effect size

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    Effect sizes - Friedman's test

    Hello, I have a question regarding which measure of effect size to use. For Friedman's test, do I report the effect size when the result of the test is insignificant? For example, Field (2014) only reports the effect size of the post-hoc tests, but not the effect size for Friedman's test. If I...
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    Conflicting definitions: What is “effect size” regarding customer churn?

    One research paper says an example of "effect size" is the difference in the average age of churners vs. non-churners (41 vs 45). Another research paper says "effect size" is the difference in the area under the ROC curve (AUC was used to measure the validity of a model used to predict churn)...
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    Comparing differences between groups in different samples - which statistical test to chose?

    Hello everybody I am doing some research in sleep medicine where I compare the test results of different sleep and vigilance tests. Within these different vigilance test results, the data is sorted in different patient groups. Since my data is non-normally distributed, I performed a...
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    GPower f (V) effect size interpretation

    I am having difficulty understanding how to interpret effect size f(V) on GPower for a priori sample size calculation for ANOVA repeated-measures, within-between interaction. I am conducting an a priori power analysis to calculate sample size for ANOVA repeated measures, within-between...
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    Shapiro wilk effect size

    Hi, Do you know how to calculate the effect size for Shapiro Wilk test? When using Shapiro Wilk test on a large sample, most likely it will reject H0 even for normally distributed population, since large sample will identify the minor effect as significant. Thanks :)
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    Effect Size - Cohen's D calculation

    I had a question about how to calculate Cohen's D a particular situation for my meta-analysis. I am a first year grad student, so my familiarity with statistics is somewhat limited! The study design - participants are assigned to one of two groups (parallel design), but not a true RCT because...
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    Effect Size WRS2 package : Robust anova

    pplying the one way robust Anova of the WRS2 package for a specific dataset I get the following results: > t1way(totspcam ~ bono_recibido, data = spend_red) Call: t1way(formula = totspcam ~ bono_recibido, data = spend_red) Test statistic: 49.4939 Degrees of Freedom 1: 2 Degrees of...
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    Cohen d and Z scores

    Hi everyone, I should start by saying that I posted the same question that I will expose here on the psychological research forum. However, as I did not receive any answer, I wonder whether I misplaced my post. I apologize if this kind of repetition contravenes any of the rules of Talk...
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    Average effect size between factors and within an experimental condition

    Dear all, I am interested in an average effect size between heart rate and anxiety. Anxiety is separated in 2 factors (F1 and F2), and I would like to combine the correlations of those factors into one correlation. In addition, I also have the correlations between heart rate and anxiety...
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    How to calculate effect size f-squared in PLS-SEM using R programming

    Dear R experts, I am conducting a research using PLS-SEM approach using plspm package. However, I have no idea how to calculate effect size f-squared using R script in this case. Can anyone share some knowledge or any technical paper regarding this issue? I knew smart-pls software can...
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    comparing test results obtained on the basis of different sample sizes

    I have variables a1 and a2 with 57 observations each, and variables b1 and b2 with 29 observations each. I compare a1 with a2 by means of a paired-samples t-test, this gives p<0.001. Next, I compare b1 with b2 by means of a paired-samples t-test, this gives p>0.05 (actually p>0.10). I compared...
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    Sensitivity analysis said I wouldn't find an effect less than .8 but I did!

    Hello! I ran a sensitivity analysis on G*power and it told me that for my independent samples t test (10 people per group, alpha = .05, power =.8) I wouldn't find an effect size smaller than d = 1.32. I then ran the t test and got a significant result with an d = 1.15 How is this possible?
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    How can I intepret the effect sizes of Cramer's V when DF is high (like > 20)?

    Dear All, I am doing Pearson Chi Square analyses in SPSS. Besides looking at the Chi Square Sig. value I also want to look at Cramer's V to analyze the effect sizes. My dataset has 12 million observations na I found a value of 0.12 for the Cramer's V. Standards for interpreting Cramer’s seem to...
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    Sample size calculation for a one way anova (three conditions)??

    Hi there, I am designing a study that compares three conditions (differences in glass shape) on one main DV (drinking rate) (as well as some secondary DVs). I want an adequate sample size to be powerful enough to test the primary hypothesis, that there will be a difference between the three...
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    Calculating and Reporting Effect Size for Fisher's Exact Test?

    Hi everyone, I am writing a paper for publication. This is my first time doing a survey study, and also my first time working with categorical data (I, like many people unfortunately, have learned statistics bit by bit, as I have needed it in my research). The journal I am submitting to...
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    Post-Hoc Power Analysis (G*Power) for simple linear regression

    Hey everyone! I conducted a simple linear regression with non-significant results. Now I would like to analyze the power of this calculation using G*Power. I chose the option "F-tests - Linear multiple regression, fixedmodel, R(2) deviation from zero and entered 1 as my numer of predictors...
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    Confidence interval for Cohen's H

    hi everyone, I would like to create a Forest plot for a number of studies that looked at proportions. I calculated effect sizes using Cohen's H, but now I need to know the confidence intervals for those effect sizes. Does one of you know how to calculate those? Thanks in advance!
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    Effect Sizes

    This may seem like a ridiculous question, but it's bugging me and no text book or paper I've read has answered it. I am looking into research on effect sizes and their use in research. I see a lot of mention of Cohen's D and F2 and the "small", "medium" and "large" effect sizes. Can someone...
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    Using Pre-Post data in a meta-analysis

    Hello, I am trying to figure out the best way to calculate an effect size for a single-group design when I do not know the pair-wise correlation or standard deviation for the difference scores. I have received mixed messages as to whether or not I can use the formula for independent measures...
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    Repeated Measures Design & Effect Sizes, Normality

    My question is about calculating effect sizes for a repeated measures design with a small sample size. I want to calculate Cohen's d.av (as recommended by Lakens, 2013 and others) instead of d.z (which you can compute using just your t-value and N), since the latter tends to overestimate your...