Linked Questions

1 vote
2 answers
290 views

T- test for A, B, C, D

As you know, Student´s t-test is only valid for a pair of variable/experiment. for instance, we can do t-test(A, B). Now, I need to test whether variables A, B, C, D are close to each other or not. ...
user avatar
  • 211
1 vote
2 answers
2k views

How can I interpret a significant one-way repeated measures ANOVA with non-significant pairwise, bonferroni adjusted, comparisons?

I have a dataset with one factor consisting of four levels. I've run a one-way repeated measures ANOVA on the data, which came out significant. However, for the follow-up pairwise, bonferroni adjusted,...
user avatar
  • 668
0 votes
2 answers
106 views

Two way ANOVA unbalanced and nested TYPE III. Significant results

I have an unbalanced design with nested factors. In particular, the nested factor is obesity, with levels: of obese and nonobese. The other factor is group: women with syndrome, control women, and ...
user avatar
0 votes
2 answers
78 views

Difference in Significance for a T and F test

After conducting a one way ANOVA, an F-test indicates that I should retain the null hypothesis (no two means differ), but the t-test (in line with the theory) tells me that the groups I tested are ...
user avatar
  • 1
13 votes
1 answer
1k views

How much smaller can $p$ values from ANOVA's $F$-test be vs. those from multiple $t$-tests on the same data?

Intro: Having noted the attention received today by this question, "Can ANOVA be significant when none of the pairwise t-tests is?," I thought I might be able to reframe it in an interesting way that ...
user avatar
  • 11.6k
6 votes
1 answer
146 views

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 ...
user avatar
  • 2,196
5 votes
1 answer
123 views

What general pattern in the means would produce a non-significant ANOVA result but a positive Tukey?

Why would the results of the ANOVA be non-significant, while a pair-wise comparison using Tukey's Wholly Significant Difference (WSD) is significant? Is their a general pattern in the means of the ...
user avatar
4 votes
1 answer
8k views

Significant ANOVA interaction but non-significant pairwise comparisons [duplicate]

I ran a two-way ANOVA and got a significant interaction. I ran a Tukey.HSD() post-hoc test in R and no pairwise comparisons were significant. Is this an error on my ...
user avatar
  • 480
3 votes
1 answer
503 views

Transitivity of statistical significance

Say I have three sets of observations, $A$, $B$, and $C$ (say, the heights of Australians, Americans and Brits). I assume that they are all normally distributed, independent etc. I perform two-sided ...
user avatar
3 votes
1 answer
285 views

Wald test and Type III test don't agree?

I am having trouble understanding the output here. In the green table, it seems like SAS is saying "Gender F" and "Gender M" are not significant. However, in the blue table, seems like it's saying ...
user avatar
  • 1,406
2 votes
1 answer
550 views

Multiple tests plus correction versus ANOVA - is one always better?

A colleague was using three pair-wise t-tests plus Bonferroni correction to detect any differences in the means of three groups. My first response was to tell him to use an ANOVA instead, since my ...
user avatar
0 votes
1 answer
30 views

Significant result in Kruskal-Wallis but non significant results in post hoc test

I got significant result after Kruskal-wallis, but when I applied two post hoc tests (Dunn test and Krystalmc), I obtained non significant results! How to explain that?
user avatar
  • 161
0 votes
1 answer
101 views

Is it possible to get non-significant post hoc test in a significant ANOVA test while the unpair t-tests are significant? [duplicate]

I conducted One-Way ANOVA to compare means in 4 groups. The ANOVA was significant, but the post hoc tests were non-significant. Then, I applied unpair t-tests to compare each group to the lowest group....
user avatar
81 votes
0 answers
64k views

How can a regression be significant yet all predictors be non-significant? [duplicate]

My multiple regression analysis model has a statistically significant F value however all beta values are statistically non-significant. All the regression assumptions are met. No multicollinearity ...
user avatar
  • 811
0 votes
0 answers
94 views

Anova Post Hoc Test

I am running an anova in SAS on the average hours worked for a country. With those countries grouped into 3 regions. When I run the anova I get a F value of 3.64 and P-value 0.0379. With these ...
user avatar

15 30 50 per page