Missing data is one of the most common challenges facing empirical researchers. This paper presents a general GMM framework for dealing with missing data on explanatory variables or instrumental variables. For a linear-regression model with missing covariate data, an efficient GMM estimator under minimal assumptions on missingness is proposed. The estimator, which also allows for a specificatio...

We consider the problem of classifying a test sample given incomplete information. This problem arises naturally when data about a test sample is collected over time, or when costs must be incurred to compute the classification features. For example, in a distributed sensor network only a fraction of the sensors may have reported measurements at a certain time, and additional time, power, and b...

Correspondence *Corresponding author Email: [email protected] Presence of missing values in a dataset can adversely affect the performance of a classifier; it deteriorates rapidly as missingness increases. Single and Multiple Imputation (MI) are normally performed to fill in the missing values. In this paper, we present several variants of combining MI and bootstrapping to create ensembl...

policy making and planning for agricultural development and conditional improvement of rural and farmers requires accurate and real time information and statistics. in iran, accessing relevant agriculture statistics is mainly gained through expert knowledge and traditional methods. studies show that these have a high percent of error. this research has been aimed so to, by using new methods inc...

A large part of sensor, image, and statistics data in the Earth Sciences naturally come as data points aligned to regular grids of some dimension, including 1-D time series, 2-D imagery, 3-D image time series and volumetric data, and 4-D spatio-temporal data. Frequently repositories have to host objects of multi-Terabyte size, in the future multi-Petabytes. Serving this information category, la...

ÐGiven a three-dimensional numerical geological model it is often useful to determine the geological modeling cells that are connected in three dimensions. These connected three-dimensional bodies are referred to as geo-objects; a program geo_obj is presented to calculate the geo-objects from three-dimensional lithofacies, porosity and permeability models. Relevant summary statistics such as th...

from the perspective of the states that their foreign policy is based on geo-economy, the economy is the most important mechanism of influence in target areas. therefore, with the strengthening of trade relations would be in an appropriate level to increase the mutual relations.  after the independence of central eurasian states, geographical - political events of central eurasia led to the cre...