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4.4 Simple linear regression (Clyde macrofauna)
In our first example of DISTLM, we will examine the relationship between the Shannon diversity (H...
4.3 Partitioning
Consider an (N × p) matrix of response variables Y, where N = the number of samples and p = the n...
4.2 Rationale
Just as PERMANOVA does a partitioning of variation in a data cloud described by a resemblance mat...
3.1 General description
Key references Method: , PCO is a routine for performing principal coordinates analysis () ...
2.1 General description
Key reference Method: PERMDISP is a routine for testing the homogeneity of multivariate dis...
1.1 General description
Key references Method: , Permutation techniques: , PERMANOVA is a routine for testing the...
3.9 PCO versus MDS
We recommend that, for routine ordination to visualise multivariate data on the basis of a chosen...
3.8 Distances among centroids (Okura macrofauna)
In chapter 1, the difficulty in calculating centroids for non-Euclidean resemblance measures was ...
3.7 PCO versus PCA (Clyde environmental data)
Principal components analysis (PCA) is described in detail in chapter 4 of . As stated earlier, P...
3.6 Vector overlays
A new feature of the PERMANOVA+ add-on package is the ability to add vector overlays onto graphic...
3.5 Negative eigenvalues
The sharp-sighted will have noticed a conundrum in the output given for the Victorian avifauna sh...
3.4 Example: Victorian avifauna
As an example, consider the data on Victorian avifauna at the level of individual surveys, in the...
2.12 Dispersion in crossed designs (Cryptic fish)
When two factors are crossed with one another, there may be several possible hypotheses concernin...
2.11 Dispersion in nested designs (Okura macrofauna)
In many situations, the experimental design is not as simple as a one-way analysis among groups. ...
2.10 Small sample sizes
There is one necessary restriction on the use of PERMDISP, which is that the number of replicate ...
2.9 Dispersion as beta diversity (Norwegian macrofauna)
When used on species composition (presence/absence) data in conjunction with certain resemblance ...
2.8 Choice of measure
An extremely important point is that the test of dispersion is going to be critically affected by...
2.7 Ecological example (Tikus Island corals)
An ecological example of the test for homogeneity is provided by considering a study by on coral...
2.6 Test based on medians
Levene’s test (for univariate data) can be made more robust (i.e. less affected by outliers) by u...
2.5 $P$-values by permutation
The other hurdle that must be cleared is to recognise that, in line with the philosophy of all of...