Questions tagged [fishers-lsd]
Fisher's LSD is a method to compare multiple group means following a significant ANOVA.
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Is correction for multiple comparisons necessary in this instance (single variable)?
Coming here from a more analytical chemistry background, but I figured I would run my current thoughts here before committing to anything after looking around for a bit. I'm used to always using ...
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What is the algorithm for grouping means in a multiple comparisons LSD test?
Starting from the means of 10 treatments where the Fisher LSD interval is 2.1, how do you "manually" determine the number of homogeneous groups (a, b, c, d ...) and which mean belongs to ...
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Why does weights argument in glm change the outcome of lsd?
I have dataframe df.
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Combining One-way ANOVA followed by Fishers LSD and unpaired ttests?
I am analysing data on levels of proteins in the brain, there are 4 groups, I did a one way anova followed by Fishers LSD. I also carried out individual unpaired ttests comparing each group to the ...
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How can I obtain degrees of freedom of LSD test that give Inf?
I am performing a LSD test after getting GLMM results. My goal is to know the differences between classes (in this case the difference between grinding methods, I assayed III methods). The GLMM output ...
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FIsher's LSD test is appropriate for restricted mean comparisons
Suppose that we perform two way ANOVA with interactions, with factors $A$ and $B$ with three level each $A_{1},A_{2},A_{3}$ and $B_{1},B_{2},B_{3}$.
We know that Fisher's LSD test is used for ...
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How to determine significant difference between treatments
What statistical method would you apply to determine if treatments are statistically different. For one treatment I have 26 samples all with 4 measurements. Those measurements are then averaged for ...
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Can Fisher's LSD fail to identify difference when the overall ANOVA test rejects?
I understand that Fisher's LSD test is used as a post hoc analysis if the ANOVA test rejects the null hypothesis All the means $X_1, X_2,.. X_n$ taken from various samples are equal.
Also, given ...
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Post Hoc test: Fisher LSD or pairwise two sample t.tests
A Fisher LSD test is basically a series of pairwise t-test except that the pooled variance is computed on all groups (and therefore does not vary from one comparison to another) while the normal t-...
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What are the drawbacks and benefits for the Bonferroni Adjustment, Fisher's LSD, and Tukey's HSD procedures?
When do you use which test and which test is best for isolating the differences in multiple comparisons?
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Biochemistry table interpretation help!
I have a table that uses the Fisher LSD and has significance "in each column". I'm having trouble interpreting it. Is the significance just for that individual column or can they compare to other ...
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lsmeans multiple comparisons and Fishers LSD
I am using the lsmeans package for "post hoc" multiple comparisons and I read here: ANOVA - Do we need a global test before post hoc tests? that in general post hoc ...
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Reject $H_0: \mu_1 = \mu_2 = \mu_3$ but not $H_0: \mu_1 = \mu_2, H_0: \mu_3 = \mu_2,$ or $H_0: \mu_1 = \mu_3$? [duplicate]
Is it possible to reject
$$H_0\!: \mu_1 = \mu_2 = \mu_3,$$
for example, with an F test in the context of an ANOVA table, but not reject any of the following:
\begin{align}
H_0\!: \mu_1 &= \mu_2 ...
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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 two ...
user72621
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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: ...
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Is Fisher's LSD as bad as they say it is?
When we perform experiments (on small sample sizes (usually the sample size per treatment group is about 7~8)) on two groups, we use a t-test to test for difference. However, when we perform an ANOVA (...
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