Measurement error and panel data1

The underidentification of linear models with measurement error does not necessarily extend to panel data models, as has been shown by GAiliches and Hausman (1986). We discuss and extend some of their results for a simple case and address particular issues concerning identification and asymptotic variances.     

Exploitation rate,survival and movements of brown trout (Salmo trutta L.) stocked at takeable size in the regulated rivers Lågen and Otta,southern Norway

Takeable size (age 4⁺, length 27–67cm), hatchery reared brown trout (Salmo trutta L.) were released into the rivers Lågen and Otta, the Glomma River System, southern Norway, in May-July 1981 and 1983–87. The brown trout released in May gave significantly lower recapture rates compared to those released in June/July, i.e. 22.8 per cent compared to 41.6–58.0 per cent, respectively. Mean exploitation rate and survival rates ranged from 0.23 to 0.58 and 0.2 to 0.4, respectively, Within 15 days after release 50 per cent were recaptured, and 90 per cent were caught within 67 days. The frequency of recapture increased significantly with fish length in the length interval 30–45 cm, but decreased for bigger fish. The stocked brown trout were stationary and 95 per cent of the recaptures were caught less than 1 km from the site of release. Frequency of recapture ranged from 19.2 to 54.7 per cent in 6 experiments with takeable sized brown trout in different tributaries of the Glomma River System, and the variations are probably mainly due to differences in fishing pressure.     

Simulation of sulfide buildup in wastewater and atmosphere of sewer networks.

A model concept for prediction of sulfide buildup in sewer networks is presented. The model concept is an extension to--and a further development of--the WATS model (Wastewater Aerobic-anaerobic Transformations in Sewers), which has been developed by Hvitved-Jacobsen and co-workers at Aalborg University. In addition to the sulfur cycle, the WATS model simulates changes in dissolved oxygen and carbon fractions of different biodegradability. The sulfur cycle was introduced via six processes: 1. sulfide production taking place in the biofilm covering the permanently wetted sewer walls; 2. biological sulfide oxidation in the permanently wetted biofilm; 3. chemical and biological sulfide oxidation in the water phase; 4. sulfide precipitation with metals present in the wastewater; 5. emission of hydrogen sulfide to the sewer atmosphere and 6. adsorption and oxidation of hydrogen sulfide on the moist sewer walls where concrete corrosion may take place.     

Modelling faecal coliforms dynamics in the Seine estuary, France.

A model describing the dynamics of faecal coliforms (FC) in the Seine estuary has been developed and coupled with a three-dimensional hydrodynamic model. As input to this model three types of FC sources were considered: (1) FC transported by the Seine river flow at the estuary entrance at Poses dam; (2) FC brought in through the tributaries of the Seine estuary; and (3) the outfalls of the treated effluents of the WWTPs located along the estuary. As previous studies in the Seine estuary showed that a large proportion of FC was attached to SM, two pools of FC were considered separately in the model: free FC and FC attached to SM. Two main processes controlling the fate of FC in the estuary were considered: mortality and settling. The model calculates for a given discharge of the Seine river at Poses the longitudinal distribution of FC along the estuary. The model was validated by comparison of model calculations with experimental data in various hydrological conditions. The model also correctly reproduced the impact of the main river flow rate on the level of estuarine water's contamination. Finally, the model was used to test different scenarios of sanitation, suggesting priorities for sanitation efforts.     

Parathion degradation and toxicity reduction in solar photocatalysis and photolysis.

The solar photocatalytic degradation of methyl parathion was investigated using a circulating TiO2/solar light reactor. Under solar photocatalysis condition, parathion was more effectively degraded than solar photolysis and TiO2-only conditions. With solar photocatalysis, 20 mg/L of parathion was completely degraded within 60 min with a TOC decrease of 63% after 150 min. The main ionic byproducts during photocatalysis recovered from parathion degradation were mainly as NO3-, NO2- and NH4+, 80% of the sulphur as SO4(2-), and 5% of phosphorus as PO4(3-). The organic intermediates 4-nitrophenol and methyl paraoxon were also identified, and these were further degraded in solar photocatalytic condition. Two different bioassays (Vibrio fischeri and Daphnia magna) were used to test the acute toxicity of solutions treated by solar photocatalysis and photolysis. The Microtox test using V. fischeri showed that the toxicity expressed as EC50 (%) value increased from 5.5% to >82% in solar photocatalysis, indicating that the treated solution is non-toxic, but only increased from 4.9 to 20.5% after 150 min in solar photolysis. The acute toxicity test using D. magna showed that EC50 (%) increased from 0.05 to 1.08% under solar photocatalysis, but only increased to 0.12% after 150 min with solar photolysis, indicating the solution is still toxic. The pattern of toxicity reduction parallels the decrease in TOC and the parathion concentrations.     

Analysis of interbudgetary financial flows in the Republic of Buryatia in 2001–2005

Financial flows between center and region are analyzed on the example of the Republic of Buryatia. Significant changes are shown to have occurred in the interbudgetary relations between the federal center and the region, which are associated with a revised delineation of authorities between different levels of authority. It has been the key factor in changing the sources and volumes of financial flows. The analysis is largely focused on the relations between the region and its municipalities.     

Call Options and Liquidation in Commercial Mortgage Financing

This paper models a commercial real estate project where a wealth-constrained manager uses outside debt financing to purchase a project who's return depends on future economic conditions and the manager's investment in the project. It is shown that it is inefficient to finance the project with callable debt. This prediction is consistent with observed real estate financing practice. I also model the outcome of financial distress allowing for (1) debt forgiveness, (2) equity in exchange for debt forgiveness, and (3) foreclosure. The model motivates (1) why commercial real estate loans are often foreclosed, and (2) why lenders foreclose assets at fire-sale prices.     

AN EMPIRICAL EXAMINATION OF RELATIONSHIP MAGNITUDE

Based upon a review of the extant literature, it is proposed that the structure of an interorganizational relationship is composed of relationship type and the under‐researched construct of relationship magnitude. Specifically, it is hypothesized that relationship magnitude, a second order construct composed of trust, commitment, and dependence, affects relationship type, which affects the perception of value of the relationship. The results of a survey analyzed through structural equation modeling support these hypotheses.