search for: tahtawi

I am trying to develop a prognostic model using logistic regression. I built a full , approximate models with the use of penalization - design package. Also, I tried Chi-square criteria, step-down techniques. Used BS for model validation. The main purpose is to develop a predictive model for future patient population. One of the strong predictor pertains to the study design and would not

Dear friends, Ecdf used to work nicely before. e.g. ecdf(df1v[,c(1:6)],group=df1v$trt,q=.5,col=1:2,label.curves=list(keys="l ines"), datadensity="rug") but now it does not work at all, even for a simpler code??? By the way, I used the same libraries. Thanks for your help. Ahmed [[alternative HTML version deleted]]

Dear friends, I need to fill in (duplicate the whole record) the missing days with the same record values as long as AE is the same value (i.e. "1"), once AE value changes, the process of duplication should proceed with the new AE value till it changes again. e.g. I need to fill in records: day 18-day 44, all the records are carried with the new AE value of "0". At the

Hello, I have been informed that there is no R package for the stratified Wilcoxon's rank sum test (Van Elteren's test) with the locally best weights. I need to use the alternative test to a clinical endpoint where the distribution approximate normal distribution, and compare to the regular ANOVA. I have been directed to use SAS with PROC FREQ with the SCORES=modridit option and CMH2