Questions tagged [anova]
ANOVA stands for ANalysis Of VAriance, a statistical model and set of procedures for comparing multiple group means. The independent variables in an ANOVA model are categorical, but an ANOVA table can be used to test continuous variables as well.
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Diagnostics for the analysis of variance model
I have problem with the diagnostic of the one way analysis of variance model (fitted in R).
I've checked all the assumptions of the analysis of variance
1) "For each level of the within-subjects ...
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How to calculate p value from ANOVA function for LMM results?
I have used ANOVA function so that I can get the overall p value of significant factors:
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ANOVA in R: How MSresiduals are estimated when using Error(interaction)?
I have checked the existing answers, but I found no answer to my question. It is about choosing the right ANOVA model in R and how the MSresiduals are estimated.
I have an experiment with two ...
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Which test do I use; need to compare tests with one another pre and post intervention
I am writing a thesis on the validity of balance training tests.
I need to compare the tests and see if they correlate with one another in testing balance in the elderly.
There's a control and ...
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Two way ANOVA or ANCOVA
I need to show that BMI of adults is neither age nor gender specific. Should I do ANCOVA or randomly make age groups and do two way ANOVA?
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Stata ANOVA Interaction term differences
The following two statements produce different results.
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repeated measures ANOVA - non-experimental data
For every year, for eight years, I have a set of projects (n=332). The number of projects that exist in each year varies (for example, some years there are 10 projects others there are 60). In each ...
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Question about Time 1/Time 2 analysis
I was hoping to get some input on the best way to test some data that I have collected (using SPSS).
In short, respondents make an evaluation at time 1, then complete a distractor task, and then ...
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Treating numeric as categorical variable in regression
I need a little bit of help and confirmation that I have the right idea.
I have some fake data of 8 tribes; within each tribe members work hard to gain food for their own tribe. No one can speak to ...
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one way and two ways anova
anova can be used to test the influence of a factor on an output.
One way anova is used if we are considering only one factor and two ways anova can be used if we are considering two factors.
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ANOVA with Repeated Measurements based on randomly assigned repetitions
first of all the basic idea of my experiment: changes/differences of reaction time (RT) after 3 different types of sport (a: no jogging=SP1; b: 10min of jogging=SP2 and c: 30min of jogging=SP3);
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Collapse dimension when comparing model coefficients
I have a dataset that includes 2 dimensions (A, B), each of which has the same two categories (1,2). I fit a model to the data in each of the 4 conditions and get 4 coefficients for a parameter of ...
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Data arrangement ANOVA
I am using Stata to perform an ANOVA analysis. I would like to ask for help on how to arrange data. This is a texture analysis and I have four data sets (four different time points)
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repeated measure ANOVA with non-consecutive repeats
I have a somewhat of a repeated measure setup but wanted to check if repeated measure 1-way anova can be applied here (assuming underlying assumptions of normality, sphericity etc are met).
Situation:...
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Constructing an appropriate aov command in R
I have some interlaboratory data where we have tested recovery weights of 3 different batches of product in three labs, with varying numbers of operators in each lab (see below).
I want to know ...
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Question about Tukey post-hoc ANOVA test results
I have used a Tukey post-hoc test after seeing that the ANOVA test indicated some significant differences between my groups (A,B,C,D). I am somewhat confused about the results.
Why, for example, is A ...
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anova, t-test, linear models: run on individual data points or per-person means?
The format of my studies is testing 10 individuals in 5 conditions 100 times per condition (this is a behavioral test) - resulting in around 5000 raw data points.
I am currently using 3 statistical ...
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Repeated measurement analysis advice in R lme and / or aov and a couple of more questions
I want to analyse the visual performance, operationalized via contrast threshold, depending on adaptation luminance and spectrum, gathered for 29 subjects. I'm currently kind of confused of how to do ...
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Degrees of freedom due to treatment
let $a$ be the number of treatments.
In Randomized Complete Block Design(RCBD), degrees of freedom due to treatment is $(a-1) $
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let $k$ be the number of treatments exactly in each block in a ...
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Analysis to use with categorical response and categorical predictor variables
I have data from a randomized survey experiment in which each respondent was assigned to one of 4 groups, one of which can be considered a "control" or "no treatment" group. The key question asked in ...
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Comparing pre-test post-test results t-test normal distribution
Is the best way to compare the intervention group (n=32) with the control group (n=32) to do a t-test? I've got pre-test and post-test results and did t-test of both the pre-scores (IG compared to CG) ...
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Calculating 95% confidence interval for Repeated Measurement ANOVA output
I'm conducting a repeated measurement ANOVA analysis below (both factors are within-subject factors):
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How do I transform my data when only some treatments are not normal
I've run a shapiro-wilks test on my data to determine its normality, however the results show that some of the treatments are not normal (P<0.05). Do I transform all of the data, or do I just ...
