Young and old adults were compared in their efficiency of remembering concurrently presented . series ofletters and digits in three separate experiments. Instructions and payoffs to vary attenI tional emphasis across the two types of material in different conditions allowed the examination I ofattention-operating characteristics in the two age groups. Strategy-independent measures deI rived fro...

We compared young and healthy older adults' ability to rate photos of faces and situations (e.g., sporting activities) for the degree of threat they posed. Older adults did not distinguish between more and less dangerous faces to the same extent as younger adults did. In contrast, we found no significant age differences in young and older adults' ability to distinguish between high- and low-dan...

Sixty young and 60 elderly adults completed a pencil-and-paper addition test and solved 40 computer-presented simple addition problems. Strategies and problem solution times were recorded on a trial-by-trial basis and were classified in accordance with the distributions of associations model of strategy choices. The elderly group showed a performance advantage on the ability measure and for the...

making decision about capital structure is one of the hardest and challengeable problems for the companies, and also it is the greatest importance decision about their permanence. this paper investigates factors affecting capital structure among 70 samples of small business in ahwaz. data was gathered from accounting evidences and data questioners. parametric and nonparametric statistical techn...

E-commerce will undoubtedly change the way business is done. But as we have said elsewhere, “technology changes, economic laws do not.” Despite the changes introduced by e-commerce, many of the fundamental principles of competition will still be relevant. In this paper I investigate three aspects of competition in ecommerce: marketing, interconnection, and price matching. In each case I will de...

The effect of changes in age structure on economic growth has been widely studied in the demography and population economics literature. The beneficial effect of changes in age structure after a decrease in fertility has become known as the demographic dividend. In this paper we first present the motivation for also explicitly addressing changes in education in addition to and age structure and...

There is significant recent interest in Peto's paradox and the related problem of the evolution of large, long-lived organisms in terms of cancer robustness. Peto's paradox refers to the expectation that large, long-lived organisms have a higher lifetime cancer risk, which is not the case: a paradox. This paradox, however, is circular: large, long-lived organisms are large and long-lived becaus...