Questions tagged [split-plot]

An experimental design used in situations where one factor can be changed more easily than another one. It's also called "mixed design" because it involves between-subject (hard to change) and within-subject (aka repeated measures; easy to change) factors.

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12
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2answers
7k 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 ...
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5answers
11k 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) ...
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2answers
10k 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?
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1answer
8k 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 ...
8
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1answer
17k 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 ...
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2answers
906 views

Understanding the split plot

Can someone explain me the intuition behind the split plot? From what I understand, it is essentially restricted randomization. But I still do not quite understand it. Is there a resource or example ...
8
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1answer
5k 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 samples ...
7
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1answer
168 views

What is the specific issue with using count data for ANOVA tests

I'm running a study with a between-groups component and a within-groups component, with a predictor that is count data. I was planning on using split-plot ANOVA to analyze this, but after seeing lots ...
4
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1answer
1k views

Mixed-design with split-plot and mixed effect

From Wikipedia: a mixed-design analysis of variance model (also known as a split-plot ANOVA) is used to test for differences between two or more independent groups whilst subjecting participants to ...
4
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1answer
271 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 ...
4
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1answer
967 views

Mixed-design ANOVA or one-way ANOVA with delta values

I have an experiment with one independent variable with 4 levels (4 different treatments) and 1 dependent variable which was measured twice - before and after the treatment (repeated measures). I ...
4
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1answer
39 views

Cohen's d in split-plot experiments

There is some demand for effect-size measures in doing post hoc analyses, and I am trying to decide whether to provide for this or not in an R package of mine. If I do, I would concentrate on Cohen's $...
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0answers
1k 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: ...
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2answers
86 views

A curious clinical trial design - What is the type / name of this rare methodology?

There is this split-mouth randomized clinical trial, in which one side of the mouth receives a particular treatment, and the other side receives another treatment (usually used as the control ...
3
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2answers
654 views

Do Likelihood Ratio Tests "respect hierarchy" in linear mixed models?

The following example from the JSS paper on pkbrtest shows an LRT meant to test for the effect of the whole-plot treatment (harvest): ...
3
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1answer
485 views

Setting up a mixed model or a split-plot ANOVA for an experiment with male/female fishes in replicated tanks

I am designing an experiment with juvenile fishes. There are 12 replicated tanks. In each of the first 6 tanks there is a even mix of male and female fish (100 of each sex in each tank); 3 of these ...
3
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1answer
2k 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'. ...
3
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1answer
50 views

How to define a between variable is random effect in Anova in R? [closed]

I am using 'Anova' function in 'car' package to analyze plot - split experimental data. I have 1 between group, and 2 within group variables, so it is SPFp.qr analysis. The problem is, the between ...
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1answer
1k 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 temporal groups as blocks, and 2 ...
3
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0answers
569 views

Mixed model random-effect structure for repeated measures, split plot design in R (nlme or lme4)

I am seeking advice on structuring the random-effects component of a mixed model in R. The data that I am modeling come from an ecological experiment with a repeatedly-measured split-plot design. At ...
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0answers
827 views

Repeated measures on split plot design with blocking

This is the first time I'm posting a question here. I have regularly been using the questions and answers here as example solutions for my problems, and searching has always helped me figure things ...
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0answers
1k views

Split Plot Design? lmer analysis

I need advice regarding the analysis of a project that I am working at the moment. Here the picture of the experiment: We have an RCBD with four blocks. Within each block there are 5 plots. Each plot ...
3
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0answers
1k 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 ...
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0answers
832 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 ...
2
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1answer
3k views

Random Effects Design Matrix

I'm trying to move away from ANOVA/t-tests and get a better understanding of GLMs. I am doing my statistical analysis in R using function lm (only fixed effects) and lmer (+ random effects). I also ...
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2answers
133 views

Split plot design with psudo replicates

I am working on a project and need to analyze data that I know is an example of a split plot design but I am having trouble setting the model up correctly. Here's the situation: A bakery is testing ...
2
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1answer
9k 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 (...
2
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1answer
684 views

Split plot in time mixed-effect model in R

I am new to this website, to r, and to mixed effect models so apologise in advance if I exhibit a degree of ignorance. I am looking for help of how to fit a model for an experiment that I have done. ...
2
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1answer
150 views

Is it possible to compute some measure of effect size from four means from a split-plot (both within- and between-subjects) 2x2 design?

