Central Location
Central Location: Central location is a synonym of central tendency . Browse Other Glossary Entries
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Complete Linkage Clustering
Complete Linkage Clustering: The complete linkage clustering (or the farthest neighbor method) is a method of calculating distance between clusters in hierarchical cluster analysis . The linkage function specifying the distance between two clusters is computed as the maximal object-to-object distance , where objects belong to the first cluster, and...
View Full DescriptionClassification Trees
Classification Trees: Classification trees are one of the CART techniques. The main distinction from regression trees (another CART technique) is that the dependent variable is categorical. One of the oldest methods for classification trees is CHAID . Browse Other Glossary Entries
View Full DescriptionChi-Square Test
Chi-Square Test: Chi-square test (or -test) is a statistical test for testing the null hypothesis that the distribution of a discrete random variable coincides with a given distribution. It is one of the most popular goodness-of-fit tests . For example, in a supermarket, relative frequencies of purchasing 4 brands of...
View Full DescriptionCHAID
CHAID: CHAID stands for Chi-squared Automatic Interaction Detector. It is a method for building classification trees and regression trees from a learning sample comprising already-classified objects. An essential feature is the use of the chi-square test for contingency tables to decide which variables are of maximal importance for classification. Another...
View Full DescriptionChi-Square Statistic
Chi-Square Statistic: The chi-square statistic (or -statistic) measures agreement between the observed and hypothetical frequencies. This statistic is computed from two entities: hypothetical probabilities of the values of a discrete random variable , and the observed frequencies of these values - the numbers of observations of each type. The chi-square...
View Full DescriptionCentral Tendency (Measures)
Central Tendency (Measures): Any measure of central tendency provides a typical value of a set of values . Normally, it is a value around which values are grouped. The most widely used measures of central tendency are (arithmetic) mean , median , trimmed mean , mode . Measures of central...
View Full DescriptionCensus Survey
Census Survey: In a census survey , all units from the population of interest are analyzed. A related concept is the sample survey, in which only a subset of the population is taken. The main advantage of the census survey (as compared to the sample survey ) is that the...
View Full DescriptionComplete Block Design
Complete Block Design: In complete block design, every treatment is allocated to every block. In other words, every combination of treatments and conditions (blocks) is tested. For example, an agricultural experiment is aimed at finding the effect of 3 fertilizers (A,B,C) for 5 types of soil (1...5). There are 15...
View Full DescriptionAcceptance Region
Acceptance Region: In hypothesis testing, the test procedure partitions all the possible sample outcomes into two subsets (on the basis of whether the observed value of the test statistic is smaller than a threshold value or not). The subset that is considered to be consistent with the null hypothesis is...
View Full DescriptionAcceptance Sampling
Acceptance Sampling: Acceptance sampling is the use of sampling methods to determine whether a shipment of products or components is of sufficient quality to be accepted. Browse Other Glossary Entries
View Full DescriptionAcceptance Sampling Plans
Acceptance Sampling Plans: For a shipment or production lot, an acceptance sampling plan defines a sampling procedure and gives decision rules for accepting or rejecting the shipment or lot, based on the sampling results. Browse Other Glossary Entries
View Full DescriptionAdditive Error
Statistical Glossary Additive Error: Additive error is the error that is added to the true value and does not depend on the true value itself. In other words, the result of the measurement is considered as a sum of the true value and the additive error: where is the result...
View Full DescriptionAdditive effect
Statistical Glossary Additive effect: An additive effect refers to the role of a variable in an estimated model. A variable that has an additive effect can merely be added to the other terms in a model to determine its effect on the independent variable. Contrast with interaction effect. Browse Other...
View Full DescriptionAgglomerative Methods (of Cluster Analysis)
Agglomerative Methods (of Cluster Analysis): In agglomerative methods of hierarchical cluster analysis , the clusters obtained at the previous step are fused into larger clusters. Agglomerative methods start with N clusters comprising a single object, then on each step two clusters from the previous step are fused into a bigger...
View Full DescriptionAggregate Mean
Aggregate Mean: In ANOVA and some other techniques used for analysis of several samples, the aggregate mean is the mean for all values in all samples combined, as opposed to the mean values of the individual samples. The term "aggregate mean" is also used as a synonym of the weighted...
View Full DescriptionAlternate-Form Reliability
Alternate-Form Reliability: The alternate-form reliability of a survey instrument, like a psychological test, helps to overcome the "practice effect", which is typical of the test-retest reliability . The idea is to change the wording of the survey questions in a functionally equivalent form, or simply to change the order of...
View Full DescriptionArithmetic Mean
Arithmetic Mean: The arithmetic mean is a synonym of the mean . The word "arithmetic" is used to discern this statistic from other statistics having "mean" in their names, like the geometric mean , the harmonic mean , the power mean , the quadratic mean Browse Other Glossary Entries
View Full DescriptionARIMA
ARIMA: ARIMA as an acronym for Autoregressive Integrated Moving Average Model (also known as Box-Jenkins model ). It is a class of models of random processes in discrete time or time series . ARIMA model is widely used in time series analysis . ARIMA model extends the autoregressive moving average...
View Full DescriptionAutoregression and Moving Average (ARMA) Models
Autoregression and Moving Average (ARMA) Models: The autoregression and moving average (ARMA) models are used in time series analysis to describe stationary time series . These models represent time series that are generated by passing white noise through a recursive and through a nonrecursive linear filter , consecutively . In...
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