Replik zu den Erwiderungen zu den Anmerkungen zu den Determinanten der Pr��fungshonorare in Deutschland

I maintain my critique of the studies of Bigus and Zimmermann (2009) and of Köhler et al. (2010) without reservation. In light of the legal basis of the scope of audits of financial statements, of auditing standards, of the practice of auditing of international groups of companies, and of international studies of audit fees, the replies of the authors do not provide solid counter arguments and do not seem to take the practice of auditing into account.     

Dependency of Crop Production between Global Breadbaskets: A Copula Approach for the Assessment of Global and Regional Risk Pools

As recent events have shown, simultaneous crop losses in different parts of the world can cause serious risks to global food security. However, to date, little is known about the spatial dependency of lower than expected crop yields from global breadbaskets. This especially applies in the case of extreme events, i.e., where one or more breadbaskets are experiencing far below average yields. Without such information, risk management approaches cannot be applied and vulnerability to extremes may remain high or even increase in the future around the world. We tackle both issues from an empirical perspective focusing on wheat yield. Interdependencies between historically observed wheat yield deviations in five breadbaskets (United States, Argentina, India, China, and Australia) are estimated via copula approaches that can incorporate increasing tail dependencies. In doing so, we are able to attach probabilities to interregional as well as global yield losses. To address the robustness of our results, we apply three different methods for constructing multivariate copulas: vine copulas, ordered coupling using a minimax approach, and hierarchical structuring. We found interdependencies between states within breadbaskets that led us to the conclusion that risk pooling for extremes is less favorable on the regional level. However, notwithstanding evidence of global climatic teleconnections that may influence crop production, we also demonstrate empirically that wheat production losses are independent between global breadbaskets, which strengthens the case for interregional risk pooling strategies. We argue that through interregional risk pooling, postdisaster liabilities of governments and international donors could be decreased.     

Asymptotically optimal rank tests for the two-sample problem with randomly censored data

Using the methods of asymptotic decision theory asymptotically optimal rank tests are constructed in the two-sample testing problem for translation families and positive scale families under the assumption of equal censoring in both samples. The resulting tests have a simple form extending the known tests for un-censored data in a natural way. Relations to a recent proposal by Albers and Akritas are discussed.     

DOES RELATIONSHIP SPECIFIC INVESTMENT DEPEND ON ASSET OWNERSHIP? EVIDENCE FROM A NATURAL EXPERIMENT IN THE HOUSING MARKET

In this paper, I test the most basic prediction of Grossman and Hart (1986, The Costs and Benefits of Ownership: A Theory of Vertical and Lateral Integration. Journal of Political Economy, 691–719): allocations of asset ownership that expose a party to ex‐post expropriation reduce this party’s ex‐ante relationship‐specific investments. In the empirical context of the German housing market, I find that relationship‐specific investments, such as bathroom renovations, are more frequent if the occupant is protected against expropriation because he owns his home. To avoid the endogeneity of the homeownership allocation, I rely on the natural experiment of the German reunification: under the communist regime, ownership existed but was economically meaningless; yet after reunification, ownership unexpectedly reacquired legal force.     

The irreversibility effect and agency conflicts

This paper studies the influence of agency conflicts on the irreversibility effect. Using a dynamic variant of the static Baron and Myerson (Econometrica 50(4):911–930, 1982) adverse selection model, we characterize under which circumstances the irreversibility effect arises in the presence and absence of an agency conflict. In particular, we find that in the presence of an agency conflict the irreversibility effect arises in more circumstances than in the standard first-best analysis that abstracts from agency problems.