1. Q

    AIC models

    Hello, If I have a model with an aic of 8765 and another model reduced with two variables less with an aic of 8823. Can I accept the reduced model with the AIC of 8823? What is the difference between the two AICs that should not be exceeded? Thank you
  2. M

    Lagged values in a LASSO regression

    Hi all, While working on the statistics for my thesis, I became confused while building up my model. I am currently working on a forecasting model with the use of a LASSO regression. The model is build as follows: the unemployment rate is the dependent variable and as exogenous variables I...
  3. J

    What are the downfalls of selecting most parsimonious model using AIC?

    Hi all, I am rather new to statistics, but I am reviewing a paper that applies the most parsimonious model for logistic regression using Akaike’s Information Criterion. It is a clinical study in ~200 patients and covariates assessed are mostly categorical variables. Results are opposite of...
  4. L

    Firth regression and AIC-based model selection

    Dear all, when using Firth's bias reduction method (Firth 1993) to fit logistic regressions, is it possible (sensible) to compare models using AIC? In R, two main functions ("logistf" and "brglm") can handle Firth's method. MuMIn allows to extract AIC(c) values for both functions, so my first...
  5. A

    How to run AIC and Logit on Panel Data?

    I've data for 10 banks over a period of last 10 years. I've financial ratios for each bank corresponding to each financial year. There are 20 such ratios. I would like to run AIC on these ratios to find 7 or 8 most significant ratios and then run binary logit on the panel data of these...
  6. M

    Mixed Logit Regression Problem with AIC / BIC

    Hi, I am new to this forum and have trouble with my mixed logit regression model. I have conducted an experiment with 169 participants who each performed 5 brand choice decisions (Buy brand A vs. Buy brand B). In each decision, there was a different product type (e.g. laundry detergent...
  7. A

    Can AIC values be combined?

    Hello! I have hunted far and wide on the net in an attempt to answer this. Essentially, I'm trying to combine two AIC scores from different parts of a single data set. I have two models (of the same type: nonlinear least squares fitting a growth curve to population data) that each predict...
  8. E

    Dredge in R

    Hi everyone, My knowledge in R statistical software is poor. Could eventually someone help me to understand which way I do dredge in R? How do I present all top models within 2 AIC and model averaged parameter estimates? Thank you in advance, Tom
  9. R

    Latent Growth Curve and covariates

    I'm examining latent growth curves in Mplus. My dependent variable is continuous, measured over three time points. I have a great unconditional model, and now I want to examine multiple time-invariant predictors on the latent intercept and slope. If I add the predictors, how do I evaluate if...
  10. P

    [STATA - Lag length criteria]: How can I explain the results?

    Good evening everyone. I got different output from the code: forval i = 1/118 { varsoc Illiq`i', maxlag(10) } that describes AIC,BIC,... lag information criterion, but I don't know how I can interpret them. How can I choose the correct number of lags on the basis of all these output...
  11. T

    Sequential Variable selection help

    how do I do Sequential Variable selection in R please help thank you
  12. M

    Model comparison in psychophysics with multiple participants

    Hi, I have a quite general methodological question about model comparison. I ran a psychophysical experiment in which each participants performed ~500 trials of a perceptual decision task. My observation are reaction times. I want to compare several possible model to find which one explains...
  13. B

    Using "AIC per sample" to compare logistic regression models

    I'm generating nested models using logistic regression and comparing them by AIC. One issue that arises is that not all samples have all independent variables coded. For sake of discussion, let's assume no imputation of missing independent vars: those samples just get dropped when generating...
  14. I

    Model reduction justified?

    Hi! I'm working with cox proportional hazard models in R and I'm trying to find the minimum model. I have a very simple question but I cannot find a direct answer:). These are the models and the result of the anova: anova(model1,model2) Analysis of Deviance Table Cox model: response is...
  15. C

    AIC on GLMM pscl package

    Hello, i'm working with GLMM oon the pscl packge and i needed the AIC. How to extract it?:confused: Example: mmall3 <-glmmPQL(allclues ~ cycloc + male + cycloc * male, data=dados, family=poisson, random=~1|animal/idfid) summary(mmall3) and the results: Linear mixed-effects...
  16. R

    AIC number of parameter

    Dear all, I am new in this forum. I m facing a problem with my AIC. I m using model selection framework (Akaike’s weights) with various type of "Abundance-occupancy" model. It is a family of model which uses mean abundance of species to predict the probability of occurrence. One of these...