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Investment Theory (investment + theory)
Kinds of Investment Theory Selected AbstractsA new vision for the field: Introduction to the second special issue on the unified theoryJOURNAL OF CLINICAL PSYCHOLOGY, Issue 1 2005Gregg R. Henriques This is the second of two issues of the Journal of Clinical Psychology focused on the validity and usefulness of a new theoretical vision for the field (Henriques, 2003). The first two contributions from Rand and Ilardi and Geary both enrich the argument that psychology needs to be effectively connected with biology and physics and that the unified theory (via Behavioral Investment Theory) is highly successful in this way. The authors of the subsequent three articles,Shaffer, Quackenbush, and Shealy,show that the Tree of Knowledge System (through the Justification Hypothesis) is deeply commensurate with the dominant paradigms in the social sciences. Thus, the group of authors of these five articles demonstrates the viability of the unified theory both from bottom-up and top-down viewpoints. In the sixth article, the author addresses some important problems that potentially arise with the development of a clearly defined discipline. In the concluding article I address the concerns about the proposal raised by the contributors to the two special issues and articulate how the unified theory lays the foundation for the development of a useful mass movement in psychology. © 2004 Wiley Periodicals, Inc. J Clin Psychol. [source] Portfolio theory and how parent birds manage investment riskOIKOS, Issue 10 2009Scott Forbes Investment theory is founded on the premise that higher returns are generally associated with greater risk, and that portfolio diversification reduces risk. Here I examine parental investment decisions in birds from this perspective, using data from a model system, a 16-year study of breeding red-winged blackbirds Agelaius phoeniceus. Like many altricial birds, blackbirds structure their brood into core (first-hatched) and marginal (later-hatched) elements that differ in risk profile. I measured risk in two ways: as the coefficient of variation in growth and survival of core and marginal offspring from a given brood structure; and using financial beta derived from the capital asset pricing model of modern portfolio theory. Financial beta correlates changes in asset value with changes in the value of a broader market, defined here as individual reproductive success vs. population reproductive success. Both measures of risk increased with larger core (but not marginal) brood size; and variation in growth and survival was significantly greater during ecologically adverse conditions. Core offspring showed low beta values relative to marginal progeny. The most common brood structures in the population exhibited the highest beta values for both core and marginal offspring: many parent blackbirds embraced rather than avoided risk. But they did so prudently with an investment strategy that resembled a financial instrument, the call option. A call option is a contingent claim on the future value of the asset, and is exercised only if asset value increases beyond a point fixed in advance. Otherwise the option lapses and the investor loses only the initial option price. Parents created high risk marginal progeny that were forfeited during ecological adversity (the option lapses) but raised otherwise (the option called); at the same time parents maintained a constant investment and return in low risk core progeny that varied little with changes in brood size or ecological conditions. [source] Nest Crypsis, Reproductive Value of a Clutch and Escape Decisions in Incubating Female Mallards Anas platyrhynchosETHOLOGY, Issue 8 2004Albrecht In cryptically coloured birds, remaining on the nest despite predator approach (risk-taking) may decrease the likelihood that the nest will be detected and current reproductive attempt lost. By contrast, flushing may immediately reveal the nest location to the predator. Escape decisions of incubating parents should therefore be optimized based on the risk-to-parent/cost of escape equilibrium. Animal prey may assess predation risk depending on a variety of cues, including the camouflage that vegetation provides against the predator. We examined interactive effects of nest crypsis and the current reproductive value of a clutch on flushing distances in incubating mallards (Anas platyrhynchos) approached by a human. Our results were consistent with predictions of parental investment theory: flushing distances were inversely correlated with measures of the reproductive value of the current clutch, namely with clutch size, stage of incubation and mean egg volume. Independently of a reproductive value of a clutch, nest concealment explained a significant portion of the variation in flushing distance among females; individual females tended to increase/decrease flushing distances according to change in nest cover. The results further suggest that vegetation concealment greatly influenced the risk of nest detection by local predators, suggesting that vegetation may act as a protective cover for incubating female. A female's ability to delay flushes according to the actual vegetation cover might thus be viewed as an antipredator strategy that reduces premature nest advertising to visually oriented predators. We argue, however, that shorter flying distances from densely covered sites might be maladaptive in areas where a predator's ability to detect incubating female does not rely on visual cues of nests. [source] Perinatal Sadness among Shuar Women: Support for an Evolutionary Theory of Psychic