Everyday activities break down into parts and subparts, and appreciating this hierarchical structure is an important component of understanding. In two experiments we found age differences in the ability to perceive hierarchical structure in continuous activity. In both experiments, younger and older adults segmented movies of everyday activities into large and small meaningful events. Older ad...

We study the causal effects of digitizing work on information workers’ time-use and performance at a large insurance firm. We make causal inferences and obtain unbiased estimates by exploiting a quasi-experiment: the phased introduction of Electronic Document Management (EDM) across multiple offices at different dates. We apply a difference-in-differences methodology to econometrically measure ...

The purpose of this study was to examine the effect of practice on simple reaction time (RT), movement time (MT), and response consistency for two arm-reaching tasks of graded complexity in younger and older adults. Forty subjects, 20 younger adults (age range = 20-29 years) and 20 older adults (age range = 60-82 years), were randomly subdivided into practice and control groups. All subjects we...

The current study examined age differences in the association between daily negative affect, average negative affect, and diurnal cortisol among participants from the National Study of Daily Experiences (N = 1,423; age range: 33-84 years). Across four consecutive days, participants reported the negative emotions they experienced and provided four saliva samples per day, from which cortisol was ...

While older adults face various deficits in binding items in memory, they are often able to remember information that is deemed important. In Experiment 1, we examined how younger and older adults remember medication interactions of varying severity. There were no age differences in overall memory accuracy, but older adults' performance depended on the severity of the interactions (such that th...

This article describes both normative changes and individual differences in the gender composition of girls' and boys' friendship networks across adolescence and predicts variations in these changes. It also examines changes in the characteristics (context, age difference, closeness, and support) of same- and other-sex friendships in the network. Girls and boys (N=390) were interviewed annually...

This study investigated whether young and older adults vary in their beliefs about the impact of various mitigating factors on age-related memory decline. Eighty young (ages 18-23) and 80 older (ages 60-82) participants reported their beliefs about their own memory abilities and the strategies that they use in their everyday lives to attempt to control their memory. Participants also reported t...

A divided difference expansion with remainder for a general divided difference is derived that contains Floater’s recent derivative expansion as a special case. key words divided difference, univariate, remainder, interpolation

Two experiments are reported that compared younger and older adults on their performance of two bimanual temporal coordination tasks at varying movement speeds. In many cases, older adults performed as well as younger adults at all speeds of an in-phase coordination pattern and at slow speeds of an anti-phase pattern for both coordination accuracy and stability. Age differences tended to emerge...

In this paper we empirically test whether public R&D subsidies crowd out private R&D investment in Flanders and Germany, using firm level data from the Flemish and German part of the Community Innovation survey (CIS III and IV). Both the non-parametric matching estimator and the conditional difference-in-difference estimator with repeated cross-sections (CDiDRCS) clearly indicate that the crowd...