models

  1. D

    Idea of statistical analysis for a particular design

    Hi all, I really need your expertise! Here a set of data obtained from a study: there is 16 participants. Each participant had 3 successive lab visits. During each visit, they consume one drink : either the Drink 1, Drink 2 or Drink 3 (control). The order of drink administration is randomized...
  2. U

    Multi-state models: help?

    Hi, I’m a statistics BS student familiar with survival analysis. Can anyone explain to me what are multistate models, how they are used in survival analysis and what’s their relation with competing risks models? Thank you in advice.
  3. S

    Nested vs non-nested model?

    Hi all, I am running a confirmatory factor analysis and trying to work out if my two models are nested or not - this will be important for me to decide how I compare the models (e.g. using just the AIC and CFI statistics to compare the two models, or whether I can also use the chi-square...
  4. C

    What technique to use?

    I am studying modeling, and I am looking for a good technique to optimize an insurance process, but I am not quite sure how to accomplish what I want to do. I have a dataset with several categorical variables (policy characteristics) and one numerical variable (historical losses). What I...
  5. G

    unconditional expectation for GARCH model with normal inovations

    Hi i have been asked to find unconditional expectations and then a recursive relation. I think I have started well but i am confused at how the recursive relation is made up. this is then to be used with a GARCH model i am working on. details of question: d(t) = mu + sigma(t)Z(t)...
  6. C

    how to determine what test to use for a project?

    I'm trying to determine if there is a statistical significance in hospital admission rates (asthma and bronchitis) before and after tobacco regulations went in to affect. I got the crude and adjusted rates with the 95% Confidence Intervals. Can I just use the 95%CIs to show statistical...
  7. D

    Binomial model with 'complete separation' ...?

    Hello All, I have a data set that is similar to this.. structure(list(d.in.p = c(4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L), time2 = c(0, 0.30209836793605, 0.292033542976939, 0.00731537389688806, 0, 0, 0.0249544211485871, 0, 0.368636194723151...
  8. T

    Number of variables that can be included in an exact logistic regression

    I'm currently analyzing a dichotomous outcome using a small dataset of only 100 individuals. the outcome occurs in only 25 individuals and I have some predetermined confounders that I would like to adjust for. I know that I am limited by, at most, 2-3 variables if I were to model using a...
  9. S

    GAM with Gamma distribution-Default Inverse Link or Log-Link?

    solved. thank you!
  10. S

    Which method to compare models with truth?

    Hi all, Edit: First I must say sorry for the ridiculous spelling mistake in the title! I wish I could go back and change 'two' to 'to'. I have only just come across this forum while searching the net for some info - it looks fantastic so I'm hoping I'll get plenty of use out of it in the...