Tagged Questions

0
votes
0answers
85 views

ANCOVA (GLM) versus Mixed Linear Model with covariate measured at both pre- and post-treatment (in SPSS)

I'm trying to analyze a pre/post study with 4 treatment groups. The Dependent Variable, Speed, measures how quickly a person's facial expression reaches peak intensity; this measure is normally ...
6
votes
3answers
227 views

Baseline differences in RCT: Which variables (if any) should be included as covariates?

I recently completed a study whereby I randomly assigned participants to one of two treatment groups. I tested participants at baseline, immediately post-intervention, 1 months, and 4 months on a ...
2
votes
0answers
120 views

Mixed model in R with paired design and covariates

I make habitat suitability models for animal species. The purpose of my research is to investigate the accuracy of different models. I clearly have a nested design: accuracy_measure -> response ...
7
votes
2answers
189 views

Large number of correlations with MRI region of interest (ROI) variables: What adjustment should I perform?

In our group, we have measured grey matter volumes of about 20 regions of interest (ROI) and frequency of cannabis use. Now, we would like find out whether cannabis use is associated with grey matter ...