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0
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0answers
36 views

Post hoc split plot design

I have an experiment in which I have four fenced large plots. I subdived every fenced plot into three smaller fences to have three grazing levels. Within every grazing level I planted 20 saplings ...
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0answers
19 views

Augmented split plot experimental design

I planned a field experiment with different genotypes according to an augmented design (check repeated entries plus unrepeated entries). Since I am testing a segregating population, each plot split ...
0
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0answers
27 views

Split plot ANOVA or t-test

I did a study in which I wanted to see if a teaching intervention would have an effect on student learning. I nonrandomly divided students into two groups, a control and experimental group, and gave ...
3
votes
1answer
133 views

Split plot with factorial design vs three way ANOVA

I have three site temperature types: cold, medium, and hot. This is a fixed effect - I am specifically am testing if temperature affects my response variable. I believe temperature type is my 'block'. ...
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2answers
615 views
0
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0answers
68 views

aov() error strata degrees of freedom

I have the following data frame: ...
0
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1answer
95 views

Tests of within subjects contrasts in R

I have run a split splot model in SPSS (via repeated measures function) and I would like to reproduce my results using R. To do so I used ezANOVA function from ez package to obtain sphericity tests ...
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0answers
15 views

Whole Plot Optimizations for Designed Experiments

I was looking into the DoE.wrapper collection of packages for R and I was interested in generating a split-plot design like I might in JMP. In JMP I can specify ...
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0answers
247 views

lme / lmer - split-plot with Non orthogonal subdesign

I have an agricultural field experiment (testing a plant protection agent): Split plot design with: ...
0
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0answers
23 views

Nested Design, Split-plot or ANOVA

I have general statistical question concerning the analysis of two-factorial experiments. I would like to compare several response variables (biovolume, richness etc.) of two experiments (homogeneous ...
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0answers
47 views

Experiment Design - Randomized Block or Completely Randomized

We have Five litters of rats, each containing four rats. The five litters were randomly selected from a population of litters. Investigators are interested in comparing the mercury content from fish ...
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0answers
54 views

Is this a split plot?

I have attempted to view the following experiment as a split plot design: 15 undergraduates serve as subjects for an experiment that compares two hypnosis methods. There are two phases to the ...
1
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0answers
28 views

Methods of dealing with non-independent data in ordinations

Forgive if this question is too broad, but i'm wondering if there is a way to deal with spatial pseudoreplication in ordinations? I have a split-plot treatment design, and am wanting to run ...
2
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0answers
364 views

Analyzing split-plot design in lme4 in R

I have the data from a split-plot design where A is my whole plot fixed factor with two levels and B is my subplot fixed factor with 2 levels and C is my random block factor. How do I analyse these ...
7
votes
1answer
1k views

Nested/SplitModel - RepeatedMeasures/MixedModel ANOVA: levels of nesting & scripting in R

My data set has the following variables: Treatment (4 types- fixed) Location (8 locations- fixed) Position in Location (3 positions per location- fixed) Samples are taken in each position (3 ...
1
vote
1answer
193 views

Nested or Split plot

I have a design with four factors Frame (positive negative neutral) Graphic ( graph no graph) Color (red grey) nested in graphic Position of color (nested in color, which is nested in graphic) ...
2
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0answers
492 views

Split-split-split plot cross-over design… is this even possible?

I'm doing statistical analysis on a psychology study I ran a short while ago, and I'm starting to think that I've designed myself into a corner. In the study, we measured participants' pointing ...
1
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0answers
465 views

Split plot design with repeated measures in package (nlme) - model errors

Forgive me if this answer is already somewhere on this site, but after extensive searching I have found nothing to help me. Here is a brief overview of the experiment: I have 18 tanks, each of which ...
2
votes
1answer
3k views

How to interpret an interaction effect in SPSS output for a repeated measures anova with between and within group factors?

I have conducted a repeated measures ANOVA, with 2 factors: One between factor (Ex_control: exercise intervention versus control) One within factor (...
1
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0answers
366 views

Building a mixed model for multi-location split plot over 2 years in SAS

For the last 3 weeks I have been reading books, papers and internet sources incl. cross validated but could not find something that would work in my case. I have data from a split-plot field trial. ...
3
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0answers
501 views

How to choose between nested or split-plot analysis of variance?

I am having serious problems understanding the type of design I have, I would appreciate any help you can give me to understand it: I have 324 data points, and four factors: ...
1
vote
0answers
279 views

Error bars calculation in a split-plot design

I have the following experimental design : Sampling is carried out on three random sites (Factor Site is coded : Site1, Site2, Site3). Within each site, sampling is carried out in a dry plot and in a ...
1
vote
0answers
431 views

How to determine the ANOVA table for split-plot with repeated measures experiment?

I have an experiment where observations are one of eight different treatment combinations and are then either one of two different heights. There are 4 blocks, with 8 plots for each block, and the two ...
7
votes
1answer
2k views

Split-split-plot design and lme

I’m working on a data set in order to evaluate the impact of drying on sediment microbial activities. The objective is to determine if the impact of drying varies among sediment types and/or depth ...
3
votes
2answers
3k views

Is a “split plot” ANOVA with two factors the same as two-way ANOVA with repeated measures in one factor?

Is a "split plot" ANOVA with two factors identical to two-way ANOVA with repeated measures in one factor? if not, what is the distinction?
5
votes
1answer
4k views

Split plot in R

I have a data set of $n$ benchmarks and $m$ subsamples in each benchmark. I run these benchmarks and their subsamples on $p$ subject machines. The 'individual' studied by the subsamples are the same ...
10
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2answers
4k views

Split-Plot ANOVA: model comparison tests in R

How can I test effects in a Split-Plot ANOVA using suitable model comparisons for use with the X and M arguments of ...
4
votes
1answer
221 views

How can I treat blocks in a split plot design?

In a field experiment involving crops, what is the difference in considering block as random or otherwise as fixed factor? As far as I understood, random means that conclusion can be extended to other ...
3
votes
1answer
803 views

Can I test the effect of Block in a split plot design in R?

I have been confused with the problem for a very long time, and hope that somebody here can help me out~ I have a experiment installed in split-plot design, with 3 temperal groups as blocks, and 2 ...
1
vote
1answer
803 views

Unbalanced repeated measure design for the given data?

I have 3 factors factor1 (treatment) with 2 levels (control, stress) factor2 (Variates) with 12 Levels (Var1, Var2,....Var12) factor3 (Time) with 12 levels (Week1, Week2,..., Week12) The treatment ...
5
votes
2answers
2k views

Omega squared for measure of effect in R?

The statistics book I am reading recommends omega squared to measure the effects of my experiments. I have already proven using a split plot design (mix of within-subjects and between-subjects design) ...