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Intro stats, one-way repeated measures ANOVA finding standard deviation from missing data?
I'm trying to do a one-way repeated measures ANOVA, but I'm missing some data in the question (I'm not looking for the answer, just a hint on what I'm missing here..). The data in question is:
Paint ...
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Repeated Measures ANOVA post hoc test (bayesian)
I am trying to understand the procedure of carrying out a Bayesian Repeated Measures ANOVA. In a conventional repeated measures ANOVA, I calculate the effect of a certain parameter (e.g., study ...
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Is there a concern for multiple comparisons when ranking instead of using significance?
Let's say I have many ANOVA tests on the same data using different factor variables each time. Then, I want to rank the F-statistics for all of those tests. Notice that I'm not interested in ...
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Is there a way to check for the good amount of replicates for let's say T test or just mere One-Way anova (a priori)?
I have already asked this in Reddit but I really cannot find the answer
I know you can check for amount of sample sizes in G power but not really for experiments.
I can't be using a minimum of 100 ...
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Fixed and Random Effects / Fixed and Random Factors
What is the difference between a fixed effect and a random effect?
Are fixed and random effects different from fixed and random factors?
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How do I derive the Sum of Squares sums for an arbitrary ANOVA?
I know it is possible to derive the Sums of Squares sums for a simple one-way CRD ANOVA. It is done by substituting the treatment factors into the total SS equation, then squaring, eliminating terms ...
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Reporting non-significant regression analysis?
As a result of attached regression analysis I found non-significant results and I was wondering how to interpret and report this. I am a self-learner and checked Google but unfortunately almost all of ...
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Understanding Pearson goodness of fit and deviation in R - using anova (test= Chisq)
I have run a Pearson goodness of fit and deviance to test the fit of the model but I don't quite understand how to interpret my output.
I used an anova to run it:
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How to validate Anova assumption of gaussian residuals in python
I think I have some fundamental misunderstandings when it comes to the assumptions behind ANOVA.
Lets suppose there is a function that maps y to x with the following equation, y=3x+2. Now suppose we ...
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correlation and ANOVA can they yield disparate results?
I am analysing 3 tests applied to the same sample of students. I correlated the results and then ran an ANOVA to check for statistical significance and a post-hoc test to see where the difference ...
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Statistical test to use to test mean equality given non-independence assumptions
In a survey conducted, 75 survey participants were asked to rate randomized keywords from groups 1-5. Every keyword belongs to a group and subjects were asked to rate each keyword. I would like to ...
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Confidence Intervals in ANOVA testing
I have read other posts before raising this question. I understood the mechanics behind Anova but I have not fully grasped its essence in logical terms. What I mean is that if I calculate the mean ...
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How can I check if three or more results are statistically identical?
I conducted several experiments (for the moment 3, but there will be more in the near future), where in each experiment I made several measurements. I know (from previous experience) that the result ...
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What statistic analysis should i use?
I need to analyze this data. Tried with anova and independent t-test but i have no results. with t-test says t cannot be computed because standard deviation of both groups is zero, in anova says that ...
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Which statistical test to use for my data
My question is whether a low calorie diet with prescribed exercise is more effective than a low calorie diet without prescribed exercise for weight loss
study design: randomised study of 2 parallel ...
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grouping of groups (ANOVA)
Background: One of my hypothesis' is that several (more than 2) groups (hereafter sub-groups) can be grouped, based on an interval-scaled variable, into two groups that, based on the same interval-...
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Comparing sets of independent sets with one another
This question is somewhat hard for me to articulate (I'm not extremely familiar with stats). My problem is this: I have a set of users, lets say User0-UserN. Each user has the potential to generate ...
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3 way mixed ANOVA & pairwise comparisons effect size
I have a 3 way mixed ANOVA, where I have 2 significant main effects, one significant two way interaction and a significant three way interaction.
I've been told to not describe the lower order ...
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Hierarchical linear regression analyses, but with logarithms?
I was ask to do a linear regression analyses of my variables. I have Reaction times. Can you recommend me a linear regression analysis (hierarchical?) and tell me whether I should transform my raw ...
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Interpreting interactions in 2 way ANOVA
I ran a 2 way anova with 2 categorical IVs, i.e. age(young/old) and condition(control/low alcohol/high alcohol/marijuana) and 1 continuous IV. Most critically, here are my p-values on my interaction ...
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ANOVA table help
I need to find values for the starred values. I have been trying for some time but cannot figure out how to find them. I was able to find the Degrees of freedom, F and Significance of F. I have no ...
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