PainMEDICAL ANTHROPOLOGY QUARTERLY, Issue 1 2007Edward H. Hagen Psychiatry faces an internal contradiction in that it regards mild sadness and low mood as normal emotions, yet when these emotions are directed toward a new infant, it regards them as abnormal. We apply parental investment theory, a widely used framework from evolutionary biology, to maternal perinatal emotions, arguing that negative emotions directed toward a new infant could serve an important evolved function. If so, then under some definitions of psychiatric disorder, these emotions are not disorders. We investigate the applicability of parental investment theory to maternal postpartum emotions among Shuar mothers. Shuar mothers' conceptions of perinatal sadness closely match predictions of parental investment theory. [source] Breastfeeding structure as a test of parental investment theory in Papua New Guinea,AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 5 2009David P. Tracer Evolutionary parental investment theory predicts that parents invest preferentially in offspring best able to translate investments into fitness payoffs. It has also been proposed that where the reproductive prospects of offspring are directly correlated with parental investment and variance in fertility is higher for males than females, parents in better condition should bias investment toward males while those in poorer condition should bias investment toward females. Lactation is arguably among the costliest forms of investment expended by mothers and is thus expected to be allocated in ways consistent with fitness payoffs. Quantitative data collected among 110 Papua New Guinean mother-infant pairs during 470 h of focal follows on nursing frequency and duration and responses to infant demands by maternal and offspring characteristics are presented to provide empirically-based descriptions of infant care and tests of evolutionary parental investment theory. Results indicate that mothers show very high levels of investment in offspring. However, although breastfeeding in developing countries is often characterized as on-demand, fussing and crying by infants were only attended to with breastfeeding about 30% of the time. Contrary to expectations of parental investment theory that parents should invest less in poorer quality offspring, mothers increased investment in offspring in poorer condition. The expectation that mothers in better condition would bias investment toward male offspring was also not supported; better nourished mothers biased investment toward female offspring. This study illustrates how infant feeding data may be used for testing larger evolutionary questions such as those derived from parental investment theory. Am. J. Hum. Biol. 2009. © 2009 Wiley-Liss, Inc. [source] Does the Theory of Irreversible Investments Help Explain Movements in Office,Commercial Construction?REAL ESTATE ECONOMICS, Issue 4 2000Rena Sivitanidou Focusing on the relevance of the modern investment theory in explaining movements in office,commercial construction, we attempt to advance existing empirical work in two respects. First, building on recent theoretical advances, we offer an extended empirical model of new construction that takes into account the full opportunity cost of irreversible investments in uncertain environments. Second, using updated time series of office,commercial construction across the nation's largest markets, we empirically estimate such a model to (i) explore investment behavior during 1982,1998 and (ii) detect differences, if any, in such behavior between the pre- and post-recession years. Our empirical findings are fully consistent with the theory of irreversible investments. Such findings highlight both the relevance and the relative importance of uncertainty in underlying demand factors in shaping movements in office,commercial construction, while pointing altogether to more cautionary investment behavior during the post-recession years. [source] Investment planning under uncertainty and flexibility: the case of a purchasable sales contract*AUSTRALIAN JOURNAL OF AGRICULTURAL & RESOURCE ECONOMICS, Issue 1 2008Oliver Musshoff Investment decisions are not only characterised by irreversibility and uncertainty but also by flexibility with regard to the timing of the investment. This paper describes how stochastic simulation can be successfully integrated into a backward recursive programming approach in the context of flexible investment planning. We apply this hybrid approach to a marketing question from primary production which can be viewed as an investment problem: should grain farmers purchase sales contracts which guarantee fixed product prices over the next 10 years? The model results support the conclusion from dynamic investment theory that it is essential to take simultaneously account of uncertainty and flexibility. [source] Asset allocation and age effects in retirement savings choicesACCOUNTING & FINANCE, Issue 2 2010Paul Gerrans D91; G11; D14 Abstract We examine the asset allocation decisions of members of three large Australian retirement savings funds. Superannuation Guarantee legislation in 1992 made Australian employees compulsory investors by requiring employers to contribute a fixed proportion of earnings to a superannuation fund on behalf of employees. A majority of these employees can choose an investment strategy for these contributions. We examine how actual investment strategy and asset allocation choices of members change with age in view of the conventional wisdom that individuals allocate less to risky assets as they age and investments theory which provides conflicting advice on the issue. [source] | |||||||||||||