Enregistrement multipisteL'enregistrement multipiste est une méthode d'enregistrement sonore qui permet l'enregistrement et le réenregistrement de plusieurs sources sonores, simultanément ou successivement. Ce procédé permet notamment d'enregistrer plusieurs musiciens (ou groupes de musiciens) séparément, puis un chanteur, et de corriger ou d'améliorer, grâce à de nouvelles prises, l'interprétation des uns ou des autres, sans avoir à reprendre l'ensemble. En audiovisuel, les pistes servent au dialogue, aux bruits d'ambiance, à la musique.
Loi log-normaleEn théorie des probabilités et statistique, une variable aléatoire X est dite suivre une loi log-normale de paramètres et si la variable suit une loi normale d'espérance et de variance . Cette loi est parfois appelée loi de Galton. Elle est habituellement notée dans le cas d'une seule variable ou dans un contexte multidimensionnel. Une variable peut être modélisée par une loi log-normale si elle est le résultat de la multiplication d'un grand nombre de petits facteurs indépendants.
Relationships among probability distributionsIn probability theory and statistics, there are several relationships among probability distributions. These relations can be categorized in the following groups: One distribution is a special case of another with a broader parameter space Transforms (function of a random variable); Combinations (function of several variables); Approximation (limit) relationships; Compound relationships (useful for Bayesian inference); Duality; Conjugate priors. A binomial distribution with parameters n = 1 and p is a Bernoulli distribution with parameter p.
Likelihoodist statisticsLikelihoodist statistics or likelihoodism is an approach to statistics that exclusively or primarily uses the likelihood function. Likelihoodist statistics is a more minor school than the main approaches of Bayesian statistics and frequentist statistics, but has some adherents and applications. The central idea of likelihoodism is the likelihood principle: data are interpreted as evidence, and the strength of the evidence is measured by the likelihood function.
Relative likelihoodIn statistics, when selecting a statistical model for given data, the relative likelihood compares the relative plausibilities of different candidate models or of different values of a parameter of a single model. Assume that we are given some data x for which we have a statistical model with parameter θ. Suppose that the maximum likelihood estimate for θ is . Relative plausibilities of other θ values may be found by comparing the likelihoods of those other values with the likelihood of .
One- and two-tailed testsIn statistical significance testing, a one-tailed test and a two-tailed test are alternative ways of computing the statistical significance of a parameter inferred from a data set, in terms of a test statistic. A two-tailed test is appropriate if the estimated value is greater or less than a certain range of values, for example, whether a test taker may score above or below a specific range of scores. This method is used for null hypothesis testing and if the estimated value exists in the critical areas, the alternative hypothesis is accepted over the null hypothesis.
Foundations of statisticsStatistics is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of data, and is used to solve practical problems and draw conclusions. When analyzing data, the approaches used can lead to different conclusions on the same data. For example, weather forecasts often vary among different forecasting agencies that use different forecasting algorithms and techniques. Conclusions drawn from statistical analysis often involve uncertainty as they represent the probability of an event occurring.
Bayes factorThe Bayes factor is a ratio of two competing statistical models represented by their evidence, and is used to quantify the support for one model over the other. The models in questions can have a common set of parameters, such as a null hypothesis and an alternative, but this is not necessary; for instance, it could also be a non-linear model compared to its linear approximation. The Bayes factor can be thought of as a Bayesian analog to the likelihood-ratio test, although it uses the (integrated) marginal likelihood rather than the maximized likelihood.
Écoute (surveillance)L’écoute est la surveillance par un tiers de conversations téléphoniques conventionnelles ou de communications réalisées via Internet, souvent par des moyens dissimulés. Les dispositions légales permettent à la justice d’autoriser l’écoute sous ses différentes formes par les autorités ou agences de renseignement pour des motifs reconnus comme autorisés. Parallèlement à ces formes de surveillance légale, peuvent se produire des écoutes illégales, résultant des agissements clandestins et non autorisés de personnes « privées » voire « publiques ».
Post hoc analysisIn a scientific study, post hoc analysis (from Latin post hoc, "after this") consists of statistical analyses that were specified after the data were seen. They are usually used to uncover specific differences between three or more group means when an analysis of variance (ANOVA) test is significant. This typically creates a multiple testing problem because each potential analysis is effectively a statistical test. Multiple testing procedures are sometimes used to compensate, but that is often difficult or impossible to do precisely.
