This paper discusses the determination of returns to scale (RTS) in data envelopment analysis (DEA). Three basic RTS methods and their modi®cations are reviewed and the equivalence between these di€erent RTS methods is presented. The e€ect of multiple optimal DEA solutions on the RTS estimation is studied. It is shown that possible alternate optimal solutions only a€ect the estimation of RTS on...

Influence maximization is a problem of maximizing the aggregate adoption of products, technologies, or even beliefs. Most past algorithms leveraged an assumption of submodularity that captures diminishing returns to scale. While submodularity is natural in many domains, early stages of innovation adoption are often better characterized by convexity, which is evident for renewable technologies, ...

Traditional super-efficiency data envelopment analysis (DEA) models rank efficient units under the assumption of constant returns to scale (CRS). However, infeasibility may occur in super-efficiency models under variable returns to scale (VRS). This paper proposes a modified VRS super-efficiency DEA model to deal with infeasibility by relaxing the convexity constraint 1, 0 1 n j j j λ = ≠ = ∑ t...

Differences between the concepts of returns to size and returns to scale are systematically reexamined in this paper. Specifically, the relationship between returns to scale and size are examined through the use of the envelope theorem. A major conclusion of the paper is that the level of abstraction in applying a cost function derived from a homothetic technology within a relevant range of the...

BACKGROUND The objectives of the present study are to investigate the efficacy and safety profile of gemcitabine-based combinations in the treatment of locally advanced and metastatic pancreatic adenocarcinoma (LA/MPC). METHODS We performed a computerized search using combinations of the following keywords: "chemotherapy", "gemcitabine", "trial", and "pancreatic cancer". RESULTS Thirty-five...

This note generalizes analytical relationships among activity variables of DEA models previously derived by Boussemart, Briec and Leleu (2007). We relax the asumption of constant returns to scale by showing that the key results hold under a weaker asumption of homogeneity. We use the notion of α -returns to scale to extend the analysis to strictly increasing and decreasing returns, covering now...

Examination of the relation between scale economies and natural monopoly has been a central issue in public policy research. The paper employs Data Envelopment Analysis (DEA) methodology to re-examine the issue of natural monopoly for the Bell system with annual time series data for 1947–1977. Results from the DEA-based statistical tests reveal the prevalence of increasing returns to scale for ...

We consider a Cournot Oligopoly market of firms possessing increasing returns to scale technologies (which may not be identical). It is shown that an external regulating agency can increase total social welfare without running a deficit by offering to subsidize one firm an amount which depends on the output level of that firm and the market price. The firms bid for this contract, the regulator ...

The goal of an individual searching for a marriage partner is typically to form a long-term relationship. Marital search is a complicated and costly activity, where opportunities typically arrive over time at uncertain intervals, each party has to evaluate each other’s characteristics, and expectations play an important role. Given these features of marital search, a seminal paper by Mortensen ...