# kruskal wallis

1. ### Stats analysis struggling

Hi, I am conducting an experiment where I am assesing 4 groups undergoing 2 treatments. 3 groups have recieved same treatment and 1 group has recieved the other treatment. I have averaged values of the 3 groups. It is a pre and post experiment. I want to compare the data for both pre groups...
2. ### Statistical Analysis using Minitab

Hi, I am conducting an experiment where I am assesing 4 groups undergoing 2 treatments. 3 groups have recieved same treatment and 1 group has recieved the other treatment. I have averaged values of the 3 groups. It is a pre and post experiment. I want to compare the data for both pre groups...
3. ### Testing normality of distribution: Shapiro-Wilk's test/Levene's test?

I have data from an experiment with 5 conditions. The goal is to compare the impact of treatment on dependent variables between the conditions. To determine whether to use ANOVA or non-parametric equivalents, I conducted Shapiro-Wilk's test. It shows that the data is not normally distributed, so...
4. ### One way ANOVA vs Kruskal Wallis

Hi, I am comparing four groups (measurements of bone thickness and other bone parameters). The distributions are normal (Kolmogorov–Smirnov test) and variances equal between groups (Levenes test). I have 7 samples in each group. As I see from the literature this would call for a parametric...
5. ### Post-hoc power analysis for a Welch ANOVA and also a Kruskal-Wallis test.

I planned to analyse some data with several ANOVAs (I have many different dependent variables), but much of the data violates the ANOVA assumptions, so they require Welch's ANOVA or the non-parametric Kruskal-Wallis test instead. Using SPSS, I generated effect sizes (partial eta squared) and...
6. ### Statistical test for ranked data among 3 groups - ANOVA or Kruskal-Wallis?

Hi all, I've read several books but I am not sure which statistical test to apply and whether my thinking is correct so I would greatly appreciate any help. I conducted a survey among three independent groups (managers N=110, analysts N=105 and investors N=80) and in one question I asked...
7. ### Test for ranked data among 3 different groups - ANOVA or Kruskal Wallis in SPSS?

Hi all, I have read several books but I am not sure if my thinking is correct and would greatly appreciate if someone could help me. I conducted a survey among three independent groups (managers N=110, analysts N=105 and investors N=80) and in one question I asked them to rank, based on...
8. ### ANOVA? Looking at percentage habitat use (6 different habitats) across four seasons

Hi, I am trying to look at whether habitat use of 6 different habitat types differs across 4 seasons. I have managed to run ANOVA tests but I'm not convinced this is correct. The code I have been using is as follows; an.aov=aov(Month~Heathland) an.aov summary(an.aov)...
9. ### Comparing habitat use across two different locations - mann whitney U?

Hi, I'm really stuck with what test to use with my data. I have data on habitat use of 6 different habitat types across 2 locations and I'm unsure what test is most suitable. I thought initially mann whitney U but this doesn't seem to be working for me. I've attached the table below so you...
10. ### SigmaPlot 12.5 - Kruskal-Wallis followed by Dunn's post hoc - how do I get p-value?

Hello, I've been using SigmaPlot12.5 to run nonparametric Kruskal Wallis test, followed by Dunn's post hoc. When I get the read out for "All pairwise comparisons," the results only tell me if the P-value is less than or greater than 0.05. Is there a way to have the program provide the specific...
11. ### How to do a bonferroni correction after Kruskal Wallis H

Hello everyone! My knowledge in statistics being very poor, I would like to ask for your valuable help! Wanting to check any differences between the anwers given in a 5-point likert type question measuring attitudes towards new technologies and the years of service of teachers (0-5 / 6-10 /...
12. ### Proper analysis for group differences in proportion scores

Hello all, I am running analyses looking at group differences in the proportion of time kids were distressed in a task. I have a task that has been broken up in to 10s time slices and kids receive a score of 1 in each slice they evince distress. To create my outcome variable, I am dividing...
13. ### choosing the right statistical test for comparing data, when do you use which test

Hello all, I would like some feedback on the right approach of analysing data, comparing means of groups of data. Currently I work with the following 5 steps to analyse my data. Is this approach correct or how do you analyse your data if you do it differently? 1) I test for normality...
14. ### Error bars don't overlap but aren't significantly diff. - interpretations/reasons?

Hello all, I'm struggling to understand/interpret my graph and kruskal wallis test. Basically, I've created a bar graph which looks pretty good. There are 5 bars, each with error bars, and none of the error bars overlap. All of my 5 groups look significantly different. HOWEVER, when I do a...
15. ### How to plot non-parametric data with multiple time points?

Hello, I analyzed some physiologic data (blood electrolyte levels etc) which was fairly skewed, so I used Kruskal-Wallis to test for differences between groups. I originally plotted the mean and SD, but I learned that plotting the median is more suitable with skewed data. My question is...
16. ### ANOVA or Kruskal Walli

Hi! I have measured respiration in 3 treated and one untreated control cell line with N= 27, 25, 31 & 31. Can I use a one way anova or should I use a kruskal wallis test? Or are there any better options? Thanks J
17. ### Kruskal-Wallis & Regression: unequal n, unequal sd & non-normal dep.var.

Hello and thank you for reading this thread! My problem is as follows: I conducted a simple experiment to check for the effect of gender and gender pairing in the outcome of a game (the ultimatum game, I won't bother you with unnecessary details). Important for my question to you, is...
18. ### t test or ANOVA, ? normal distribution

I have an experiment on cancer cell lines. There are 7 cell lines. Each cell line is treated with a different concentration of the same drug. The average concentration that killed half the cells in each cell line is calculated, along with a standard deviation as follows: Cell Line //////...
19. ### Multiple comparison test, with ambiguous labels/ranks

In a clinical study, I have patient's health condition labeled as grade 1, 2, or 3. Some patients are labeled as "Either 1 or 2" by the doctor, meaning the doctor considers both grade 1 and 2 as valid descriptions of the patient's health condition. When performing say a Kruskal-Wallis test...
20. ### Kruskal Wallis test and problem with zeros

Hi. I am conducting a biological research about species abundance variations between different hours and localitions. I am comparing 11 different locations and 5 different hours. Independent variables are hour and locality. Dependent variables are abundances of each species found in...