similar to: Using survreg for Tobit

Dear listserv members, In Croissant (2008) “Panel Data Econometrics in R: The plm Package” the authors seem to indicate that the nlme package for R cannot correctly handle unbalanced panel data: “Moreover, economic panel datasets often happen to be unbalanced (i.e., they have a different number of observations between groups), which case needs some adaptation to the methods and is not

I am hoping that some one might be to tell me whether there are any functions that produce influence measures for lme /nlme objects (i.e those suggested by Lesaffre and Verbeke or Langford and Lewis for multilevel models). Thanks in advance. ----------------------------------------------- Anthony A. Pezzola apezzola@uc.cl (02) 354-7823 Profesor de Ciencia Política Instituto de Ciencia

Estimados, A todos quienes estan insterados y estan en Stgo de Chile les tengo una muy buena noticia. Desde hace ya algunas semanas, nos hemos sentado a la mesa con Alex (Epidemiologo) a discutir la necesidad de desarrollar un curso de R para principiantes. No solo porque es necesario unirse en torno a un projecto como es el R, sino que es una oportunidad para muchos cientificos (como

Hello, I am working on a Tobit Model for a consumer good, left censored with zero. Relation: Sales of product depend on price, promotion (dummy), Season(dummy) and store (dummy) Used standard Tobitmodel with package(AER) vor a 48 week period: tobitmodel<-tobit(SALE~Price+Promotion+Season+Store,data= datatobit) Now I want to predict the values for week 49-52. Used predict device:

Estimados, A todos quienes estan insterados y estan en Stgo de Chile les tengo una muy buena noticia. Desde hace ya algunas semanas, nos hemos sentado a la mesa con Alex (Epidemiologo) a discutir la necesidad de desarrollar un curso de R para principiantes. No solo porque es necesario unirse en torno a un projecto como es el R, sino que es una oportunidad para muchos cientificos (como

I am trying to work out a bootstrapped Tobit regression model. I get the coefficients all right, but they all have standard error zero. And I am unable to figure out why. I know the coefficients are correct because that's what I get when do a Tobit (without bootstrapping). Here's my code: # Bootstrap 95% CI for Tobit regression coefficients? library(boot) library(AER) # for the Affairs

I have an unbalanced panel of daily, county data that is naturally bounded at zero so my intention is to use a tobit. I'm using tobit from the AER package. There is cyclicality in the data for each pattern that I would like to control for before I add my variables of interest. I run the regression: derp <- tobit(x ~ factor(Month)*factor(County), data = data0, left = 0, right = Inf) If I

Dear All: I need some guidance in calculating a goodness-of-fit statistic for a Tobit Regression model. To develop the Tobit regression, I used the tobit() method from the AER package, which is basically a simpler interface to the survreg() method. I've read about pseudo R2 and C-index and was wondering if there is a package that calculates this for me. Also, is there a reason to select

I've got two brand-new, fully-patched XP SP2 clients who are suffering a mysterious malaise. These two machines will cause a smbd panic when printing or accessing files on a somewhat random basis. Now, the puzzling thing is that three other XP SP2 clients, including one of the exact same configuration, have no issues whatsoever. I've basically ruled out hardware failure on the server,

I need to give a quick description of Tobit Regression (TR), including how it differs from ordinary least squares (OLS). I am an ecologist who knows just enough about remote sensing and statistics to be dangerous in both. Now I have found myself doing a remote sensing project where I have used TR: survreg(Surv()). As far as I can tell, no form of Censored Regression has been used in analyzing

Hi, How can I recover the variance-covariance matrix of the tobit model from the variance-covariance of the survreg? I first used to the survreg function and then I selected the variance matrix. However, the last parameter is log(scale) and not the variance of the standard deviation of the censored distribution as in the Tobit model. tobit<- survreg(Surv(y, y > 0, type ='left')~

Hi, I'm trying to fit a tobit regression model to some data. When fitting the exact same data in Stata, I have no problems at all, however R won't converge. Its not a maxiters thing, since I've tried increasing this already. I need to be able to fit the model in R since there are users of the code that don't have a Stata license. The code is: require(AER) left = 3.218476 x =

Hello R-Users: I am want to use tobit regression for left censored panel/longitudinal data. Could you please provide me the name of "library" and/or "package" that will give me option of fitting tobit regression model for longitudinal data? Thank you. Sattar __________________________________________________ [[alternative HTML version deleted]]

Dear R experts, I am currently working on a rather simple tobit regression, where the dependet variable is left-censored (>0). I would like to apply a Tobit regression and then use the parameters of this regression to make a prediction with new data. The intention behind this is to do an extrapolation. by using the VGAM or AER package, I already succeeded in getting fitted values. However

I'm statistician I need help with tobit regression Is there assumption in tobit regression ? if any, what kind of that ? please help me !!

Folks, Based on http://www.biostat.wustl.edu/archives/html/s-news/1999-06/msg00125.html I thought I should experiment with using survreg() to estimate tobit models. I start by simulating a data frame with 100 observations from a tobit model > x1 <- runif(100) > x2 <- runif(100)*3 > ystar <- 2 + 3*x1 - 4*x2 + rnorm(100)*2 > y <- ystar > censored <- ystar <= 0

Appreciate any suggestions regarding how to fit an unbalanced panel data to a Tobit model using R functions. I am trying to analyze how real estate capital expenditures (CapEx) are affected by market conditions using a panel Tobit model. The CapEx is either positive or 0, so it is censored. The data are unbalanced panel, including the CapEx of about 5000 properties over about 40 quarters, with the

Hi, I am trying to model a score over time. This score shows a ceiling effect. I was willing to use a longitudinal tobit model, such as the one described by Twisk et al. (Twisk_Longitudinal tobit regression: A new approach to analyze outcome variables with floor or ceiling effects_JCE_2009) but it is programmed for STATA. Has anyone used such models in R? Any other idea? David Biau.

Dear Community, does anybody have an idea on how to estimate a system of three seemingly unrelated regressions, two of which being TOBIT and one OLS? Background: I am currently estimating a translog cost function and two corresponding cost share equations using systemfit and the seemingly unrelated regression ("SUR") specification. However, I consider it more appropriate to estimate

Hi all! Do you know if there is any R function/package that can be used to estimate "tobit" models with panel data (e.g. with random individual effects)? In economics, a "tobit" model is a model with a dependent variable that is left-censored at zero. Hence, it is a special case of a survival model and can be estimated using the "survival" package (see e.g.