This paper examines the determinants of export performance of firms in the Greek manufacturing industry, using cross-sectional data from 1652 firms in 1999 and a Tobit regression model. The study finds that firms that have larger size, lower unit labor cost and low capital to labor ratio have a higher propensity to export, confirming the fact that in Greece, which has the second lowest capital ...

In many applications, the response variable is observed only when it is above or below a given threshold otherwise the threshold itself is observed. Tobit median regression model is a useful semiparametric procedure for analyzing this type of censored data. We propose a simple nonparametric test for assessing the common linearity assumption in this model. Compared to those existing methods in t...

Blinder-Oaxaca Decomposition for Tobit Models In this paper, a decomposition method for Tobit-models is derived, which allows the differences in a censored outcome variable between two groups to be decomposed into a part that is explained by differences in observed characteristics and a part attributable to differences in the estimated coefficients. The method is applied to a decomposition of t...

In statistical problems, a set of parameterized probability distributions is used to estimate the true probability distribution. If Fisher information matrix at the true distribution is singular, then it has been left unknown what we can estimate about the true distribution from random samples. In this paper, we study a singular regression problem and prove a limit theorem which shows the relat...

We read with interest the article by Caprioli et al. in the June 2011 issue. In this article, the authors propose a novel method of measuring and predicting the rate of visual field (VF) decay in glaucoma patients. This is an important and clinically relevant topic. Of particular interest was the authors’ application of an exponential fit for threshold sensitivity (in decibels) against time, wh...