effect size

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    Power analysis and chi-squared control group sizes.

    hello, Quite new to stats, I've asked one question on here before and received a lot of really helpful information. If I can be helped again I'd be really grateful. at my job, the senior management, want to have the smallest control group possible, in order to expose the maximum amount of...
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    Determining Effect size for Quade Test

    Hello everyone, I did a Quade Test as a non-parametric alternative of the one-factorial repeated measures ANOVA, as my data are not normally distributed. My experimental design includes one factor having 3 levels (t1, t2, t3). All 28 subjects are confronted with all levels (t1, t2, t3) making...
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    effect size and significance

    Does anyone knows about the relationship between the effect size and the significance? I was given following question and no clue how to answer it: You hear that a study (randomized, controlled trial with two groups) found a small sized effect of a drug (n = 72) against placebo (n = 72) of d =...
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    Obtaining the individual, relative variance contributions of fixed and radnom effects of an LMM in R

    Hello, I am running a LMM (using the lmer4 package) with the following structure: lmer(Response~F1+F2+F3+(1|R1)+(1|R1:T2)+(1|R2)) For my research question I would like to quantify how much of the overall variance is explained by each indvidual fixed and each random effect. In other words I would...
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    Shapiro wilk effect size?

    Hi, Like any other test, using only the Shapiro-Wilk p-value is sometimes useless., especially with a large sample size ... I did some searches and didn't find any suggested way to calculate the SW effect size. (and interpretation) Usually, the direction is to run the SW test (or other) and...
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    Cohen's d interpretation

    The book says: 0.2 - small 0.5 - medium 0.8 - large I know that Cohen's interpretation is only a rule of thumb, so I'm not sure if there is a "one" answer. but what is the interpretation when d is between the values? Is d=0.3 small? or medium? Option 1 Range interpretation 0-0.2...
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    Sample size, effect size and power.

    Hi all, I have a question I haven't been able to answer. I hope you can help me :). I use G power to estimate sample size. In my case, the estimated sample size for my desired effect size = 0.25 and power = 0,95, is 400. But the estimated sample size for an effect size = 0.5 and power = 0,95...
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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...