search for: tigol

Displaying 3 results from an estimated 3 matches for "tigol".

2004 Jan 08
3
Strange parametrization in polr
...ata( housing ) hnames <- lapply( housing[,-5], levels ) house.plr <- polr( Sat ~ Infl + Type + Cont, data=housing, weights=Freq ) summary( house.plr ) newdat <- expand.grid( hnames[-1] )[1:5,] cbind( newdat, predict( house.plr, newdat, type="probs" ) ) # Baseline probs: diff( c(0,tigol( c(-0.4961,0.6907) ), 1) ) # First level of Infl: diff( c(0,tigol( c(-0.4961,0.6907) + 0.5663922 ), 1) ) # But the change of sign for eta is needed to reproduce the fitted values: # Line 2: diff( c(0,tigol( c(-0.4961,0.6907) - 0.5663922 ), 1) ) # Line 5: diff( c(0,tigol( c(-0.4961,0.6907) - 0.56639...
2001 Dec 18
2
Aranda-Ornaz links for binary data
Hi, I would like apply different link functions from Aranda-Ordaz (1981) family to large binary dataset (n = 2000). The existing links in glm for binomial data (logit, probit, cloglog) are not adequate for my data, and I need to test some other transformations. Is it possible to do this in R? And how? Thank you for your help, /Sharon
2011 Apr 27
2
ROCR for combination of markers
Dear list   I have 5 markers that can be used to detect an infection in combination. Could you please advise me how to use functions in ROCR/ other package to produce the ROC curve for a combination of markers?   I have used the following to get ROC statistics for each marker. pred <- prediction(y$marker1, y$infectn) perf <-performance(pred,"tpr","fpr")