jamovi

Let me start by thanking the creators for providing jamovi!

I am trying to run a Fisher's exact test on a fairly large dataset (with many expected frequencies <5). However, the test does not appear to run (a P value is not appearing). When I remove some data (e.g., entries with frequencies >10), the test runs properly. I have tried to let my (fast) computer run for a long time, but still no P value is appearing. Is there perhaps a maximum dataset size for this test in jamovi?

Hi

Fisher Exact Test apply only to small tables, in jamovi only for 2 x 2 tables. If you are interested in species x sex, Fisher test is not appropriate

Thank you for your reply. However, jamovi has no problems performing Fisher's exact tests on larger tables than 2 x 2 and the test appears appropriate for my data. I just do not understand why it does not run in the example that I gave, whereas it does run when I remove a small number of rows.

Victor2 wrote: ↑Wed May 24, 2023 1:37 pm However, jamovi has no problems performing Fisher's exact tests on larger tables than 2 x 2 and the test appears appropriate for my data...

Hey @Victor2,
what you say is right and generally there is final p-value in the table.

The analysis of your data does not end as expected with a p-value, because the default work area is insufficient for the necessary calculation process (unfortunately, there is no note in the table regarding this lack of p-value ).
I can tell you that I'm talking to @Jonathon about a code fix based on a possible workspace increase or (what I prefer) switching to a Monte Carlo simulation, when this error occurs, to arrive at a p-value final in table.

In the screenshot the result of a Monte Carlo simulation with data that could be yours. Thanks for reporting this to us.

Cheers,
Maurizio

Hi, you are right! Look at viewtopic.php?p=7799&hilit=fisher+exact+test#p7799.

Many thanks for solving the mystery @Maurizio, much appreciated! I will be looking forward to the code fix.

MAgojam, perhaps a stupid question, but how have you been able to do the Monte Carlo simulation in jamovi? When I used the Rj module for the simulation, I end up with a "FEXACT error 40. Out of workspace".