In the article, presented are sufficient and necessary conditions for a class of functions involving the ratio of two gamma functions to be logarithmically completely monotonic. From this, some inequalities for bounding the ratio of two gamma functions are refined, extended and sharpened readily, and double inequalities on the divided differences of the psi and polygamma functions are derived s...

The distinction of between-person age differences from within-person age changes is necessary for understanding aging-related change processes. Although longitudinal studies are required to address issues relating to within person change, most studies begin using age-heterogeneous samples and conclude using survival-heterogeneous samples. Given the numerous potential confounds associated with a...

Using data from two surveys in three counties where the prevalence of uxorilocal marriage differs greatly, this paper analyzes the effects of marriage form, individual, family and social factors on age at first marriage and spousal age difference. The results show that, under the Chinese patrilineal joint family system, compared with the dominant virilocal marriage form, uxorilocal marriage sig...

Preferences for certain age characteristics of partners are reported across cultures: men prefer mates who are younger and women prefer mates older than themselves. To examine whether these age preferences entail fitness effects for men and women, we investigated the association among age differences between partners and offspring count. On the basis of a sample of approximately 10,000 post-rep...

Block Design tasks are neuropsychologically valuable, but standard scoring sacrifices potentially useful information that could elucidate the cognitive processes underlying performance failures. Qualitative indices that were proposed in the WAIS-R-NI [Kaplan, E., Fein, D., Morris, R., & Delis, D. (1991). The WAIS-R as a neuropsychological instrument [Manual]. San Antonio, TX: Psychological Corp...

In this experiment we explored age differences in frequency judgment. Young and older adults studied words occurring from one to six times under divided or focused attention and then completed either a frequency discrimination or a frequency estimation test for these items. Divided attention led to poorer performance on both frequency judgment tests, suggesting that distraction during the encod...

Age differences in emotional experience, expression, and control were investigated in 4 studies. A community sample of 127 African Americans and European Americans (ages 19-96 years) was used in Study 1; a community sample of 82 Chinese Americans and European Americans (ages 20-85 years) was used in Study 2; a community sample of 49 Norwegians drawn from 2 age groups (ages 20-35 years and 70+ y...

Three experiments are reported on implicit learning in 432 children between the ages of 4 and 10 years, using a new paradigm ("the neutral parameter procedure") based on drawing behavior. The first two experiments demonstrated that children modified their drawing behavior following specially devised practice in such a way that these modifications could not be viewed as the result of deliberate ...

Previous research has suggested that an age-related decline in change detection may be due to older adults using a more conservative response criterion. However, this finding may reflect methodological limitations of the traditional change detection design, in which displays are presented continuously until a change is detected. Across 2 experiments, the authors assessed adult age differences i...