OPUS 4 | Universitätspublikationen

Selected Results from Socio-Ecological Participatory Situation Assessments in Two Sites in Central Northern Namibia (2008)

Jutta Deffner Patrik Klintenberg Clarence Mazambani Petra Moser-Norgaard Nantanga Komeine Mary Seely

Village-scale and Solar Desalination Technology Experience in Namibia (2008)

Detlof von Oertzen Robert Schultz

The Global Crop Water Model (GCWM) : documentation and first results for irrigated crops (2008)

Stefan Siebert Petra Döll

A new global crop water model was developed to compute blue (irrigation) water requirements and crop evapotranspiration from green (precipitation) water at a spatial resolution of 5 arc minutes by 5 arc minutes for 26 different crop classes. The model is based on soil water balances performed for each crop and each grid cell. For the first time a new global data set was applied consisting of monthly growing areas of irrigated crops and related cropping calendars. Crop water use was computed for irrigated land and the period 1998 – 2002. In this documentation report the data sets used as model input and methods used in the model calculations are described, followed by a presentation of the first results for blue and green water use at the global scale, for countries and specific crops. Additionally the simulated seasonal distribution of water use on irrigated land is presented. The computed model results are compared to census based statistical information on irrigation water use and to results of another crop water model developed at FAO.

Global dataset of monthly growing areas of 26 irrigated crops : version 1.0 (2008)

Felix Theodor Portmann Stefan Siebert Christian Bauer Petra Döll

A data set of monthly growing areas of 26 irrigated crops (MGAG-I) and related crop calendars (CC-I) was compiled for 402 spatial entities. The selection of the crops consisted of all major food crops including regionally important ones (wheat, rice, maize, barley, rye, millet, sorghum, soybeans, sunflower, potatoes, cassava, sugar cane, sugar beets, oil palm, rapeseed/canola, groundnuts/peanuts, pulses, citrus, date palm, grapes/vine, cocoa, coffee), major water-consuming crops (cotton), and unspecified other crops (other perennial crops, other annual crops, managed grassland). The data set refers to the time period 1998-2002 and has a spatial resolution of 5 arc minutes by 5 arc minutes which is 8 km by 8 km at the equator. This is the first time that a data set of cell-specific irrigated growing areas of irrigated crops with this spatial resolution was created. The data set is consistent to the irrigated area and water use statistics of the AQUASTAT programme of the Food and Agriculture Organization of the United Nations (FAO) (http://www.fao.org/ag/agl/aglw/aquastat/main/index.stm) and the Global Map of Irrigation Areas (GMIA) (http://www.fao.org/ag/agl/aglw/aquastat/irrigationmap/index.stm). At the cell-level it was tried to maximise consistency to the cropland extent and cropland harvested area from the Department of Geography and Earth System Science Program of the McGill University at Montreal, Quebec, Canada and the Center for Sustainability and the Global Environment (SAGE) of the University of Wisconsin at Madison, USA (http://www.geog.mcgill.ca/~nramankutty/ Datasets/Datasets.html and http://geomatics.geog.mcgill.ca/~navin/pub/Data/175crops2000/). The consistency between the grid product and the input data was quantified. MGAG-I and CC-I are fully consistent to each other on entity level. For input data other than CC-I, the consistency of MGAG-I on cell level was calculated. The consistency of MGAG-I with respect to the area equipped for irrigation (AEI) of GMIA and to the cropland extent of SAGE was characterised by the sum of the cell-specific maximum difference between the MGAG-I monthly total irrigated area and the reference area when the latter was exceeded in the grid cell. The consistency of the harvested area contained in MGAG-I with respect to SAGE harvested area was characterised by the crop-specific sum of the cell-specific difference between MGAG-I harvested area and the SAGE harvested area when the latter was exceeded in the grid cell. In all three cases, the sums are the excess areas that should not have been distributed under the assumption that the input data were correct. Globally, this cell-level excess of MGAG-I as compared to AEI is 331,304 ha or only about 0.12 % of the global AEI of 278.9 Mha found in the original grid. The respective cell-level excess of MGAG-I as compared to the SAGE cropland extent is 32.2 Mha, corresponding to about 2.2 % of the total cropland area. The respective cell-level excess of MGAG-I as compared to the SAGE harvested area is 27 % of the irrigated harvested area, or 11.5 % of the AEI. In a further step that will be published later also rainfed areas were compiled in order to form the Global data set of monthly irrigated and rainfed crop areas around the year 2000 (MIRCA2000). The data set can be used for global and continental-scale studies on food security and water use. In the future, it will be improved, e.g. with a better spatial resolution of crop calendars and an improved crop distribution algorithm. The MIRCA2000 data set, its full documentation together with future updates will be freely available through the following long-term internet site: http://www.geo.uni-frankfurt.de/ipg/ag/dl/forschung/MIRCA/index.html. The research presented here was funded by the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) within the framework of the research project entitled "Consistent assessment of global green, blue and virtual water fluxes in the context of food production: regional stresses and worldwide teleconnections". The authors thank Navin Ramankutty and Chad Monfreda for making available the current SAGE datasets on cropland extent (Ramankutty et al., 2008) and harvested area (Monfreda et al., 2008) prior to their publication.

