mean differences

  1. J

    lme in R - how do I get differences in mean values?

    Hi, my data structure is as follows: Participants experienced 8 different situations and answered the same questionnaire about their experience in each situation (the questionnaire comprises 8 dimensions, e.g. "positivity"). I wanted to assess how they experienced each situation. Now I want to...
  2. R

    Calculate Standard Error over averaged responses or raw responses?

    Hi, I would like to calculate the standard error of my Dependent Variable. However, I have psycholinguistic data, which uses multiple ppts and multiple items. Thus, there are 2 ways of doing this: either by calculating SE over averaged responses (example 1) OR by calcualting SEs over raw...
  3. P

    Testing mean difference on group means, multiple independent groups/sites

    Hello Talk Stats group, I am trying to find out what statistical tests to run on a set of aggregate data (no individual data) on 3 different groups. My variables are summarized below (but I aam attaching a random example to make it more clear): Group 1 in site 1: Mean value (blood sugar)...
  4. J

    Comparing missing and non-missing subjects for dependent variables

    Hello everyone. I am working with a data-set of a cohort study which has 3 different sets of paired data. For the third visit of the subjects, we have a lot of missing. So, I need to compare the basic characteristics (in the first and second visit) of the missing and non-missing subjects for my...
  5. D

    Regression to compare mean differences?

    Hi everyone, I am doing a project with two different groups (clinical and control). I want to compare their scores on a couple of variables (ex: body image disturbance), while controlling for age and BMI. My committee member recommended I do a regression, and noted that it would allow me...
  6. J

    Working around a significant Levene's test in an ANCOVA?

    Hi there, I'm working with some data in which I'm looking for mean differences across 15 subject categories of data on a variable (Clicks) that also covaries with another (Time). I'm trying to control for Time to neutralize its effect on the mean differences in which I'm interested. I've...