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1.5 Environmental data: summary stats
For environmental data, we might choose to calculate different sorts of summary statistics than t...
1.4 Split summary stats results by groups
To run summary statistics on your variables separately for multiple groups of data, just choose a...
1.3 Biotic data: summary stats
To show the utility of this tool, we will calculate some summary statistics from a study examinin...
14.1 Overview
There is a new tool in PRIMER 8 that permits the end-user to create a set of ordered groups, base...
13.1 Overview
PRIMER 8 offers a host of new options for standardising data (either samples or variables), via t...
12.6 Additional notes on implementing control charts
We offer here a few additional notes regarding the implementation of control charts in real appli...
12.5 Dissimilarity-based multivariate control chart
Essential steps Suppose we have an $(N \times p)$ data matrix, $\bm{Y}$, and we can capture the i...
12.3 Classical multivariate control chart
A suitable criterion for a control chart designed to detect shifts in the population mean vector ...
12.2 Classical univariate control chart
A classical univariate control chart arises in the context of process control for industrial and ...
12.1 Overview - Control charts
Rationale Suppose you have multivariate data (e.g., abundances of multiple species) sampled repea...
10.1 Ordinations for multi-factor designs
Rationale When considering the response of a whole set of variables (such as the abundances of sp...
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 ...