[R-meta] N of trials or participants?
Thanks for clarifying. So let's say each subject goes through m trials on some task and either correctly identifies a target or not on a given trial. Let x_j denote the number of trials on which the target was correctly identified by the jth subject and so p_j = x_j/m would be the corresponding proportion of trials. It would be unusual that p_j is reported for the N subjects in the study. Typically, one might have the mean proportion (so: sum p_j / N) and the standard deviation of the proportions. If the subjects are actually in two groups/conditions, then one can just compute a standardized mean difference in the usual manner based on the two means and SDs. The number of trials (m) is not relevant for this. Best, Wolfgang
-----Original Message----- From: Patrizio E Tressoldi [mailto:patrizio.tressoldi at unipd.it] Sent: Wednesday, 01 February, 2023 8:49 To: Viechtbauer, Wolfgang (NP); r-sig-meta-analysis at r-project.org Subject: Re: [R-meta] N of trials or participants? Il 01/02/2023 08:44, Viechtbauer, Wolfgang (NP) wrote:
I think you are using 'trials' in a different way than how I interpreted it. I
understood it as meaning 'studies' (as in 'clinical trials') but you seem to be referring to repeated measurements on individual subjects. Can you describe in more detail what kind of data you are thinking of?
Sorry, as trials I mean number of repetitions of the task, e.g., to guess or identify a target as in many perceptual or cognitive psychological tasks. Patrizio -- Patrizio E. Tressoldi Ph.D. Science of Consciousness Research Group Studium Patavinum Universit? di Padova Padova - ITALY http://www.patriziotressoldi.it https://socrg.org https://orcid.org/0000-0002-6404-0058 https://opensciences.org/about/manifesto-for-a-post-materialist-science Make war history support https://en.emergency.it