All Questions
8 questions
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low sample size experimental design, t-test vs one way ANOVA
I'm designing a biological experiment wherein the sample size is very limited, as each sample is very hard to get. Moreover, I need to have 4 independent groups, each receiving a different treatment.
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-1
votes
1
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45
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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 ...
0
votes
1
answer
399
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Is the statistical power of the Between-subjects effects in a Mixed ANOVA higher or the same compared to an independent samples t-test?
We have data on a physiological variable of interest (Metabolic Cost of Walking) from 2 groups of subjects (10 young adults and 10 old adults). We measured each one of them twice, once in the morning ...
3
votes
1
answer
57
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Which statistical test is appropriate if we can not measure normality
Say I have two devices that purifies milk, device A and device B. I assume Device B is better and it produces milk that is 5% better than A. If I want to test this assumption, I take 8 sample from the ...
8
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1
answer
431
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Is ANOVA always more powerful than a two-sample t-test when the data can be blocked?
I am trying to compare the efficacy of two devices. Three different operators tested each device for a parameter of interest (the same 3 operators for each device) and yielded two data sets for each ...
3
votes
1
answer
3k
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Calculating power function for ANOVA
There are several functions in R to calculate the power of a test, for example, the pwr-functions of the pwr package.
My question is how we get this function for ...
13
votes
4
answers
5k
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Power of a Mann Whitney test compared to a t test
So a Mann Whitney U test is supposedly about 95% as powerful as a t-test when t-test assumptions of normality and homogeneous variance are satisfied. I also know that a Mann Whitney U test is more ...
9
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2
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22k
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Power of the t-test under unequal sample sizes
I heard that the power of a t-test used with unequal samples is limited by the size of the smaller sample. Can I take this to mean that the power of a t-test with unequal sample sizes is equal to the ...