45 research outputs found
An optimal portfolio, consumption-leisure and retirement choice problem with CES utility: a dynamic programming approach
On the optimal investment
In 1988 Dybvig introduced the payoff distribution pricing model (PDPM) as an alternative to the capital asset pricing model (CAPM). Under this new paradigm agents preferences depend on the probability distribution of the payoff and for the same distribution agents prefer the payoff that requires less investment. In this context he gave the notion of efficient payoff. Both approaches run parallel to the theory of choice of von Neumann -Morgenstern (1947), known as the Expected Utility Theory and posterior axiomatic alternatives. In this paper we consider the notion of optimal payoff as that maximizing the terminal position for a chosen preference functional and we investigate the relationship between both concepts, optimal and efficient payoffs, as well as the behavior of the efficient payoffs under different market dynamics. We also show that path-dependent options can be efficient in some simple models
The Complete Genome Sequence of Mycoplasma bovis Strain Hubei-1
Infection by Mycoplasma bovis (M. bovis) can induce diseases, such as pneumonia and otitis media in young calves and mastitis and arthritis in older animals. Here, we report the finished and annotated genome sequence of M. bovis strain Hubei-1, a strain isolated in 2008 that caused calf pneumonia on a Chinese farm. The genome of M. bovis strain Hubei-1 contains a single circular chromosome of 953,114 bp with a 29.37% GC content. We identified 803 open reading frames (ORFs) that occupy 89.5% of the genome. While 34 ORFs were Hubei-1 specific, 662 ORFs had orthologs in the M. bovis type strain PG45 genome. Genome analysis validated lateral gene transfer between M. bovis and the Mycoplasma mycoides subspecies mycoides, while phylogenetic analysis found that the closest M. bovis neighbor is Mycoplasma agalactiae. Glycerol may be the main carbon and energy source of M. bovis, and most of the biosynthesis pathways were incomplete. We report that 47 lipoproteins, 12 extracellular proteins and 18 transmembrane proteins are phase-variable and may help M. bovis escape the immune response. Besides lipoproteins and phase-variable proteins, genomic analysis found two possible pathogenicity islands, which consist of four genes and 11 genes each, and several other virulence factors including hemolysin, lipoate protein ligase, dihydrolipoamide dehydrogenase, extracellular cysteine protease and 5′-nucleotidase
Spending rules for endowment funds
Endowment fund managers face an asset allocation problem with several particularities: they are more interested in spending for current and future beneficiaries than growing value, although the trade-off between these two alternatives needs to be understood; they have to consider longest-term investment, typically an infinite horizon. We do address these allocation constraints in a dynamic framework where minimum subsistence levels (introducing the idea that a minimum spending amount needs to be made at every time period) are introduced in the objective function. We derive explicit formulas for the optimal spending stream, endowment value, spending rate and portfolio strategy in a simple Black/Scholes type economy. We analyze the effects of parameter changes on asset allocation decisions and provide simulations on bearish, median and bullish paths. Copyright Springer Science + Business Media, LLC 2006