repeated measures

  1. 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...
  2. M

    Use of linear mixed models for within subjects repeated measures experiment

    Hello, I am trying to argue that I used the correct statistical test for a paper that is currently in review. I have formulated a counter-argument, but I'm not an expert so I wanted to make sure I am correct. In my experiment, I measured how long it took for subjects to complete a task...
  3. Z

    Power Calculation using Stata

    Hi, I am involved in a clinical study where I need to ascertain that the study has adequate power. The study aims at understanding the effect of a program on patients. We are required to have a control and a treatment sample. I believe I can recruit about 22 individuals for the study in each...
  4. S

    Two-way repeated measures--post-hoc analysis?

    Hello, I have run a repeated measures two-way ANOVA using SAS. The repeated measure is time and it shows that it is significant in an interaction with one of my factors. How can I do a post-hoc analysis to determine which group is actually significant? I know the usual for regular ANOVAs...
  5. S

    Is the following testable? I think so and have chosen Friedmans test, is it correct?

    Hello TS people, Thanks for talking a look at my question/problem, I am new, you can check out my introduction topic on the appropriate forum. I am planning a set of experiments and would like to be able to present them to my Prof. with a sound set of workable statistics. Predator...
  6. M

    effect sizes: generalized omega squared statistics

    hi all i read this paper http://www.psych.umn.edu/courses/spring06/federicoc/psy8815/lectures/genomegasquared.pdf and based on the following arguments: 1) very small sample size - needs unbiased estimation 2) repeated measures 3) 2 x 2 design decided on reporting the generalized...
  7. B

    repeated measures subject with n>1?

    I am analyzing a repeated-measures dataset in SAS using proc mixed, and I'm stumped about the repeated measures subject. Here's the design of the experiment: I have forest plots, each containing 100 trees, and randomly assigned to contain 1, 2, 4, or 8 different genetic clones per plot...
  8. O

    Not sure about what spss test should I use

    Hi everyone! I would like to ask you a question! I conducted an experiment in which 25 men and 25 women listened to an attractive conversation and picked a photo (between a woman with red and a woman with green shirt) and next, they heard a neutral dialogue and did exactly the same, picked a...
  9. J

    repeated measures MANOVA or MANCOVA?

    Greetings, The study is pretest-posttest control group design, comparing two treatments and a control group (wait list) on 7 outcome variables using a convenience sample with random assignment to the 3 groups (level of treatment is the independent variable). The outcome variables (continuous)...
  10. N

    regression in repeated-measures design with questionnaires as predictors

    Hi everyone, I have 2X2 repeated measures design (congruent/incongruent and negative/neutral). I want to predict the main effects and the interaction using questionnaires as depression, anxiety, etc. what is the best way to run this analysis? does someone have syntax for spss/other software...
  11. D

    Won't Repeated Measures GLM give estimated Standard Deviations ?

    Hello, I am novice so I hope that my question formuling will be understandable.. I am using the RM GLM and wonder whether some option (I doubt) or a syntax command would let SPSS calculate my between subjects factors' estimated Standard Deviations, similarly to the Means and Standard...
  12. C

    Repeated measures or not?

    Hi All, I sampled crickets weekly over 5 weeks from the same population, and measured their body size. Half of the crickets were taken from predator's nests (sampled within a day of being caught), and half were sampled directly from their natural habitat. My research question is: are predators...
  13. S

    Time series or just repeated measures?

    Hi All, I have data on 7 clusters (ie, sites). The date are monthly counts (there is no zero inflation in most of the outcomes of interest...most clusters have a count in the 10s-100s for each month) , from Jan 2004 to May 2010, however only one cluster has data before March 2006. By...
  14. C

    Know what I need to do, but no clue how to do it! Engineering thesis help!!

    Negative Binomial Regression with Repeated Measures possible in SPSS? I'm working on my thesis in civil engineering. I am trying to create an equation to predict the number of crashes along a highway segment using Negative Binomial Regression with Repeated Measures. The way I am trying to...
  15. M

    graphing a 3x2x2 mixed design in SPSS, how?

    Hi, I have a 3-way mixed factorial data set. In this study, an experimenter compared three different therapies for quitting smoking; let's say they are X, Y, Z in two locations (Home and Work). Therapy and location are both between subject variables. Participants were asked to rate their...
  16. M

    General Applications of Various Statistical Techniques for Continuous Processes

    My hope is that people can chip away at the questions raised in the article. All responses are welcome! I have been spending a bit of time trying to teach myself various univariate and multivariate statistical techniques. I would really appreciate a "one stop shop" with a general overview of...
  17. D

    Using Generalized Estimating Equations to test item validity on a scale

    Hi, I am creating a new measurement scale for withdrawal from cannabis, and have daily withdrawal data from 50 people for 1 week before abstinence (baseline smoking as usual) and then for 2 weeks of abstinence. There are 26 items on this new scale, and essentially what I want to is to rank...
  18. K

    Covariance structure question for mixed model repeated measures ANCOVA

    I'm working on a mixed model repeated measures ANCOVA and am working on identifying the covariance structure for my model. I am interested in modeling 2 of my variables as repeated measures, and am wondering if this is even possible. I'm working in SAS, and keep getting error messages telling me...