Recent content by rezzak

1. Exp(B) or CI values with the letter "E"

Dear all, I am running a Multinomial Log. Regression. Everything seems fine but I do not understand when Exp(B) oder CI values are like 1,000E-013. I see this result although, the goodness of fit of the overall model is appropriate. For example in: B=-107,4, p=0,031 Exp(B)=1,000E-13...
2. Is Kruskal Wallis really needed?

Dear all, I really do not see why we need Kruskal-Wallis test at all. In terms of the distribution, only platykurtic distribution may increase type 1 error. When the break the homogeneity of variance we could use Welsh or Borwn-Forsythe. We have a posthoc test suitable for all types of data...
3. IV problem of MANOVA

Hi everybody, How can we know how many IVs can we put in MANOVA? I have 1 DV with 3 groups, and as IV, the neuropsychological test (CERAD) scores with 10 subtests (MMSE, TMT, BNT, verbal fluency etc.). Of course these subtests are correlated with each other. Do you think I should use...
4. Boston Naming Test

Dear Friends, I am trying to define the differences of two means in Boston Naming Test (BNT). I want to conduct a multipl regression with education and age as covariates. However, The raw scores of BNT are very skewed due to the high ceiling effect. I have found heteroscedasticity in my...
5. Age and gender effects in neuropsychological tests

Dear friends, I will try to ask it simple: Dependant variable: scores of a cognitive test (scale) independant variables: brain atrophy (yes,no), family history (yes,no), gender (m,f), age(scale) I am searching if brain atrophy group performed worse in cognitive tests. However atropy...
6. Durbin Watson related with outliers?

I am trying to run a multiple regression with a sample data belongs to a cohort of 500 subjects. My dependant variable is a psychological score (scale), independant variables are age(scale), sex(nominal) and education(scale). I run the test and Durbin-Watson was 1.99 which is good but I had 2...