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...the initial gradient > p = summary(maxLik(fr,start=c(0,0,0,1,0,-25,-0.2),method="BFGS")) Error in optim(start, func, gr = gradient, control = control, method = "BFGS", : initial value in 'vmmin' is not finite The codes are as follows yogurt = read.table("yogurtnp.csv", header=F,sep=",") attach(yogurt) dim(yogurt) choice = yogurt[,2:5] price=yogurt[,14:17] feature=yogurt[,6:9] n = nrow(yogurt) constant = rep(1,n) yop=cbind(constant,feature[,1],price[,1]) dan=cbind(constant,feature[,2],price[,2]) hil=cbind(constant,feature[,3],price[,3]) wt=cbi...

...e following code for nested logit and got a message that Error in optim(c(0, 0, 0, 0, 0.1, -2, -0.2), fr, hessian = TRUE, method = "BFGS") : initial value in 'vmmin' is not finite What does this mean? and how can I correct it? Thank you June > yogurt = read.table("yogurtnp.csv", header=F,sep=",")> attach(yogurt)> dim(yogurt)[1] 12784 25> choice = yogurt[,2:5]> price=yogurt[,14:17]> feature=yogurt[,6:9]> n = nrow(yogurt)> constant = rep(1,each=n)> yop=cbind(constant,feature[,1],price[,1])> dan=cbind(constant,feature[,2],pri...

Hi All, I've been having a little trouble with creating a loop that will run a a series of t.tests for inspection, Below is the code i've tried, and some checks i've looked at. I've used the get(paste()) idea as i was told previously that the use of the eval should try and be avoided. I've run a single syntax to check that my systax is correct and works without any problems