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Martin Daly

Publications and source records attributed to Martin Daly.

5 recordsLinked to original sources
PubMed2006

Are juvenile offenders extreme future discounters?

It has been the prevailing view that young offenders are more present oriented than their peers, but this view has little empirical basis other than the actions that have defined these youth as offenders. In the present study, we used a decision task with actual monetary consequences to assess the tendency of young offenders and a control group of high school students to discount the future. The young offenders were not significantly different from the students in discounting the future, even though the young offenders scored significantly higher on a sensation-seeking personality scale, were less likely to have lived with their fathers, and had changed schools more often. Young offenders and control participants were also similar in the extent to which they manifested a clear vision of the future by anticipating which future milestones would occur sooner, in a task pairing milestones with each other and with year markers.

Adolescent↗
PubMed2005

Carpe diem: adaptation and devaluing the future.

Organisms typically "discount the future" in their decision making, but the extent to which they do so varies across species, sexes, age classes, and circumstances. This variability has been studied by biologists, economists, psychologists, and criminologists. We argue that the conceptual framework required for an interdisciplinary synthesis of knowledge in this area is the evolutionary adaptationist analysis of reproductive effort scheduling pioneered by George Williams.

Age Factors↗
PubMed2004

Do pretty women inspire men to discount the future?

Organisms 'discount the future' when they value imminent goods over future goods. Optimal discounting varies: selection should favour allocations of effort that effectively discount the future relatively steeply in response to cues promising relatively good returns on present efforts. However, research on human discounting has hitherto focused on stable individual differences rather than situational effects. In two experiments, discounting was assessed on the basis of choices between a smaller sum of money tomorrow and a larger sum at a later date, both before and after subjects rated the 'appeal' of 12 photographs. In experiment 1, men and women saw either attractive or unattractive opposite-sex faces; in experiment 2, participants saw more or less appealing cars. As predicted, discounting increased significantly in men who viewed attractive women, but not in men who viewed unattractive women or women who viewed men; viewing cars produced a different pattern of results.

Adult↗
PubMed2003

Effect of predation risk on selectivity in heteromyid rodents.

Variations in predation risk affect the costs of foraging and may therefore warrant different foraging decisions. One class of models ("higher requisite profit") predicts that foragers should become more selective when predation risk increases, as low-profitability items that do not cover the increased costs are dropped from the diet. An alternative class of models ("reduced finickiness") predicts that foragers should become less selective when predation risk increases, because selectivity requires more extensive assessment and/or search behaviour, prolonging exposure to risk. We assessed the selectivity of foraging heteromyid rodents (Merriam's kangaroo rats, Dipodomys merriami, and pocket mice, Chaetodipus spp.) by comparing differences in "giving up densities" (GUD: the quantity of cryptic food left in a patch by animals for whom the diminishing marginal gains from foraging have dropped below the threshold for continued search) for foods of different value as a measure of selectivity in patches varying in predation risk. Data collected over two field seasons revealed that heteromyids were more selective when predation risk was highest; away from the protective cover of shrubs during the full moon. These findings support the predictions of higher requisite profit models.

Journal Article↗