All of the Department Discussion Papers are submitted to RePEc. The EconPapers or IDEAS sites allow you to search by author, title, keyword, JEL category and abstract contents.
Papers from 1998 onwards are available on-line as .PDF files.
14/19 Stephen G. Hall, P. A. V. B. Swamy, George S. Tavlas
The method of instrumental variables (IV) and the generalized method of moments (GMM), and their applications to the estimation of errors-in-variables and simultaneous equations models in econometrics, require data on a sufficient number of instrumental variables that are both exogenous and relevant. We argue that, in general, such instruments (weak or strong) cannot exist.
14/18 Stephen G. Hall, P. A. V. B. Swamy, George S. Tavlas
14/17 Heather D. Gibson, Stephen G. Hall and George S.Tavlas
We quantify the linkages among banks’ equity performance and indicators of sovereign stress by using panel GMM to estimate a three-equation system that examines the impact of sovereign stress, as reflected in both sovereign spreads and sovereign ratings, on bank share prices. We use data for a panel of five euro-area stressed countries. Our findings indicate that a long-run recursive relationship between sovereigns and banks operated during the euro-area crisis. Specifically, for the five crisis countries considered shocks to sovereign spreads fed-through to sovereign ratings, which affected commercial banks. Our results also point to the importance of using levels of equity prices -- rather than rates of return -- in measuring banks’ performance. The use of levels allows us to derive the determinants of long-run equity prices.
14/16 Heather D. Gibson, Stephen G. Hall and George S.Tavlas
During the euro-area financial crisis, interactions between sovereign spreads and credit ratings appeared to have led to self-generating feedback loops. To examine the interaction between spreads and ratings, we estimate a simultaneous two-equation model in which spreads and ratings are endogenous. Using a panel of 5 euro-area countries, we construct time series comprising the ratings of its sovereigns determined by the three major rating agencies. We find that, controlling for the economic and political fundamentals, spreads and ratings strongly interacted with each other during the crisis, producing effects well-beyond those of the fundamentals, and with the interactions demonstrating high persistence.
14/15 Maria Jose Gil-Molto and Dimitrios Varvarigos
We compare economic and environmental outcomes under mixed and private oligopolies, in order to examine the effects of privatization when firms invest in abatement and emissions are taxed. We show that the number of competing firms in the market is an important factor in the determination of these effects. While privatization often involves a welfare trade-off, in the sense that higher (lower) output production implies higher (lower) pollution, there are also circumstances where it leads to both lower output and higher emissions simultaneously. Our results also indicate that privatization tends be associated with reductions in social welfare.
14/14 Svetlana Adrianova, Badi H. Baltagi, Panicos Demetriades and David Fielding
We present a theoretical model of moral hazard and adverse selection in an imperfectly competitive loans market that is suitable for application to Africa. The model allows for variation in both the level of contract enforcement (depending on the quality of governance) and the degree of market segmentation (depending on the level of ethnic fractionalization). The model predicts a specific form of non-linearity in the effects of these variables on the loan default rate. Empirical analysis using African panel data for 111 individual banks in 29 countries over 2000-2008 provides strong evidence for these predictions. Our results have important implications for the conditions under which policy reform will enhance financial development.
14/13 Sergio Currarini, Elena Fumagalli and Fabrizio Panebianco
We study linear quadratic games played on a network where strategies are complements between neighbors and substitutes between agents at distance-two. We provide micro-founded problems where this pattern of interaction is due to a local congestion effect. Equilibrium behavior systematically differs from a model of peer effects only. First, the ranking of equilibrium actions may not follow that of network centralities, with large behavior prevailing at the periphery of the network. Second, network density affects aggregate behavior in a non-monotonic way. Third, segregating agents according to their preferences has a non-monotonic effect on the polarization of behavior. We relate these patterns to evidence from smoking networks, industrial districts and ethnically fragmented societies. We conclude by discussing the implications for the identification of peer effects.
14/12 Subir Bose and Arup Daripa
Online auctions with a fixed end-time often experience a sharp increase in bidding towards the end despite using a proxy-bidding format. We provide a novel explanation of this phenomenon under private values. We study a correlated private values environment in which the seller bids in her own auction (shill bidding). Bidders selected randomly from some large set arrive randomly in an auction, then decide when to bid (possibly multiple times) over a continuous time interval. A submitted bid arrives over a continuous time interval according to some stochastic distribution. The auction is a continuous-time game where the set of players is not commonly known, a natural setting for online auctions. Our results are robust with respect to the seller’s and the bidders’ priors regarding the set of bidders arriving at the auction. We show that there is a late-bidding equilibrium in which bids are delayed to the latest instance involving no sacrifice of probability of bid arrival, but shill bids fail to arrive with positive probability, and in this sense optimal late bidding serves to snipe the shill bids. We show conditions under which the equilibrium outcome is unique. Further, if these conditions do not hold, and there are any equilibria with a different outcome, they are necessarily characterized by early bidding. Any such equilibria are Pareto dominated for the bidders compared to the late-bidding equilibrium. Finally, our results suggest that under private values, the case against shill-bidding might be weak.
14/11 Ali al-Nowaihi and Sanjit Dhami
A critical element in all discounted utility models is the specification of a discount function. We introduce three functions: the delay, speedup and generating functions. Each can be uniquely elicited from behaviour. The delay function determines stationary and the common difference effect. The speedup function determines impatience. Additivity is jointly determined by the delay and speedup functions. The speedup and generating functions jointly determine a unique discount function. Conversely, a continuous discount function determines unique speedup and generating functions.
14/10 Eleni Stathopoulou
In an international duopoly context, where two goods are produced by two firms located in two separate countries, F and NF, we study the issue of firms' environmental technology choice. When consumers in country F are environmentally aware, in the sense that they care about emissions in their own country, it is shown that the firm in country F adopts a cleaner technology compared to the firm in country NF. Moreover, leakage appears, as the demand by consumers in country F shifts to the good produced by the firm in country NF. This, in turn, provides a rationale for raising awareness among consumers in country F about the effects of their consumption on pollution in country NF. Thereby, this paper adds to the existing literature by analysing how this increased awareness may affect consumers' demand for the domestic and the foreign good and, therefore,firms' endogenous technology choice. Also, changes in each country's and aggregate pollution are examined in order to assess whether having domestic consumers aware of foreign emissions could be considered as an option for tackling leakage.