Questions tagged [repeated-measures]
Repeated measures data occur when more than one measurement is collected on the same unit (e.g. subject). Use this tag for RM-ANOVA together with [anova] tag.
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Does Greenhouse-Geisser correction influence the effect size estimation, the statistical significance treshold, or both of them?
I discussed recently with one of my colleagues about the Greenhouse-Geisser correction for non-sphericity. I told him first that this correction is very conservative and that it would be more ...
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Effect size measure for doubly-repeated measures design?
Update:
I haven't gotten any answers, so I am simplifying my question. Say I measure test scores of $100$ people in one of two conditions. Each test has $10$ items. On each item, each person can ...
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Simple trend analysis with unbalanced & short panel data
I have the following (unbalanced) panel data: yearly sustainability ratings (ESG) of ca. 2000 individual firms over a 11-year period. The average observations per firm only covers 5.3 periods. These ...
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Should I control for random effects of participant in an individual differences design?
I'm trying to analyse a survey study in which I'm interested in the way that individual differences between my participants influence how they respond to my stimuli. The stimuli are pieces of writing ...
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Mixed design terminology: "Within-subjects variables" and "random effects"
I have trouble understanding the following statement on Wikipedia about mixed design ANOVAs:
Thus, in a mixed-design ANOVA model, one factor (a fixed effects factor) is a between-subjects variable ...
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ROC curves for repeated measures
I am trying to model ROC curves for a longitudinal dataset where participants were measured between 1-13 times. Time is not of interest but the fact that the measurements are autocorrelated an issue. ...
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Is this longitudinal data too complicated for GLMM or GEE?
After writing this post, I've realized that I am running around in circles, chasing my tail. Any help approaching this problem would be greatly appreciated, as I think I just need to bounce ideas ...
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When using repeated-measures ANOVA in R, what does it mean to specify Error(subject) instead of Error(subject/(A*B))?
For a two-way repeated measures design, we can specify the model using aov in the following fashion:
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Confused about the correct model specification given the study design (fully-crossed factors with nested repeated measures)
THE ISSUE
Apologies in advance, being primarily a biologist and only tangentially a statistician I hesitate to ask this question for fear of overly complicating a simple situation. That said, I have ...
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Accounting for repeated measures by resampling data and averaging parameter estimates misses the mark, but why?
Let's say I am looking at how unicorn herd size changes with food quantity. Unicorn herd sizes were surveyed at seven localities over the course of twelve months. Food quantity was assessed monthly, ...
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Modeling binomial outcomes with repeated measures
I'm looking at patterns of a particular injury within individuals and how they vary by age and sex. For each of 1365 individuals I have four locations each of which may be positive for this injury.
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Syntax differences between aov and lmer for two-way repeated measures design
I'm working with the following data frame using R. It consists of measurements obtained from 7 subjects with two independent variables (IV1 and ...
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What is the origin of the Winer's compound symmetry test of the variance-covariance matrix?
In his famous book, Winer (Statistical principles in experimental design 1971; reedited Winer, Brown, Michels, 1991, p. 517) introduced a test of compound symmetry. The test expands on the likelihood ...
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Propensity matching and analysis of resultant data on a data set with repeated measures
We have extracted retrospective case-level data collected over several years. We are using the administration of rescue antiemetic in the postanesthesia care unit as a proxy for postoperative nausea ...
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Calculating Cohen's d for pre-post/treatment-control design where treatment-control is also a repeated/within factor
I'm conducting a meta-analysis of studies that used pre-post/treatment-control designs. Most of them are mixed designs (pre-post is repeated/within; treatment-control is independent/between) with a ...
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notation for the regression equation in a nested and repeated measures random effects model
I'm looking for help with regard to the notation for a regression equation in a repeated measures model with nested data, $\eqref{eq:2}$, and connecting the notation back to my model specification, <...
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Data observed with multiple but unpaired/unmatching observations
I have a dataset with repeated measures, in which for each unit $i$, we observe multiple observations (for the same variable) $y_{ij}$ and multiple $x_{ik}$, but we don't know which $y_{ij}$ ...
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Generalized eta squared
Partial eta-squared are very often used in psychological litterature. As underlined by some authors (e.g., Baguley, 2009; Bakeman, 2005; Olejnik & Algina, 2003), this standardized measure of ...
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Computing effect size (partial eta squared) from a RM-ANOVA's F value
I want to calculate the number of participants I need in order to get a power of 0.95, when replicating an effect. The effect size of this effect is not reported in the previous study, which is why I ...
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Is there a principled ANOVA-like approach when a "subject" factor forms a symmetric 2D matrix?
I have a dataset where the dependent variable is a similarity measure between any 2 data channels, lets call it S(i,j), with a few dozen simultaneously recorded channels (so there are quite a few ...
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Is it possible to calculate a log-odds ratio with repeated trials?
Background and Problem
This is a continuation of a question posted earlier (here) in which I describe a meta-analysis combining between- and within-subject designs using log-odds ratios (OR) as the ...
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Testing for differences between time series with many timepoints
I think the easiest way to describe my question is with plots.
I've run an experiment where I recorded data from animals' brains (EEG) at 6 depths. The animals are recorded at baseline for 25 minutes,...
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What is the ANOVA equivalent of a matched-pairs t-test? MANOVA?
I have n subjects. I perform an experiment on all the subjects and measure the outcome in two different ways. I want to evaluate the difference between these two types of measurements. I would use a ...
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Is repeated measures ANOVA right for this experimental design? Unsure
I have 2 to 5 subjects (different sea organisms) that will be exposed to several different treatments (varied doses of bacteria). Each group is done in triplicate due to the variability of the ...
