mixed models

  1. C

    Experimental Design help

    Been running around in circles with this for a while. I am trying to figure what sort of design I have and how to go about analyzing it. Any help would be great. Details are below. Sample Date, 3 levels, fixed Field, 2 levels, assumed to be random from a larger population. For each sample...
  2. E

    How do I enter the data and which tests should I use in SPSS? Am very lost!

    Hi everyone, Parts of my question may seem rudimentary but the more I read, the more confused I get so I am going to completely spell out my experiment. In my study, I have created 4 conditions by crossing 2 factors- 1) comparison type 2) pricing. Each have 2 levels. My questionnaire had...
  3. A

    Repeated measure mixed models HELP PLEASE!!

    Hi to everyone! I am new to the forum! Very briefly, my problem is as follows: I started a research on videogame exposure and morality. I used exposure to videogames as IV and a measure of morality as DV. The scale used to measure morality has a 5 sub-scales. In a first step of...
  4. A

    Regression analisys with Mixed models - Help!

    Hi to everyone! I am new to the forum! Very briefly, my problem is as follows: I started a research on videogame exposure and morality. I used exposure to videogames as IV and a measure of morality as DV. The scale used to measure morality has a 5 sub-scales. In a first step of...
  5. K

    interpreting random effects

    I have have measured the trait frequency for a "mountain" associated allele across a number of sites and years. In my (glmer) model I have summarized the allele frequency by site and year as the dependent (binomial) variable and specified site and year as random effects. The fixed effects are...
  6. B

    [SPSS] Mixed Models - How To?

    Hi everybody, I've trying to understand how linear mixed models work within SPSS and how to set up my data to run through one. Ive read the appropriate section in Andy Field's SPSS (and sex drugs and rock 'n roll!) textbook but I not quite understanding how this translates over to my data...
  7. E

    simulating a repeated measures ANOVA with mixed linear model analysis

    Hi all, I have a data set with two within subject variables, word category (2 levels) and time (3 levels), and I have a between subjects variable, namely group (2 levels). My dependent variable is reaction time (RT). If I run three separate repeated measures ANOVA for the three different...
  8. C

    Partially Balanced Designs & Mixed Model ANOVA's

    Nevermind. Found the answer I needed. Mods can delete this thread.
  9. G

    Stratification criteria mess up the use of a random factor?

    Hi! In my study on kelp I want to see how wave exposure and current (both continuous variables) affect kelp physical measures along the Norwegian coast. To assure a balanced design, I stratified my study area into 9 different classes, defined by all combinations of three levels of wave...
  10. M

    Wikipedia edits across time

    Hi, I'm having a hard time trying to analyse my data. I have measured the level of anxiety for each edit to a Wikipedia page, and I am considering the first 4 days since page creation. I also have large differences in the number of edits in different days: 500 edits on day 1, 300 on day 2...
  11. J

    Interpreting main effects in long. mixed model when interactions w/ time are in model

    I am running a mixed effects longitudinal model with linear and quadratic time effects and a continuous outcome. I have a covariate that has a significant interaction with time-squared, so obviously the linear interaction and its main effect are left in the model. When interactions are in the...
  12. W

    Mixed models in SPSS -- swapping predictor and predicted?

    Hi, I'm working on a project where I have repeated measures of a (continuous) IV and DV. At each measurement "time" I would like to predict the DV from the IV. I also have a few categorical IVs that do not vary across measurements. My goal is to see if the strength of the relationship...
  13. J

    Linear mixed model without random or repeated effects? GLMZ?

    Hi, I'm working on a dissertation, of which many chapters have longitudinal data and I've been using linear mixed models to estimate growth. I also have some non-longitudinal data (i.e. cross-sectional) that I'd like to estimate growth with in a similar way. The cross-sectional data spans a...
  14. J

    Mixed Model Covariance Structure

    I have a study with a somewhat unique experimental design which I would like to used Mixed Modeling to analyze. All subjects in the study were tested at baseline. Three repeated measurements (dependent variable) were collected on them under controlled conditions (ie, Pre-Exposure, During...