Advancements in data collection techniques and the heterogeneity of resources can yield high percentages missing observations on variables, such as block-wise data. Under missing-data scenarios, traditional methods simple average, k-nearest neighbor, multiple, regression imputations may lead to results that are unstable or unable be computed. Motivated by concept semi-supervised learning, we pr...

This draft chapter, prepared for inclusion in the (prospective) Handbook of Production Economics, Vol. 1 (Theory), edited by Subash Ray, Robert Chambers, and Subal Kumbhakar, analyses recent developments in the modeling of pollution-generating technologies. We first lay out the inadequacies of the traditional, single-equation representations of models of such technologies prominently associated...

In this paper, we focus on a class of dual-rate sampled-data systems in which all the inputs u(t) are available at each instant while only scarce outputs y(qt) can be measured (q being an integer more than unity). To estimate the parameters of such dual-rate systems, we derive amathematicalmodel by using the polynomial transformation technique, and apply the extended least squares algorithm to ...

(2011). Investigation of peatland restoration (grip blocking) techniques to achieve best outcomes for methane and greenhouse gas emissions/balance. Copyright and Moral Rights for the articles on this site are retained by the individual authors and/or other copyright owners. For more information on Open Research Online's data policy on reuse of materials please consult the policies page.

a case of multiple pulp stones, a supernumerary tooth and a congenitally missed tooth accompanied by several developmental dental anomalies concurrently affect- ing the upper and lower anterior teeth in an iranian healthy girl is reported. devel- opmental tooth abnormalities are usually found in conjunction with certain diseases or conditions. in the present case, although the patient had consa...

statement of the problem replacement of missing or lost teeth with dental prostheses supported by dental implants has been accepted and received positive evaluations from patients who have undergone implant treatment. purpose the aim of this study was to evaluate the level of patient knowledge about dental implants among a selected sample of dental patients in tabriz, iran materials and methods...

background policy makers need models to be able to detect groups at high risk of hiv infection. incomplete records and dirty data are frequently seen in national data sets. presence of missing data challenges the practice of model development. several studies suggested that performance of imputation methods is acceptable when missing rate is moderate. one of the issues which was of less concern...

T he notion that the distribution of firm size in poor countries is characterized by a bimodal distribution with a “missing middle” is a widely accepted fact in development economics (for example, see Krueger 2013). The idea of the missing middle is that there are a large number of small firms, some large firms, but very few medium-sized firms. The purported fact about the missing middle is cit...