For a meta-analysis, we are interested in the comparison of two groups. From the articles, we can extract four means: two baseline measures on one of our dependent variables, and two measures ...
2
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2answers
1k views

Specifying a model with nested subsamples within split-plot design

I am trying to specify a model for split plot design that acknowledges nested sub-sampling. Split plot designs are a little bit tricky to analyze, and I am new to R, so I provide my dataset along with ...
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0answers
35 views

How do I decide which experimental design to use in order to properly analyse the collected data?

I'm struggling to understand which experimental design I should use. I used factorial design in most of my experiment but i recently read a document where it mention that the precision of some main ...
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0answers
150 views

Generate Grouped Data with Exact Correlations, Means, and SD

I want to generate data with the following constraints. There is one factor and two numeric variables. Note that the desired mean structure is broken down by factor, which is what makes this a ...
2
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0answers
855 views

Mixed model for three factors (split split plot design) with proportions as response

I am struggling with the analysis of a data set from an experiment done as follows: I have 5 blocks (that work as replicates) and each one of them was divided into two part (so split block), to each ...
2
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0answers
67 views

What is the difference between a 2x2x2 split plot ANOVA and a 2-way repeated measures ANOVA? [duplicate]

What is the difference between a 2x2x2 Split-Plot ANOVA and a 2-Way Repeated Measures ANOVA?
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0answers
859 views

Repeated measures anova and split plot design analysis

It is mentioned that repeated measure anova may be very similar to split-plot design: Is a "split plot" ANOVA with two factors the same as two-way ANOVA with repeated measures in one factor?...
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0answers
1k 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
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0answers
451 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 ...
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2answers
10k views

What can cause a "Error() model is singular error" in aov when fitting a repeated measures ANOVA?

I have the following data set: ...
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1answer
1k views

Is my design 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) I am ...
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1answer
914 views

Split Plot ANOVA in R

I have an experimental design in which I am comparing two or three types of soil (depending on how I group them) across two elevation transects. My overall goal is to compare different soil types, but ...
1
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1answer
981 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 ...
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1answer
19 views

Mixed Effect Model - Nested Block labelling

My data has 5 blocks . Within each block, the same 3 sub-blocks (1,2,3)are applied to each individual. I want to examine the the effects of the blocks and sub-...
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1answer
35 views

Change parameters block-wise in experiment design?

Is it possible to generate an experiment design which changes a parameter block-wise? To be more precise what I would like to do: Run an experiment with a certain parameter (humidity) fixed which is ...
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1answer
951 views

Split split plot ANOVA table: r = replicate or block?

I have seen various ANOVA tables for analysis of split split plot designs, and some have the first term ''r'' defined as the block while others have it as the replicate. This is confusing to me, as ...
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1answer
1k views

Split-plot analysis with four factors in SAS

I'm trying to correctly model a split-plot design with more than two factors (specifically, four) in SAS. I'm interested in an example from Design and Analysis of Experiments (Montgomery , 8th Ed.), ...
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0answers
33 views

Power, split plot designs, and mixed models

My teammate and I are trying to determine the best way to allocated limited resources (shade cloth and fencing) in an experiment. We are considering 2 factors: light availability (2 levels) and water ...
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0answers
33 views

No significance in the multivariate tests

Hope this question is not too stupid. I haven't taken the MANOVA course yet, but I need to figure out a problem right now. I am running a mix-model MANCOVA on SPSS. I have no significance in the ...
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0answers
27 views

Bayesian Split-Plot Design with heterogenous Variances / Kruschke / JAGS / ANOVA

I try to analyze a split-plot design and try to get my head around the code. My problem is that we were only able to gather a convenience sample of patients grouped into 11 different disorders at 2 ...
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0answers
100 views

How to code a two-way ANOVA with split-plot design using R?

I am analyzing a split-plot land-use experiment and I am stuck on the R code. We used four sites and on each site the following design: We conducted a full-factorial design with two factors (land-...
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0answers
50 views

Type of ANOVA to use: Split-Plot, Nested … or others? Water quality project

I was wondering if I could get some help in determining the correct ANOVA analysis to run on a water quality project in am working on. My dataset have the following variables: Habitat Type (fixed) (...