Automated lip reading from videos requires segmentation. Threshold-based segmentation is straightforward, but it rarely used. This study proposes a histogram threshold based on the feedback of shape information. Both good and bad examples were used to train an $$\epsilon $$ -support vector regression model infer accuracy region shape. The was optimised minimise error. proposed method tested 895...

in the present study, air quality analyses for ozone (o3) were conducted in shiraz, a city in the south of iran. the measurements were taken from 2011 through 2012 in two different locations to prepare average data in the city. the average concentrations were calculated for every 24 hours, each month and each season. results showed that the highest concentration of ozone occurs generally in the...

This paper studies control function (CF) approaches in endogenous threshold regression where the variable is allowed to be endogenous. We first use a simple example show that structural (STR) estimator of point Kourtellos, Stengos and Tan (2016, Econometric Theory 32, 827–860) inconsistent unless endogeneity level low compared effect. correct CF STR generate our using method extends two-stage l...

In regression discontinuity models, where the probability of treatment jumps discretely when a running variable crosses a threshold, an average treatment effect can be nonparametrically identi ed. We show that the derivative of this treatment effect with respect to the threshold is also nonparametrically identi ed and easily estimated, in both sharp and fuzzy designs. This marginal threshold tr...

In this article, we develop a general method for testing threshold effects in regression models, using sup-likelihood-ratio (LR)-type statistics. Although the sup-LR-type test statistic has been considered in the literature, our method for establishing the asymptotic null distribution is new and nonstandard. The standard approach in the literature for obtaining the asymptotic null distribution ...