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Questions tagged [fishers-lsd]

Fisher's LSD is a method to compare multiple group means following a significant ANOVA.

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How to find orthogonal projection of a d-dimensional point, d>2 on Fisher's discriminant?

We know that the number of Fisher's discriminant to find for classifying data in given dimension d into output classes K, is min(K-1,d) Using the iris dataset as an example, we know that d=4 (petal ...
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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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T-tests vs multiple comparison tests vs bonferroni in ANOVA?

I'm taking a course in experiment design and I'm having a hard time grasping the comparative usefulness of t-tests, multiple compariseon tests and bonferroni methods. I understand that in using ...
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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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579 views

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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492 views

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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224 views

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 $H_0: \mu_1 = \mu_3$?

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 ...
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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 (...