Too Connected to Fail? Inferring Network Ties from Price Co-movements
Journal of Business and Economic Statistics,
We use extreme value theory methods to infer conventionally unobservable connections between financial institutions from joint extreme movements in credit default swap spreads and equity returns. Estimated pairwise co-crash probabilities identify significant connections among up to 186 financial institutions prior to the crisis of 2007/2008. Financial institutions that were very central prior to the crisis were more likely to be bailed out during the crisis or receive the status of systemically important institutions. This result remains intact also after controlling for indicators of too-big-to-fail concerns, systemic, systematic, and idiosyncratic risks. Both credit default swap (CDS)-based and equity-based connections are significant predictors of bailouts. Supplementary materials for this article are available online.
The Efficiency of Local Public-service Production: The Effect of Political Institutions
Reforms replacing municipal cooperations by centralized municipalities often aim at increasing municipal efficiency. Empirical evidence supporting this aim, however, is ambiguous. Our paper analyzes the effect of institutions on municipal efficiency. In particular, we distinguish two archetypal institutional settings, a centralized and a confederal one, and argue that bureaucrats in a centralized setting are able to increase the fiscal residual. Our empirical test case is the German federal state of Saxony-Anhalt. We test the effect of the institutional setup using the bootstrap approach suggested by Simar and Wilson (2007), concluding that a decentralized institutional setting improves the efficiency of municipal production.
Tail-risk Protection Trading Strategies
Starting from well-known empirical stylized facts of financial time series, we develop dynamic portfolio protection trading strategies based on econometric methods. As a criterion for riskiness, we consider the evolution of the value-at-risk spread from a GARCH model with normal innovations relative to a GARCH model with generalized innovations. These generalized innovations may for example follow a Student t, a generalized hyperbolic, an alpha-stable or a Generalized Pareto distribution (GPD). Our results indicate that the GPD distribution provides the strongest signals for avoiding tail risks. This is not surprising as the GPD distribution arises as a limit of tail behaviour in extreme value theory and therefore is especially suited to deal with tail risks. Out-of-sample backtests on 11 years of DAX futures data, indicate that the dynamic tail-risk protection strategy effectively reduces the tail risk while outperforming traditional portfolio protection strategies. The results are further validated by calculating the statistical significance of the results obtained using bootstrap methods. A number of robustness tests including application to other assets further underline the effectiveness of the strategy. Finally, by empirically testing for second-order stochastic dominance, we find that risk averse investors would be willing to pay a positive premium to move from a static buy-and-hold investment in the DAX future to the tail-risk protection strategy.
Predicting Financial Crises: The (Statistical) Significance of the Signals Approach
Journal of International Money and Finance,
The signals approach as an early-warning system has been fairly successful in detecting crises, but it has so far failed to gain popularity in the scientific community because it cannot distinguish between randomly achieved in-sample fit and true predictive power. To overcome this obstacle, we test the null hypothesis of no correlation between indicators and crisis probability in three applications of the signals approach to different crisis types. To that end, we propose bootstraps specifically tailored to the characteristics of the respective datasets. We find (1) that previous applications of the signals approach yield economically meaningful results; (2) that composite indicators aggregating information contained in individual indicators add value to the signals approach; and (3) that indicators which are found to be significant in-sample usually perform similarly well out-of-sample.
Size is not everything – The efficiency of municipal service provision in Saxony-Anhalt
Wirtschaft im Wandel,
The proponents of municipal area reforms – e.g. the recently completed reform in Saxony-Anhalt – expect that municipal amalgamations or centralized organizational forms save costs or increase the efficiency of local public service provision. This article examines the potential efficiency deficits of Saxony-Anhalt´s fragmented municipal structures on the eve of the crucial phase of the municipal reform. The results of a two-step DEA bootstrap procedure show that decentralized municipalities (“Verwaltungsgemeinschaften”) do not have to be significantly less efficient than centralized municipalities (“Einheitsgemeinden”). Furthermore, the results of the scale efficiency analysis suggest that the majority of Saxony-Anhalt´s communities already had an approximately efficient “firm size” – if the aggregated level of the municipal associations is examined. The relationship between scale efficiency and population is U-shaped. On the one hand, the results do not support the preservation of micro-municipalities or the formation of municipal associations with more than ten members. On the other hand, the results provide also no evidence for the necessity to reduce the number of towns and municipalities in Saxony-Anhalt from 1118 in 2004 to currently 219 – even if the looming population decline is taken into account.
The Importance of Estimation Uncertainty in a Multi-Rating Class Loan Portfolio
IWH Discussion Papers,
This article seeks to make an assessment of estimation uncertainty in a multi-rating class loan portfolio. Relationships are established between estimation uncertainty and parameters such as probability of default, intra- and inter-rating class correlation, degree of inhomogeneity, number of rating classes used, number of debtors and number of historical periods used for parameter estimations. In addition, by using an exemplary portfolio based on Moody’s ratings, it becomes clear that estimation uncertainty does indeed have an effect on interest rates.