Determining the type of returns to scale (RTS) and identifying stability region for RTS of evaluating unit are appropriate abilities for forecasting the future the unit when its size is changed. This paper aims to introduce RTS sustainability of frontier decision making units (DMUs) in data envelopment analysis (DEA). Based on the importance of RTS in relation to decisions of managers, differen...

data envelopment analysis (dea) is a non-parametric approach for performance analysis of decision making units (dmus) which uses a set of inputs to produce a set of outputs without the need to consider internal operations of each unit. in recent years, there have been various studies dealt with two-stage production systems, i.e. systems which consume some inputs in their first stage to produce ...

in this article, we will estimate efficiency amountof decision-making unit by offering the continuous piecewise polynomialextrapolation and interpolation by ccr model input-oriented on the assumptionthat it is constant returns to scale in different times. and finally, we willestimate efficiency amount of decision-making unit indifferent times byoffering an example.

sueyoshi and sekitani in 2007 presented a paper that explores the measurement of returns to scale under a possible occurrence of multiple solution in a reference set and a supporting hyperplane. the occurrence ofmultiple solutions is classified into type i and type ii. type i is an occurrence of multiple solutions in a reference set. type ii is an occurrence of multiple solutions on a supportin...

the measurement of rts amounts measures a relationship between inputs and outputs in a production structure. there are many different ways to calculate rts in primal or dual space. but in more realistic cases, governments usually intervene on dmu’s behavior as regulatory agency, this clearly represent a set of limitations and restrictions on behaviors of dmus, so very few decisions in dmus are ...

the basic models of data envelopment analysis (dea) are designed in such a way that the values of input and output indicators should be identified and known in them. in other words, these models are not used to consider inaccurate, interval, fuzzy, judgment data. in this paper, the aim is to not only review the past researches about the efficiency of the units by interval data and represent the...