Financial locations : Frankfurt’s place and perspectives (2008)

Hans-Helmut Kotz Reinhard H. Schmidt

The introduction of a common currency as well as the harmonization of rules and regulations in Europe has significantly reduced distance in all its guises. With reduced costs of overcoming space, this emphasizes centripetal forces and it should foster consolidation of financial activity. In a national context, as a rule, this led to the emergence of one financial center. Hence, Europeanization of financial and monetary affairs could foretell the relegation of some European financial hubs such as Frankfurt and Paris to third-rank status. Frankfurt’s financial history is interesting insofar as it has lost (in the 1870s) and regained (mainly in the 1980s) its preeminent place in the German context. Because Europe is still characterized by local pockets of information-sensitive assets as well as a demand for variety the national analogy probably does not hold. There is room in Europe for a number of financial hubs of an international dimension, including Frankfurt.

A partially linear approach to modelling the dynamics of spot and futures prices (2008)

Jürgen Gaul Erik Theissen

In this paper we consider the dynamics of spot and futures prices in the presence of arbitrage. We propose a partially linear error correction model where the adjustment coefficient is allowed to depend non-linearly on the lagged price difference. We estimate our model using data on the DAX index and the DAX futures contract. We find that the adjustment is indeed nonlinear. The linear alternative is rejected. The speed of price adjustment is increasing almost monotonically with the magnitude of the price difference. JEL Classification: C32; C14; G13; G14

International evidence on sticky consumption growth (2008)

Christopher D. Carroll Jirka Slacalek Martin Sommer

We estimate the degree of 'stickiness' in aggregate consumption growth (sometimes interpreted as reflecting consumption habits) for thirteen advanced economies. We find that, after controlling for measurement error, consumption growth has a high degree of autocorrelation, with a stickiness parameter of about 0.7 on average across countries. The sticky-consumption-growth model outperforms the random walk model of Hall (1978), and typically fits the data better than the popular Campbell and Mankiw (1989) model. In several countries, the sticky-consumption-growth and Campbell-Mankiw models work about equally well. JEL Classification: E21, F41

Do markets love misery? : Stock prices and corporate philanthropic disaster response (2008)

Alan Muller Roman Kräussl

While companies have emerged as very proactive donors in the wake of recent major disasters like Hurricane Katrina, it remains unclear whether that corporate generosity generates benefits to firms themselves. The literature on strategic philanthropy suggests that such philanthropic behavior may be valuable because it can generate direct and indirect benefits to the firm, yet it is not known whether investors interpret donations in this way. We develop hypotheses linking the strategic character of donations to positive abnormal returns. Using event study methodology, we investigate stock market reactions to corporate donation announcements by 108 US firms made in response to Hurricane Katrina. We then use regression analysis to examine if our hypothesized predictors are associated with positive abnormal returns. Our results show that overall, corporate donations were linked to neither positive nor negative abnormal returns. We do, however, see that a number of factors moderate the relationship between donation announcements and abnormal stock returns. Implications for theory and practice are discussed. JEL Classification: G14, M21

Constructing the true art market index : a novel 2-step hedonic approach and its application to the german art market (2008)

Roman Kräussl Niels van Elsland

This study develops a novel 2-step hedonic approach, which is used to construct a price index for German paintings. This approach enables the researcher to use every single auction record, instead of only those auction records that belong to a sub-sample of selected artists. This results in a substantially larger sample available for research and it lowers the selection bias that is inherent in the traditional hedonic and repeat sales methodologies. Using a unique sample of 61,135 auction records for German artworks created by 5,115 different artists over the period 1985 to 2007, we find that the geometric annual return on German art is just 3.8 percent, with a standard deviation of 17.87 percent. Although our results indicate that art underperforms the market portfolio and is not proportionally rewarded for downside risk, under some circumstances art should be included in an optimal portfolio for diversification purposes. JEL Classification: G11

The economics of rating watchlists : evidence from rating changes (2008)

Christian Hirsch Christina E. Bannier

Generally, information provision and certifcation have been identified as the major economic functions of rating agencies. This paper analyzes whether the “watchlist” (rating review) instrument has extended the agencies' role towards a monitoring position, as proposed by Boot, Milbourn, and Schmeits (2006). Using a data set of Moody's rating history between 1982 and 2004, we find that the overall information content of rating action has indeed increased since the introduction of the watchlist procedure. Our findings suggest that rating reviews help to establish implicit monitoring contracts between agencies and borrowers and as such enable a finer partition of rating information, thereby contributing to a higher information quality. JEL: G14, G29, G33

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