Cannot run ANOVA, but can perform GLM with the same datat

[IlzeD]

Hi everybody,

I absolutely love Jamovi. However, I struggle with some difficulties time by time. I not that difficulties are most likely caused by my not-expertise.
Now I work with data set having 2 factors one of which has only 2 groups (two genotypes). When I try performing ANOVA, I get SS=0 and dF NaN for factor having 2 groups.
At the same time, when I perform GLM with the same data, I get a nice output of ANOVA results.
So far I know that mathematically there is no difference between ANOVA and GLM (isn't it?). However, I am confused why ANOVA doesn't work for my data. Any ideas?

The second thing - is it somehow possible to get single-factor ANOVA output containing sum of squares and Mean square?
Many thanks in advance,
Ilze

[mcfanda@gmail.com]

Hi
would you like to share an example of this issue?

[IlzeD]

Hi, how can I share an example? What shoul I provide?

[mcfanda@gmail.com]

the .omv file containing the analyses that create the issue

[IlzeD]

Example.omv

(8.08 KiB) Downloaded 378 times

I submit my .omv file. Sorry, factors and variables have names in my language. The variable I struggle with is "skirne" - it has two levels. I want to run factorial ANOVA for "Skirne" and "BarotneTrauks" and get trouble with it for any variable (let's say "FWaugsMg"

[MAgojam]

Hi @IlzeD,
the problem you reported is due to the presence of some characters used in your language.
In this case the first two characters in the variable name.
As you can see in the attached screenshot, deleting them from the variable name made it possible to get the correct statistic.

tempsnip.png (69.51 KiB) Viewed 9267 times

Cheers,
Maurizio

[IlzeD]

Hi, Maurizio.

Thanks a lot for your help, it really works. However, I remain confused - why it is possible to run one-way ANOVA and GLM with the same factor name (just curious).

What about my second question? is it somehow possible to get single-factor ANOVA output containing sum of squares and Mean square?

Ilze

[jonathon]

Thanks a lot for your help, it really works. However, I remain confused - why it is possible to run one-way ANOVA and GLM with the same factor name (just curious).

that i am not sure about. it looks to be a bug in R. i'll look into it. i'm reasonably confident you'd only experience this issue under windows.

What about my second question? is it somehow possible to get single-factor ANOVA output containing sum of squares and Mean square?

run a second ANOVA and only specify a single factor? (perhaps i don't understand the question)

cheers

jonathon

[IlzeD]

Hi, Jonathon.

Actually, my question is very simple I run one-way Anova (with one factor or grouping variable) and I get output table containing only F value Df1 and Df2 and p value. I wonder if it is possible to get output similar to excel, SPSS and similar ANOVA outputs that contain SS and MS values? Between and within groups?
I apologize if my questions are dumb I am not a statistician, i just do a routine analysis of my data

Example.omv

(13.1 KiB) Downloaded 336 times

Cheers,

Ilze

[jonathon]

use ANOVA, rather than One-way ANOVA, and simply specify a single factor. like this:

Screen Shot 2021-11-12 at 20.56.26.png (178.75 KiB) Viewed 9138 times