BACKGROUND Sunscreen use and dietary antioxidants are advocated as preventives of skin aging, but supporting evidence is lacking. OBJECTIVE To determine whether regular use of sunscreen compared with discretionary use or β-carotene supplements compared with placebo retard skin aging, measured by degree of photoaging. DESIGN Randomized, controlled, community-based intervention. (Australian N...

OBJECTIVE We examined whether trajectories of dietary patterns from 6 to 24 months of age are associated with intelligence quotient (IQ) in childhood and adolescence. METHODS Participants were children enrolled in a prospective UK birth cohort (n = 7,652) who had IQ measured at age 8 and/or 15 years. Dietary patterns were previously extracted from questionnaires when children were aged 6, 15 ...

We examine how the criteria for choosing estimation samples (peer firms) affect the ability to detect discretionary accruals, using several variants of the Jones (1991) model. Researchers commonly estimate accruals models in cross-section, and define the estimation sample as all firms in the same industry. We examine whether firm size performs at least as well as industry membership as the crit...

The open and anonymous of grid make the task of controlling access to sharing information more difficult, which cannot be addressed by traditional access control methods. In this paper, we identify access control requirements in such environments and propose a trust based access control framework for grid resource sharing. The framework is an integrated solution involving aspects of trust and r...

Multitasking is prevalent during computer-mediated work. Users tend to switch between multiple ongoing computer-based tasks either due to a personal decision to break from the current task (self-interruption) or due to an external interruption, such as an electronic notification. To examine how different types of multitasking, along with subjective task difficulty, influence performance, we con...

Discretionary policymakers cannot manage private-sector expectations and cannot coordinate the actions of future policymakers. As a consequence, expectations traps and coordination failures can occur and multiple equilibria can arise. To utilize the explanatory power of models with multiple equilibria it is first necessary to understand how an economy arrives to a particular equilibrium. In thi...

Managers can decide to reduce a warrant’s exercise price. A reduction in exercise price can induce exercise (a conversion-forcing reduction) or not (a long-term reduction). Conversionforcing firms show an abnormal return of -1.53% on the announcement day but they perform well over the three years following the announcement. This finding suggests that the funds raised from warrant exercise are i...

We describe a simple mechanism that generates inflation persistence in a standard sticky-price model of optimal fiscal and monetary policy. Key to this mechanism is that policies are implemented under discretion. The government’s discretionary incentive to erode the real value of nominal public debt by means of surprise inflation renders inflation expectations and, in further consequence, equil...

We discuss the finite-fuel, singular stochastic control problem of optimally tracking the standard Brownian motion x+W (·) started at x ∈ IR, by an adapted process ξ(·) = ξ+(·)−ξ−(·) of bounded total variation ξ̌(t) = ξ+(t) + ξ−(t) ≤ y, ∀ 0 ≤ t < ∞, so as to minimize the total expected discounted cost

Explores whether the firm's discretionary narrative disclosures measure its financial risk of bankruptcy. Specifically examines the existence of an association between the content of the chairman's statement and firm failure. Show that these statements are closely associated with financial performance, reinforcing the argument that such unaudited disclosures contain important information. The r...