dependent" variables and "independent" variables.
26489 questions
Machine learning algorithms build a model of the training data. The term "machine learning" is vaguely defined; it includes what is also called statistical learning, reinforcement learning, unsupervis…
18349 questions
Time series are data observed over time (either in continuous time or at discrete time periods).
13120 questions
A probability provides a quantitative description of the likely occurrence of a particular event.
11188 questions
Hypothesis testing assesses whether data are inconsistent with a given hypothesis rather than being an effect of random fluctuations.
9440 questions
A distribution is a mathematical description of probabilities or frequencies.
8709 questions
A routine exercise designed to test one's knowledge; often from a textbook, course, or test used for a class or self-study. This community's policy is to "provide helpful hints" for such questions rat…
7682 questions
Artificial neural networks (ANNs) are a broad class of computational models loosely based on biological neural networks. They encompass feedforward NNs (including "deep" NNs), convolutional NNs, recu…
7404 questions
Bayesian inference is a method of statistical inference that relies on treating the model parameters as random variables and applying Bayes' theorem to deduce subjective probability statements about t…
7227 questions
Refers generally to statistical procedures that utilize the logistic function, most commonly various forms of logistic regression
7107 questions
Mathematical theory of statistics, concerned with formal definitions and general results.
6948 questions
Statistical classification is the problem of identifying the sub-population to which new observations belong, where the identity of the sub-population is unknown, on the basis of a training set of dat…
6405 questions
A measure of the degree of linear association among a pair of variables.
5786 questions
Statistical significance is a characteristic of a statistic viewed in light of a null hypothesis and a given significance level. It reflects whether the statistic belongs to the rejection region (is s…
5761 questions
The normal, or Gaussian, distribution has a density function that is a symmetrical bell-shaped curve. It is one of the most important distributions in statistics. Use the [normality] tag for asking ab…
5545 questions
Mixed (aka multilevel or hierarchical) models are linear models that include both fixed effects and random effects. They are used to model longitudinal or nested data.
5417 questions
Regression that includes two or more non-constant independent variables. Also known as multivariable regression.
4967 questions
ANOVA stands for ANalysis Of VAriance, a statistical model and set of procedures for comparing multiple group means. The independent variables in an ANOVA model are categorical, but an ANOVA table can…
4910 questions
Python is a programming language commonly used for machine learning. Use this tag for any *on-topic* question that (a) involves Python either as a critical part of the question or expected answer, &…
4288 questions
A confidence interval is an interval that covers an unknown parameter with $(1-\alpha)\%$ confidence. Confidence intervals are a frequentist concept. They are often confused with credible intervals wh…
4129 questions
A generalization of linear regression allowing for nonlinear relationships via a "link function" and for the variance of the response to depend on the predicted value. (Not to be confused with "genera…
4033 questions
The expected squared deviation of a random variable from its mean; or, the average squared deviation of data about their mean.
3853 questions
Cluster analysis is the task of partitioning data into subsets of objects according to their mutual "similarity," without using preexisting knowledge such as class labels. [Clustered-standard-errors a…
3799 questions
Prediction of the future events. It is a special case of [prediction], in the context of [time-series].
3577 questions
A test for comparing the means of two samples, or the mean of one sample (or even parameter estimates) with a specified value; also known as the "Student t-test" after the pseudonym of its inventor.
3310 questions
Categorical (also called nominal) data can take on a limited number of possible values called categories. Categorical values "label", they do not "measure". Please use [ordinal-data] tag for discrete …
3309 questions
Repeatedly withholding subsets of the data during model fitting in order to quantify the model performance on the withheld data subsets.
3230 questions
Principal component analysis (PCA) is a linear dimensionality reduction technique. It reduces a multivariate dataset to a smaller set of constructed variables preserving as much information (as much v…
3228 questions
too general; please provide a more specific tag. For questions about the properties of specific estimators, use [estimators] tag instead.
3071 questions
a method of estimating parameters of a statistical model by choosing the parameter value that optimizes the probability of observing the given sample.
3010 questions
lme4 and nlme are R packages used for fitting linear, generalized linear and nonlinear mixed effects models. For general questions about mixed models use [mixed-model] tag.
2943 questions
Creating samples from a well-specified population using a probabilistic method and/or producing random numbers from a specified distribution. As this tag is ambiguous, please consider [survey-sampling…
2937 questions
Constructing meaningful and useful graphical representations of data. (If your question is only about how to get particular software to produce a specific effect, then it is likely not on topic here.)
2859 questions
Predictive models are statistical models whose primary purpose is to predict other observations of a system optimally, as opposed to models whose purpose is to test a particular hypothesis or explain …
2817 questions
Refers to the AutoRegressive Integrated Moving Average model used in time series modeling both for data description and for forecasting. This model generalizes the ARMA model by including a term for d…
2712 questions