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Analyzing the effects of different scholarships among university students
We have a data set that has data on university students, including their
socio-demographic characteristics (sex, first language, ethnicity,
residency etc.),
GPA and CGPA in each semester (note that ...
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Mixed between-within subjects ANOVA
I am wondering how interpret tables. I used a mixed ANOVA for analyzing:
My within-subjects factor is time (pretest, posttest, follow-up) my between-subjects factor consists of conditions (...
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How does GEE (Generalized Estimating Equation) treat different cluster size?
I have a population of 200,000+ patients and their hospital visit information. I'm trying to see if having a certain disease would have an effect on whether they will have readmission or not (this is ...
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Longitudinal data analysis where meaning and metric of response variable varies over time
Determining what factors predict change over time is a topic of investigation in many fields and there are a variety of readily implemented methods for analysing repeated measures in the same metric.
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Simulation for power analysis for higher order repeated measures ANOVA
I am attempting to find a way to perform a power analysis for a higher order repeated measures ANOVA where all factors are within-subjects (i.e., there are no between-subjects factors). I have looked ...
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Repeated measures approach or not?
The basic question here is whether the following situation would warrant a repeated measures approach with a mixed effects model or not.
Let's say I have a set of grocery stores in 5 different ...
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Statistical test to compare different treatments over time
In my experiment I have 4 treatments (the control plus the variables: A, B, C) and I am comparing the growth among them.
I have 4 replicates for each treatment. Thus 16 samples in total.
Every other ...
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Fitting a multilevel model to data from an experiment with between- and within-subjects factors
I have data from an experiment that I would like to analyse with a multilevel model. In the experiment, participants read 1 scenario about a person and they had to answer a couple of questions about ...
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Friedman test to report on occurrence of categories in multiple articles
To investigate reasons for certain behavior, we have defined three categories for these reasons, and have determined how often these were mentioned across 15 (very different) scientific articles. ...
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Interpretation of mixed model with repeated measures
I have performed the following experiment: Two genotype groups of two different ages were monitored in the presence of three drugs one after the other. So, each subject after a control period received ...
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Linear Discriminant Analysis: Using subject as classification
I have a problem where I need to identify from which subject a particular set of data points came. More specifically, my problem is that I need to demonstrate that my subjects (N=9) can be ...
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Should I run measurement invariance if confirmatory factor analysis is not affirmative?
I have a repeated measures design for a Likert scale with 10 items. This scale is assumed to be unidimensional and this is one of the research questions along with the scales measurement invariance (...
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Book on Repeated Measure Analysis
Can anyone recommend a good book or some other reading materials
on repeated measure analysis using mixed model.
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GLM experimental design issues for count data in landscape experiment
I am analyzing bird count data from surveys conducted each week (from Nov-April, when bird foraging most active near breeding cycle) for 6 years in 9 large experimental plots that are split amongst 3 ...
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Repeated measures interaction betwen SNP and treatment with R
This is my first question is this forum. I have the a problem that I want to solve with the lme function of the nlme package of <...
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Linear mixed effects vs. Repeated Measures
I have 46 replicate trees I sampled in a 2 year study.
My objective is: To estimate the proportion of variation among-trees w/in year, and proportion variation due to among year and tree interaction.
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Is repeated measures ANOVA appropriate for my experiment and is my sample size large enough?
I'm really confused. I never took statistics but am trying to read up as much as I can. I didn't think much about statistical analysis until after doing the experiment, unfortunately, but maybe ...
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Compare three groups with very small sample size
I have three treatments: control, treatment1, and treatment2. A total of four patients were examined after receiving each of these three treatments. The dependent variable is continuous. My dataset ...
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Is a linear mixed-effect model the correct approach?
I conducted a crossover study where 10 subjects performed tasks using two different methods (A and B) based on different conditions. 5 of the subjects started with method A and 5 subjects started with ...
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How to adress the -0.71 correlation artefact in the pre-post analysis of change from baseline in non-randomized trials?
Let me make some introduction first.
It's well known, that in randomized trials, in the pre-post trials, by the formal pharmaceutical regulatory guidelines, both raw post and change scores should be ...
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Implementation and interpretation of time-varying covariates/predictors and their interaction with time in linear mixed effects model
I have a longitudinal design, where we are interested in the relationship between clinical symptoms (continuous data) and brain data (also continuous) both measured over two timepoints. As we have a ...
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Equivalence of ANCOVA and repeated measures model
Consider an RCT with individuals i in 2 arms (group, with 0 = control and 1 = treatment) in which one metric outcome (score) is collected at baseline (pre) and after some treatment (post).
In an ...
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ANOVA/ANCOVA - how to analyse
In a basic research design where you want to test how some intervention (let's say our IV is 'drinking' with the categories
water;
sprite; and
rum)
affects some continuous measurement (let's say ...
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Generalized Linear Mixed Effects Logistic Regression with Repeated Measures
I have an experiment where subjects reported multiple results (binary) in two treatments. I have compared each subject separately to see if the treatment had an effect on a given subject, but would ...
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Using GLMM to explain vegetation change as a function of change in soil parameters
I have a dataset that consists of vegetation datasets (species/abundancy tables) and soil parameters (tested for ten parameters per soil core). Three different rounds of these data are recorded in ...
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Should this be a one-way repeated measures anova?
I'm a new phd researcher and I just completed my first set of experiments. Participants played the same game using three different control mechanisms. In the game they had to complete a series of ...
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