Axiomatic Foundations of Efficiency Measurement on Data-Generated Technologies

Dmitruk and Koshevoy [1991 JET] provided a complete characterization of the class of technologies for which there exists an efficiency index satisfying the Fare-Lovell [1978 JET] axioms. The technologies implicit in the standard mathematical-programming methods of measuring efficiency, data envelopment analysis (DEA) and free-disposal-hull (FDH) analysis, belong to this class. We assess the ability of three well-known indexes, the Debreu-Farrell index, the Fare-Lovell index, and the Zieschang index, to satisfy not only the Fare-Lovell axioms but also continuity axioms (for technologies as well as input quantities), on this restricted class of technologies. Our principal conclusions are that (a) restriction to these data-based technologies adds continuity in input quantities to the properties satisfied by the Fare-Lovell and the Zieschang indexes (thus eliminating a salient advantage of the Debreu-Farrell index), but (b) none of the indexes satisfies all Fare-Lovell axioms (nor all continuity axioms) on either DEA or FDH technologies, and hence (c) trade-offs among the indexes remain. These findings provide motivation for the search for an index that does satisfy these axioms on DEA and FDH technologies.Technical efficiency indexes; technical efficiency axioms

Theoretical macroeconomic modelling and qualitative specifications of the bond market

Macroeconomics ; Bonds

A cross-sectional study of predatory publishing emails received by career development grant awardees

OBJECTIVE: To investigate the scope of academic spam emails (ASEs) among career development grant awardees and the factors associated with the amount of time spent addressing them. DESIGN: A cross-sectional survey of career development grant investigators via an anonymous online survey was conducted. In addition to demographic and professional information, we asked investigators to report the number of ASEs received each day, how they determined whether these emails were spam and time they spent per day addressing them. We used bivariate analysis to assess factors associated with the amount of time spent on ASEs. SETTING: An online survey sent via email on three separate occasions between November and December 2016. PARTICIPANTS: All National Institutes of Health career development awardees funded in the 2015 fiscal year. MAIN OUTCOME MEASURES: Factors associated with the amount of time spent addressing ASEs. RESULTS: A total of 3492 surveys were emailed, of which 206 (5.9%) were returned as undeliverable and 96 (2.7%) reported an out-of-office message; our overall response rate was 22.3% (n=733). All respondents reported receiving ASEs, with the majority (54.4%) receiving between 1 and 10 per day and spending between 1 and 10 min each day evaluating them. The amount of time respondents reported spending on ASEs was associated with the number of peer-reviewed journal articles authored (p<0.001), a history of publishing in open access format (p<0.01), the total number of ASEs received (p<0.001) and a feeling of having missed opportunities due to ignoring these emails (p=0.04). CONCLUSIONS: ASEs are a common distraction for career development grantees that may impact faculty productivity. There is an urgent need to mitigate this growing problem