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.

learn more… | top users | synonyms (1)

2
votes
1answer
23 views

Why does APA suggest to report the F statistic with an ANOVA result?

I probably view it too pragmatic but to me, the F statistic is merely a result of a calculation that is used to (magically) determine the value that I'm really interested in: the p. APA, though, wants ...
0
votes
0answers
13 views

3-way ANOVA to 2-way ANOVA

I have an experimental design with 3 factors of 2 levels each, which are temperature (a1 & a2), pH(b1 & b2) and food (c1 & c2), so I first ran a 3-way anova. Since in 2x2x2 experimental ...
2
votes
1answer
40 views

Why bother looking at an omnibus ANOVA when I have a priori hypotheses about group differences?

I am examining three independent groups that were measured on a continuous outcome variable. I have a priori belief that the result should be Group 1 < Group 2 < Group 3. I've been told to do an ...
0
votes
1answer
18 views

Tukey's Test or LSD Fisher

I'm trying to solve the above exercise, but my question begins with which test should I choose: Tukey test or Fisher's LSD? I read several things and still can not tell the difference between the ...
1
vote
1answer
10 views

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 ...
1
vote
0answers
14 views

Dunnett's test help

Suppose that 30 percent cotton content is a control.Use Dunnett's test with $\alpha=0.05$ to compare all the other means with control. I'm using Montgomery book for study, then sorry if the ...
0
votes
1answer
13 views

Is SSB formula in ANOVA to find variance between groups valid for non-normal data?

I have two groups of non -normally distributed data (count data), and would like to find the variance between the groups. Am I able to use the SSB formula for this? The paper I have got the data from ...
2
votes
0answers
6 views

Violation of independence to be in multiple groups?

Ideally, I'd like to run an ANOVA across a variable regarding group membership on a continuous outcome variable. The problem is that each individual can be in multiple groups, which I believe violates ...
0
votes
0answers
57 views

Statistics Test Question - Help needed! [closed]

I am really terrible at statistics and basically don't even know where to begin on answering these. Any help would be appreciated. I've googled but there is some much info that it confuses me and I ...
0
votes
0answers
11 views

How to calculate the effect size after Welch ANOVA?

I used oneway.test() because Levene's test indicated heterogenity of variance. Unfortunately, I don't know how to calculate the effect size now. Does anybody have ...
0
votes
0answers
13 views

Decomposing the effect of x on y

I have an independent variable x, and a dependent variable y which is the sum of two variables, ...
1
vote
1answer
27 views

Downsides of having a model with too many independent variables (factors)?

It is often tempting in experimental design to make distinctions of all sorts in the manipulated variables, and thus to end up with a lot of factors in one's model (e.g. a 3x2x2x2x2 ANOVA). The same ...
1
vote
0answers
12 views

Test like ANOVA but allowing for multiple group membership

I have data where each individual tested has a score on a single common outcome variable, but may belong to multiple groups (in this case, sports teams - some only play football, others play soccer ...
0
votes
0answers
11 views

Statistical test for unordered repeated measures under same conditions

I am unable to find the correct statistical test for the following scenario. We have a recording session with 4 subjects. For each subject, we make 8 recordings in 2 different speaking styles, let ...
4
votes
0answers
92 views

Cheat Sheet ANOVA Alphabet Soup & Regression Equivalents

Can I get help completing this tentative (in progress) attempt at getting my bearings on ANOVA's and REGRESSION equivalents? I have been trying to reconcile the concepts, nomenclature and syntax of ...
1
vote
1answer
33 views

Can I use ANOVA & regression with likert data?

I am carrying out a research project investigating cheetah reintroduction as a conservation tool. One component of the study is to determine the tourism demand for cheetahs (essentially, do people ...
0
votes
1answer
12 views

How to analyse extremely low sample pre/post test data?

So the study involves assessments, then an intervention, and then the same assessments. There are two groups, 2 in one group, 1 in the other. Data is not binary but consists of scores on the ...
0
votes
0answers
7 views

Determining partial eta squared from an anova table without SS error

I was given the following information and asked to calculate partial eta squared: ...
0
votes
0answers
19 views

compare groups taking into account confounding factors

I have data from human participants in a study and I am using MATLAB to analyse it. The participants are divided in 4 groups according to their disease severity. The demographic characteristics of the ...
0
votes
0answers
13 views

A robust two-way repeated-measures anova in R?

Does anyone know whether it is possible to conduct a non-parametric/robust variant of a two-way repeated-measures anova in R? I can only find a variant of the one-way repeated-measures anova ...
1
vote
1answer
27 views

Multivariate Hypothesis Testing - How do you choose best combination of factors without explicitly testing every combination (2^n)?

Let's say I have 10 variables that I want to vary (each can be 0/1) on a page in order to determine what leads to the best conversion. How can I choose the best combination of factors without having ...
1
vote
0answers
19 views

to keep or not to keep… block effect when not significant?

The question is in the title. I could not find an answer to this common question after searching on google nor on the StackExchange website, excepted this but the provided answer is not definite ...
0
votes
1answer
19 views

Fisher's LSD test

When we calculate Fisher's LSD test, why do we use Mean Square of Error which is the variance of all groups (pooled variance), as a variance of each individual group mean? In the denominator it's: ...
0
votes
0answers
16 views

comparison of N groups of independent individuals curves: summary-variables or nonlinear mixed effect model?

I want to assess wether there is a significant difference among two groups, based on a sample of independent individual curves in each group. The logical next step is to try to understand what ...
0
votes
0answers
11 views

How important is normality assumption for a two-way repeated measures ANOVA?

