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2.6 Test based on medians

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 2: Tests of homogeneity of disp...

Levene’s test (for univariate data) can be made more robust (i.e. less affected by outliers) by u...

Updated 10 months ago by Abby Miller

2.4 Generalisation to dissimilarities

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 2: Tests of homogeneity of disp...

Of course, in many applications that we will encounter (especially in the case of community data)...

Updated 10 months ago by Abby Miller

2.2 Rationale

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 2: Tests of homogeneity of disp...

There are various reasons why one might wish to perform an explicit test of the null hypothesis o...

Updated 10 months ago by Abby Miller

1.38 Environmental impacts

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

Some further comments are appropriate here regarding experimental designs to detect environmental...

Updated 10 months ago by Abby Miller

1.37 Asymmetrical designs (Mediterranean molluscs)

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

Although a previous section has been devoted to the analysis of unbalanced designs, there are som...

Updated 10 months ago by Abby Miller

1.36 Linear combinations of mean squares (NZ fish assemblages)

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

Several aspects of the above analysis demonstrate its affinity with unbalanced designs. Note that...

Updated 10 months ago by Abby Miller

1.35 Designs with covariates (Holdfast invertebrates, revisited)

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

A topic that is related (perhaps surprisingly) to the topic of unbalanced designs is the analysis...

Updated 10 months ago by Abby Miller

1.16 Additivity

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

Central to an understanding of what an interaction means for linear models25 is the idea of addit...

Updated 10 months ago by Abby Miller

1.34 Types of sums of squares (Birds from Borneo)

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

When the design is unbalanced, there will be a number of different ways to do the partitioning, w...

Updated 10 months ago by Abby Miller

1.33 Unbalanced designs

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

Virtually all of the examples thus far have involved the analysis of what are known as balanced e...

Updated 10 months ago by Abby Miller

1.32 Repeated measures (Victorian avifauna, revisited)

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

While randomised blocks, latin squares and split-plot designs lack spatial replication, a special...

Updated 10 months ago by Abby Miller

1.30 Designs that lack replication (Plankton net study)

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

A topic related to the issue of pooling is the issue of designs that lack replication. Familiar e...

Updated 10 months ago by Abby Miller

1.29 Pooling or excluding terms

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

For a given design file, PERMANOVA, by default, will do a partitioning according to all terms tha...

Updated 10 months ago by Abby Miller

1.28 Estimating components of variation

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

The EMS’s also yield another important insight: they provide a direct method to get unbiased esti...

Updated 10 months ago by Abby Miller

1.27 Nested design (Holdfast invertebrates)

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

We have seen how a crossed design is identifiable by virtue of every level of one factor being pr...

Updated 10 months ago by Abby Miller

1.26 Testing the design

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

Given the fact that so many important aspects of the results (pseudo-F ratios, P-values, power, t...

Updated 10 months ago by Abby Miller

1.25 Inference space and power

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

It is worthwhile pausing to consider how the above tests correspond to meaningful hypotheses for ...

Updated 10 months ago by Abby Miller

1.23 Constructing $F$ from EMS

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

The determination of the EMS’s gives a direct indication of how the pseudo-F ratio should be cons...

Updated 10 months ago by Abby Miller

1.22 Expected mean squares (EMS)

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

An important consequence of the choice made for each factor as to whether it be fixed or random i...

Updated 10 months ago by Abby Miller

1.20 Fixed vs random factors (Tasmanian meiofauna)

PERMANOVA+ for PRIMER: Guide to Softwar... Chapter 1: Permutational ANOVA and MANO...

All of the factors considered so far have been fixed, but factors can be either fixed or random. ...

Updated 10 months ago by Abby Miller