Two longitudinal studies of marital interaction were conducted using observational coding of couples attempting to resolve a high-conflict issue. We found that a different pattern of results predicts concurrent marital satisfaction than predicts change in marital satisfaction over 3 years. Results

In this paper we analyze three and a half years of HTTP traffic observed at a small research institute to characterize the evolution of various facets of web operation. While our dataset is modest in terms of user population, it is unique in its temporal breadth. We leverage the longitudinal data

characteristics and the impact of the reception quality on user behavior. A unique aspect of our work is how to measure the reception quality of the video and its impact on the viewing behavior. We see that not even half of the videos are fully downloaded. For short videos of 3 minutes or less, users stop

The idea that wages rise relative to alternatives as job seniority accumulates is the foundation of the theory of specific human capital, as well as other widely accepted theories of compensation. The fact that persons with longer job tenures typically earn higher wages tends to support these views

This study examines a 118-year continuous record of retention and graduation rates at a public university for long-term trends not observable in shorter studies. While the first year retention rates stayed level over much of this period, second year rates increased steadily by 1.2 % per decade. In contrast, graduation rates at 4 years compared to 6 years declined by 1.9 % per decade. Even with large changes in cohort size and composition, these rates demon-strate remarkable stability over long periods, not varying by more than a few percent within narrow ranges. Considered in context with other institutional and student data, the patterns are reminiscent of those exhibited by complex adaptive systems. The state of equilibrium for the last 70 years is attributed to continuing co-adaptation between the capabilities and preparation of entering students and the expectations and requirements of the institution, implying that over the long-term, retention and graduation rates are measures of institutional stability rather than performance. As easily calculated measures of institutional success, retention and graduation rates have been investigated for decades. The earliest formal inquiries into student “mortality ” arose from the concerns of college registrars (Sage, 1927; West, 1925). Subsequent studies sought to quantify the phenomenon and explain its causes at individual institutions (Pettengill, 1938; Sheeder, 1939) and at groups of

Findings are presented from studies of the academic and language achievement of 1,307 young immigrant students whose educational history was traced from their arrival in Canada and entry into primary education in the early 1990s until their graduation from secondary schools. Five major findings are reported: school mobility, disappearance and dropout rates, success in provincial examinations, eligibility for postsecondary education, and ethnolinguistic differences in aca-demic success. Findings reveal distinct differences in academic success related to immigrant class, gender, and first language (L1), whereas differences related to age on arrival (AOA) are less apparent. These and other findings are reported and described, and implications for pedagogical policy are presented. Nous présentons les résultats d’études portant sur le rendement académique et langagier de 1 307 jeunes étudiants immigrants dont on a suivi le parcours édu-cationnel au Canada, de l’école primaire au début des années 1990 jusqu’à la fin de l’école secondaire. Nous traitons de cinq aspects majeurs: mobilité scolaire; disparition et décrochage; réussite aux examens de la province; admissibilité aux

A procedure is described for obtaining information concerning the circularity of fiber cross-sections from measurements made in a longitudinal view of the fibers. A method is developed for mewing and measuring the projected diameter of fibers viewed longitudinally, and an analytical procedure

Seventy-three couples were studied at 2 time points 4 years apart. A typology of 5 groups of couples is proposed on the basis of observational data of Time 1 resolution of conflict, specific affects, and affect sequences. Over the 4 years, the groups of couples differed significantly in serious considerations of divorce and in the frequency of divorce. There were 3 groups of stable couples: validators, volatiles, and avoiders, who could be distinguished from each other on problem-solving behavior, specific affects, and persuasion attempts. There were 2 groups of unstable couples: hostile and hostile/detached, who could be distinguished from each other on problem-solving behavior and on specific negative and positive affects. A balance theory of marriage is proposed, which explores the idea that 3 distinct adaptations exist for having a stable marriage.

Abstract. Europe has a long history of cartels, but the changes in the scale and geography of collusion in the European market from the post-war decades until the present have not been systematically investigated. Using network analysis methods and an original dataset based on decisions in EU cartel cases, this paper maps the developments in detected collusion in the European market from 1958 to 2008 and tentatively explains these developments. It appears that collusive activities increased during the 1960s and after the mid-1980s and that a long decline in the scale of collusion began in the mid-1990s. Moreover, the geographical spread of collusive activities in Europe increased considerably from 1969 to 1993. To facilitate an explanation of these and other findings, the paper presents a threedimensional analytical framework that emphasises the importance of anticartel regulation, major changes in the business environment and the size of national economies.

The authors thank Catherine Maclean for helpful comments. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research. NBER working papers are circulated for discussion and comment purposes. They have not been peer