Local expectations hypothesis

The local expectations hypothesis states that all bonds will generate the same expected rate of return if held for a small term. It is expressed formally in (3.39). 

This version of the hypothesis is the only one that permits no arbitrage, because the expected rates of return on all bonds are equal to the risk-free interest rate. For this reason, the local expectations hypothesis is sometimes referred to as the risk-neutral expectations hypothesis. 

Computational previews of stable particle-like organizing centers have been completed using excitable media with electrophysiological rather than chemical mechanisms [23, 30, 31]. There seems no reason to expect qualitatively different behavior in the Oregonator mechanism or the Belousov-Zhabotinsky reagent, but this expectation has thus far been tested both computationally and in the laboratory only for the dynamical consequences of twist on an arc of initially straight filament (see Sections 4 and 5 below). How are we to quantitatively inquire into the dynamics of vortex filaments The only approach undertaken to date is based on the Local Geometry Hypothesis . 

Clarke, Kassel, and Storeh5 interpret the slow adsorption on chromic oxide gel as in part a diffusion of an already adsorbed layer to secondary centres of adsorption but Burwell and Taylor criticize the whole diffusion hypothesis, partly on the grounds that the temperature coefficient of the rate of adsorption is not that to be expected for diffusion.6 It may not, however, be easy to distinguish between the gross characteristics of an activated diffusion along the surface, and of an activated adsorption indeed it seems just admissible to consider the former as a localized form of the latter. 

An interesting example of a well defined localized perturbation of the plankton ecosystem was produced by the SOIREE iron fertilization experiment (Abraham et al., 2000) with the aim to test the hypothesis of iron limitation of growth in regions with high nutrient, but low natural phytoplankton concentration. As it was expected,... 

The alternative hypothesis, that of a nucleosynthetic component carried into the early solar system by 0-rich presolar dust (see discussion in Clayton 1993) remains plausible after all, as mentioned in the Introduction, trace amounts of presolar dust is known to exist in the matrices of chondrites. However, all the high spatial (ion microprobe) measurements of the many types of primitive refractory materials discussed here have failed to find any very extreme oxygen isotopic anomalies such as might be expected if pure 0 dust (e.g. from a supernova) were incorporated into CAIs or AOAs along with local condensates. Even among the -100 true interstellar oxide grains that... 

The underlying hypothesis is that because EC and primary OC often have the same sources, there is a representative ratio of OC/EC for the primary aerosol. If the measured ambient OC/EC ratio exceeds this expected value, then the additional OC can be considered to be secondary in origin. A weakness of that approach is that OC/EC emission rates vary by source and therefore the primary ratio will be influenced by meteorology, diurnal and seasonal fluctuations in emissions, and local sources. 

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