@article{NeumannNieswandSchubert2016,
  author    = {Neumann, Anne and Nieswand, Maria and Schubert, Torben},
  title     = {Estimating alternative technology sets in nonparametric efficiency analysis: restriction tests for panel and clustered data},
  series = {Journal of productivity analysis},
  volume    = {45},
  journal   = {Journal of productivity analysis},
  publisher = {Springer},
  address   = {Dordrecht},
  issn      = {0895-562X},
  doi       = {10.1007/s11123-015-0461-z},
  pages     = {35 -- 51},
  year      = {2016},
  abstract  = {Nonparametric efficiency analysis has become a widely applied technique to support industrial bench-marking as well as a variety of incentive-based regulation policies. In practice such exercises are often plagued by incomplete knowledge about the correct specifications of inputs and outputs. Simar and Wilson (Commun Stat Simul Comput 30(1): 159-184, 2001) and Schubert and Simar (J Prod Anal 36(1): 55-69, 2011) propose restriction tests to support such specification decisions for cross-section data. However, the typical oligopolized market structure pertinent to regulation contexts often leads to low numbers of cross-section observations, rendering reliable estimation based on these tests practically unfeasible. This small-sample problem could often be avoided with the use of panel data, which would in any case require an extension of the cross-section restriction tests to handle panel data. In this paper we derive these tests. We prove the consistency of the proposed method and apply it to a sample of US natural gas transmission companies from 2003 through 2007. We find that the total quantity of natural gas delivered and natural gas delivered in peak periods measure essentially the same output. Therefore only one needs to be included. We also show that the length of mains as a measure of transportation service is non-redundant and therefore must be included.},
  language  = {en}
}
@article{NeumannRosellonWeigt2015,
  author    = {Neumann, Anne and Rosellon, Juan and Weigt, Hannes},
  title     = {Removing Cross-Border Capacity Bottlenecks in the European Natural Gas Market-A Proposed Merchant-Regulatory Mechanism},
  series = {Networks and spatial economics : a journal of infrastructure modeling and computation},
  volume    = {15},
  journal   = {Networks and spatial economics : a journal of infrastructure modeling and computation},
  number    = {1},
  publisher = {Springer},
  address   = {Dordrecht},
  issn      = {1566-113X},
  doi       = {10.1007/s11067-014-9273-3},
  pages     = {149 -- 181},
  year      = {2015},
  abstract  = {We propose a merchant-regulatory framework to promote investment in the European natural gas network infrastructure based on a price cap over two-part tariffs. As suggested by Vogelsang (J Regul Econ 20:141-165, 2001) and Hogan et al. (J Regul Econ 38:113-143, 2010), a profit maximizing network operator facing this regulatory constraint will intertemporally rebalance the variable and fixed part of its two-part tariff so as to expand the congested pipelines, and converge to the Ramsey-Boiteaux equilibrium. We confirm this with actual data from the European natural gas market by comparing the bi-level price-cap model with different reference cases. We analyze the performance of the regulatory approach under different market scenarios, and identify relevant aspects that need to be addressed if the approach were to be implemented.},
  language  = {en}
}
@article{NeumannvonHirschhausen2015,
  author    = {Neumann, Anne and von Hirschhausen, Christian},
  title     = {Natural Gas: An Overview of a Lower-Carbon Transformation Fuel},
  series = {Review of environmental economics and policy},
  volume    = {9},
  journal   = {Review of environmental economics and policy},
  number    = {1},
  publisher = {Oxford Univ. Press},
  address   = {Oxford},
  issn      = {1750-6816},
  doi       = {10.1093/reep/reu022},
  pages     = {64 -- 84},
  year      = {2015},
  abstract  = {This article provides an overview of the natural gas industry, which we view as a bridge fuel toward a lower-carbon energy system in many countries and regions around the world. Based on a review of the literature, an econometric analysis of natural gas prices and contracts, and the authors' experience with the natural gas industry, this introductory article to the symposium on the Prospects for Natural Gas in a Lower-Carbon Context provides an overview of research on natural gas markets over the last decade and examines various features of the natural gas industry, including its technical structure, activities in the value-added chain, trade and market trends, short- and long-term price developments, and the geopolitical landscape. More specifically, we describe the natural gas sector and provide an overview of production, reserves, and consumption. We also examine the evolution of long-term contracts between producers and large-scale buyers of natural gas and present some recent empirical evidence. Finally, we discuss the changing geopolitics of natural gas, focusing in particular on the future roles of the United States as a potential natural gas exporter and Asia as the major importing region. (JEL: L11, L95, Q49).},
  language  = {en}
}
@article{ZaklanAbrellNeumann2016,
  author    = {Zaklan, Aleksandar and Abrell, Jan and Neumann, Anne},
  title     = {Stationarity changes in long-run energy commodity prices},
  series = {Energy economics},
  volume    = {59},
  journal   = {Energy economics},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0140-9883},
  doi       = {10.1016/j.eneco.2016.07.022},
  pages     = {96 -- 103},
  year      = {2016},
  abstract  = {Situated at the intersection of the literatures on speculative storage and non-renewable commodity scarcity, this paper considers whether changes in persistence have occurred in long-run U.S. prices of the energy commodities crude oil, natural gas and bituminous coal. We allow for a structural break when testing for a break in persistence to avoid a change in the stochastic properties of prices being confounded by an unaccounted-for deterministic shift in the price series. We find that coal prices are trend stationary throughout their evolution and that oil prices change from stationarity to non-stationarity in the decade between the late 1960s to late 1970s. The result on gas prices is ambiguous. Our results demonstrate the importance of accounting for a possible structural shift when testing for breaks in persistence, while being robust to the exact date of the structural break. Based on our analysis we caution against viewing long-run energy commodity prices as being non-stationary and conclude in favor of modeling commodity market fundamentals as stationary, meaning that speculative storage will tend to have a dampening effect on prices. We also cannot reject that long-run prices of coal and, with some hesitation, gas follow a Hotelling-type rule. In contrast, we reject the Hotelling rule for oil prices since the late 1960s/early 1970s. (C) 2016 Elsevier B.V. All rights reserved.},
  language  = {en}
}
@article{ZaklanCullmannNeumannetal.2012,
  author    = {Zaklan, Aleksandar and Cullmann, Astrid and Neumann, Anne and von Hirschhausen, Christian},
  title     = {The globalization of steam coal markets and the role of logistics an empirical analysis},
  series = {Energy economics},
  volume    = {34},
  journal   = {Energy economics},
  number    = {1},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0140-9883},
  doi       = {10.1016/j.eneco.2011.03.001},
  pages     = {105 -- 116},
  year      = {2012},
  abstract  = {In this paper, we provide a comprehensive multivariate cointegration analysis of three parts of the steam coal value chain - export, transport and import prices. The analysis is based on a rich dataset of international coal prices: in particular, we combine data on steam coal prices with freight rates, covering the period December 2001 until August 2009 at weekly frequency. We then test whether the demand and supply side components of steam coal trade are consistently integrated with one another. In addition, export and import prices as well as freight rates for individual trading routes, across regions and globally are combined. We find evidence of significant yet incomplete integration. We also find heterogeneous short-term dynamics of individual markets. Furthermore, we examine whether logistics enter coal price dynamics through transportation costs, which are mainly determined by oil prices. Our results suggest that this is generally not the case.},
  language  = {en}
}