1
vote
1answer
61 views

Statistically prove the effectiveness of a treatment using GLM repeated measurements

I have two lots of samples: one is the control lot and the other undergoes some treatment. I did three measurements for the samples: one at the initial time (T1) ...
0
votes
1answer
41 views

Best way to estimate a regression with reaction times

I have reactions times in a no-normal distribution, so I am using logarithms. Which can be the best way to estimate a regression? Later, I would like to plot the results according to the age of my ...
1
vote
0answers
55 views

Generalized Linear Mixed Model

I have three independent variables (all binary) and two interaction variables that I would like to test for their effect on the dependent variable "Awareness_level". This dependent variable is also ...
0
votes
0answers
16 views

Power analysis for log-gamma model

I fitted a generalized linear mixed log-gamma model in SPSS with 1 fixed factor (binary), patient ID as a random intercept and a continuous variable as (fixed) covariate. How can I calculate the ...
1
vote
1answer
86 views

Inverted SPSS results: Logistic regression command vs. Genlin?

I want to do a logistic regression in SPSS. However, since I analyse unemployment spells the subjects are sometimes repeated (violating the independence assumption of the regression). One way of ...
0
votes
0answers
141 views

Customizing a Split-Plot Model in SPSS

I am having a little trouble with SPSS in a rather complex design. I have to analyze an experiment with 1 within factor and 3 between factors. I don't want to test all possible effects (just the 4 ...
3
votes
0answers
234 views

What does the Scale parameter mean in linear regression?

I have started to use the GENLIN procedure in SPSS more than any of the specific dialogues, but I don't understand the Scale parameter or why it has the effects it ...
5
votes
4answers
947 views

What regression analysis should I perform on my data and why?

I am a law student researching which factors influence the CSR (corporate social responsibility, GSE_RAW) behavior of companies. As my studies didn't offer any ...
4
votes
2answers
668 views

Generalized Linear Model in SPSS with common values among predictors treated as subpopulations. Why?

I am teaching a class on logistic regression with SPSS. The textbook supplies a sample data set with a binary predictor and two numeric covariates. The sample contains 1000 rows and a number of these ...
5
votes
1answer
954 views

Interaction in generalized linear model

I have 2 continuous variables as my predictors and the interaction between them, so 3 effects all together (when I center my predictors only the interaction is significant). I am using a binary logit ...
6
votes
1answer
383 views

Wald vs. LR $\chi^2$ tests in SPSS generalized linear models

I'm using the generalized linear models function in SPSS with a normal distribution and identity link function. If I choose the likelihood ratio $\chi^2$ statistic, I get the same results as the ...
11
votes
3answers
6k views

Difference between generalized linear models & generalized linear mixed models in SPSS

I am wondering what the differences are in SPSS between analyze-> generalized linear models-> generalized linear models & ...
3
votes
1answer
215 views

Why does -2*LL differ when using binary logistic regression vs GLM binary logistic in SPSS?

I'm comparing plausible models selected a-priori to predict a binary response variable. I used binary logistic regression in SPSS20 and obtained AIC=-2*LogLikelihood+2k where k is the number of ...
1
vote
1answer
150 views

Basic information or texts required about modelling k bernoulli trials

I have been presented with a dataset comprised of individuals and the number of teeth they have had extracted. The maximum is 32, and almost half of the data are zeros. I have been asked to suggest an ...
7
votes
3answers
6k views

Sidak or Bonferroni?

I am using a generalized linear model in SPSS to look at the differences in average number of caterpillars (non-normal, using Tweedie distribution) on 16 different species of plants. I want to run ...
2
votes
1answer
395 views

Running transformed data with a Generalized Linear Model in SPSS

I am running a generalized linear model in SPSS on data highly skewed to the right with a bunch of zeroes (average # caterpillars per tree species branch sampled) so I decided to use the Tweedie ...
1
vote
0answers
373 views

Fitting generalized linear model with covariate

In our experimental design, we are assessing the effect of TMS on decision making. Our data is not normally distributed because our assesment test results in mean count data (ultimatum game). Besides, ...
3
votes
1answer
309 views

Half-normal distributed DV in generalized linear model

My dependent variable is, by origin, absolute residual* left after some regression; it is distributed half-normally. Now I plan to use Generalized linear model in SPSS (GENLIN) to regress it on some ...
1
vote
1answer
920 views

Z score transformation for testing group differences in correlations

SPSS Help provides the following help for testing group differences in a correlation, using the GLM approach. See link. It first requires that X and Y are transformed into z scores. Question: When ...