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9.2 Periodic and cyclical models
Natural cycles in biology and ecology Important situations where the treatment of multiple covari...
9.1 Why group covariables together?
There are situations where it may be useful or important to include one or more quantitative co-v...
7.3 Not a dichotomy: a progression from fixed to random
What is meant by a 'finite' factor? Suppose, for any factor, there are a total of $A$ levels in t...
7.2 Dichotomy: fixed vs random factors
Consider the classical one-way linear ANOVA model, as described in section 6.2 above. Specificall...
7.1 Overview - Finite factors
ANOVA is one of the most widely used statistical techniques, providing a partitioning of the meas...
6.7 Heterogeneity in more complex designs
Handling heterogeneity with multiple factors The most important question to answer when you are d...
6.5 Solution to the multivariate BFP
Overview described a general dissimilarity-based solution to the multivariate Behrens-Fisher pro...
6.4 Multivariate Behrens-Fisher problem
Overview In a multivariate context, there are many ways that groups of sampling units can differ ...
6.3 The Behrens-Fisher problem (BFP)
Overview The Behrens-Fisher problem (BFP) is one of the oldest puzzles in statistics (; ; ). The ...
6.2 ANOVA in a nutshell
The one-way ANOVA model In one-way univariate analysis of variance (ANOVA), interest lies in comp...
4.9 Test of Association
Overview PRIMER 8 offers several options to achieve a non-parametric bivariate test of associatio...
4.7 Kolmogorov-Smirnov test
Overview The Kolmogorov-Smirnov test is a non-parametric test for comparing two distributions of ...
4.5 Kruskal-Wallis test
Overview The Kruskal-Wallis test was described by and . Its purpose is to compare two or more in...
4.3 Mann-Whitney U test
Overview The Mann-Whitney U test was described by and . Here, interest lies in comparing two gro...
3.1 Plots of empirical densities
Suppose we have measured a given variable in each of several groups. To visualise the distributio...
1.1 Expansion from P7 to P8
Summary statistics provide essential information to help you get to know your variables, their fu...
New Tools & Utilities in P8
New default colour palette - The new colour palette for PRIMER graphics ensures distinctive col...
1.2 Definitions of statistics
Given a set of values $\{ y_1, y_2, ..., y_n \}$ for any individual variable $Y$, the following s...
6.1 Overview - Allow heterogeneity
An important assumption of classical analysis of variance (ANOVA) is that the errors come from a ...
6.5 ANOSIM for two-way layouts
Three types of field and laboratory designs are considered here: a) the 2-way nested case can ari...