The aim of this paper is to use the concept of the metafrontier function to study the determination of efficiency differentials and Technological Gap Ratio (TGR) on wheat production in Khorasan Razavi province. In this study, we used the metafrontier function and group frontier based on the concept of Stochastic Nonparametric Envelopment of Data analysis (StoNED). The data used in this stud...

four hundered and ninety five (495) smallholder dairy farms active in 52 villages of different cities in chaharmohalo bakhtiari province, keeping 1321 lactating within a total of 2811 mature cows (lactating and dry) were used. these herds were taken during winter 2009 to summer 2010 to assess some of the production, reproductive and economic performance traits under smallholder management syste...

state in the country with more than 1.5 million This study evaluates the economic suracres (USDA, Crop Production). vivability of rice farms in the Delta area of Since 1981, rice acreage in the Mississippi Mississippi. A general whole-farm simulation River Delta region, as in other rice-producing model, FLIPSIM V, is used to simulate the regions of the country, has generally declined. operation...

One of the most important subjects in relation of water resources quality in the many of river is the chemical composition of waters and conservation of water quality in the watershed. Geological formations in any region of the earth are the main surface and foundation that water flows on the bed and strata of formation, which in fact they affect their characteristics on water quality as positi...

the aim of this paper is to use the concept of the metafrontier function to study the determination of efficiency differentials and technological gap ratio (tgr) on wheat production in khorasan razavi province. in this study, we used the metafrontier function and group frontier based on the concept of stochastic nonparametric envelopment of data analysis (stoned). the data used in this study co...

trend towards farm consolidation, it is also imThe purpose of this paper is to measure the portant to know if large farms are more techextent of technical inefficiency among a nically efficient than smaller ones. Finally, it sample of Illinois grain farms using the corshould be noted that the method developed rected ordinary least squares method. Instead here can be easily applied to farm data ...

I prove that there is a recursive function T that does the following: Let X be transitive and rud closed, and let X ′ be the closure of X ∪{X} under rud functions. Given a Σ0 formula φ(x) and a code c for a rud function f , T (φ, c, ~x) is a Σω formula such that for any ~a ∈ X, X ′ |= φ[f(~a)] iff X |= T (φ, c, ~x)[~a]. I make this precise and show relativized versions of this. As an applicatio...

While some research finds that environmental regulation of hog production reduces output by small farms, other work finds that large farms downsize to avoid regulation. None consider the potential size-bias of regulation. We show theoretically that when size-based regulations are also size-biased, large farms downsize, expand, or do neither depending on how regulations shift their marginal prod...

Purpose The aim of this study was to assess phosphorusretention (Pret) capacities via P adsorption (Pads) and desorption (Pdes) by sediments collected from six different sources associated with various origins, physical, and chemical characteristics. Materials and methods Sediment samples were collected in the State of Florida, the USA, from estuary, marine, wetland, canal, river, and lake, res...