Displaying 2 results from an estimated 2 matches for "halflogit".
2012 Aug 10
0
error applying user-defined link function to lmer
Dear R users,
I'm struggling with applying a user-defined link function in lmer. For analyzing data of a 2AFC psychophysical experiment, I would like to model my binary data with a logistic function with a lower limit at 0.5 instead of 0. In a previous question this has been described as a halflogit function. To do so I wrote my own link function and would like to submit it to lmer, however this results in error messages. Below I've listed some of my attempts to solve this problem based on previous postings on this list. I've also added the corresponding problems I encountered with eac...
2007 Aug 10
0
half-logit and glm (again)
...omial( p_{ij}, N_{ij} )
I've generated data using this model, and I'd like to fit it. My data is
a data frame with 3 columns, "response" (0/1), "subject" (a factor), and
"condition" (another factor).
Here is my link definition:
#############################
halflogit=function(){
half.logit=function(mu) qlogis(2*mu-1)
half.logit.inv=function(eta) .5*plogis(eta)+.5
half.logit.deriv=function(eta) .5*(exp(eta/2)+exp(-eta/2))^-2
half.logit.inv.indicator=function(eta) TRUE
half.logit.indicator=function(mu) mu>.5 & mu<1
link <- "half.logit"
stru...