I want to use two-way repeatead measures ANOVA. The dependent variable is CRP levels in three different time points in five different group of patients. Each group includes 40-42 patients, so that ...
1
vote
0answers
26 views

Frequentist statistics

Frequentist inference is the only form of statistics taught in my department, and I feel like it has a strong hold over many students here. But when I read data science blogs, I get the feeling that ...
4
votes
1answer
55 views

Is an ANOVA applicable for these data?

I have a data set from 7 groups, with 20 fish in each group. Measurement of a parameter is made on 25 cells from each fish (so each observation in the data-set is completely independent, right?). ...
2
votes
1answer
36 views

Is normality important for ANOVA when N>30?

I want to use repeatead measures ANOVA with sample size approximately n=40. Normality is violated according to S-W test. After log transformation although Q-Q plots seem better, the distribution is ...
0
votes
0answers
15 views

A/B, C/D test (fractional factorial design/anova?)

WE are conducting a test on a website and tracking number of form fills + the number of calls (by using a unique number of each variation). We basically have two base designs with two variation on ...
0
votes
0answers
12 views

Splitting a Two Way Anova for detecting effects

My question regards a specific case, which is the following. Hope someone can provide me with a clear, not too elaborated/statistical explanation if possible. Thanks in advance. Given 2 independent ...
0
votes
0answers
20 views

Two Way ANOVA not meeting the assumptions, moving to One Way Anova

I have the following ANOVA problem. Hope someone can help, thanks in advance. I have a sample of 120 respondents, split in 4 equal groups (4 groups originating from the combination of gender: ...
0
votes
1answer
24 views

Looking for something similar to a three way anova analysis for non-independent response samples

I have devised an experiment that consists of measuring how quickly a person can complete a set of tasks. I have three variables that I wish to investigate whether or not they affect the performance ...
1
vote
0answers
11 views

Using percentage values in ANOVA test?

I have a number of values expressed as an index (the proportion of heart muscle cells in s-phase compared to the total population of heart muscle cells, calculated as (number of S-phase cells / total ...
1
vote
0answers
23 views

$P$-value correction for ANOVA on repeated simulation

First of all, I would like to ask you if you know good literature that explains the theoretical underpinnings of multiple testing. Although I think I understand pretty well the basic principles, I ...
0
votes
0answers
18 views

Use of One Way ANOVA

In order to analyze the financial performance of Life Insurance Companies in India during a period of ten years, year wise certain financial ratios have been computed for all the selected companies. ...
0
votes
0answers
18 views

Asking input for this test scenario (Welch ANOVA instead of t-Test for two sample data)

I am asking for suggestions and comments on this test setup as I have not run tests with this type of data before. I am seeking to verify a (fishy) theory according to which economic downturns in the ...
1
vote
0answers
11 views

Reporting Results from a Mixed ANOVA

I have done a Mixed ANOVA on some data from a tennis serving experiment and am slightly confused on how to report the results. I am comparing the effect of self-talk (either instructional or ...
0
votes
0answers
18 views

Data failed Levene's test for ANOVA. Trying to Log10 transform the data but I'm getting -Inf results!

I'm new to R and trying to run some two-way ANOVAs to test treatment effects in an ecology study. I've just tested my data using the Levene function: ...
1
vote
0answers
18 views

Clarification on the comparison between regression lines

I have this dataframe: ...
0
votes
1answer
18 views

How does number of treatments affect ANOVA/Tukey-HSD results?

My data contains 3 treatments: A (n = 30), B (n = 15) and C (n = 5). I run an ANOVA test and reject the null hypothesis, so I perform a Tukey-HSD post-hoc test and find that there is a significant ...
2
votes
3answers
42 views

The F-test is a test for variance so why do we use F-test in ANOVA? [duplicate]

To test the mean vector we use ANOVA, and to test two variances we use the F-test, but my question is in ANOVA why we do use the F-test ?
0
votes
0answers
11 views

What type of ANOVA for my experiment?

So I've got four different groups of participants and they have to rate faces which have been manipulated in four different ways, A, B, C and D. I want to compare the mean ratings between ...
0
votes
0answers
12 views

Is reliability a requirement for ANOVA or regression analysis?

I would like to conduct ANOVAs and regression analyses with several DV's having a low reliability (cronbach's alpha < .40). This is probably due to the low number of items (2-3) in each scale. Is ...
0
votes
1answer
22 views

Manually calculating SS within for a one way ANOVA

Question Details: group 1 n= 30 M=78 SD=8 group 2 n=30 M=70 SD = 13 group 3 n=30 M=64 SD=13 I have to manually calculate a one way ANOVA summary table. I have been able to work out SS between ...
0
votes
0answers
18 views

(R) Calculate the “adjusted r^2” or its equivalent in a linear model that controls for a categorical variable

So I have a dataset that includes 3 columns: a categorical (discreet) variable (which is an input) and two outputs continuous variables. Both outputs are affected by that input. I want to see the ...
0
votes
0answers
17 views

ANOVA on a normally and a log-normally distributed variable: what to transform?

For an analysis of variance the residuals (but not the data?) have to be normally distributed. So, I have two variables, one is normally distributed, one is log-normally distributed, and their ...
1
vote
1answer
19 views

Repeated measures between treatment and control to assess difference and influence of time

I have been using a between-subjects repeated measures ANOVA for data of treatment effect where different subjects provide data that vary by time, i.e., each subject has a reading for ...
1
vote
0answers
20 views

Percent Change of Averages - Statistically significant testing and Standard Error

I have several different experimental conditions and for each condition I measure a value at Day 0, 4, 8, 12, and 16. (Control N=15, Condition 1 N=8, Condition 2 N=4...etc.) Given that the starting ...
0
votes
0answers
19 views

What type of ANOVA do I need to use?

At least I think it's ANOVA I could be totally wrong... I have two different groups of participants and four different types of faces. I want to compare the mean rating for each type of face ...