Curved Chaotic Map Time Series Models and Their Stochastic Reversals

This paper considers two types of chaotic map time series models, including the well-known tent, logistic and binary-shift maps as special cases; these are called curved tent and curved binary families. Deterministic behaviour is investigated by invariant distributions, Lyapunov exponents, and by serial dependency. Stochastic time reversal of the families is shown to produce models which have a broader range of stochastic and chaotic properties than their deterministic counterparts. The marginal distributions may have concentrations and restricted supports and are shown to be a non-standard class of invariant distribution. Dependenc y is generally weaker with the reversed stochastic models. The work gives a broad statistical account of deterministic and stochastically reversed map models, such as are emerging in random number generation, communica tion systems and cryptography     

A tobacco and alcohol use profile of San Francisco's Chinese community

Relatively little is known about Asian American tobacco and alcohol use patterns. This is particularly true of Chinese living in the United States--either U.S.-born or non-U.S.-born Chinese. This article presents data from a research project studying tobacco and alcohol use patterns in San Francisco's Chinese community. Data were secured both from focus groups and a self-report telephone survey of a random sample of 1,808 Chinese residents in San Francisco. This results indicate that the prevalence of both tobacco and alcohol use is lower for San Francisco's Chinese population than for the general population. Moreover, those persons who report smoking tend to be different from those who report consuming alcohol. The study concludes that specific, culturally relevant tobacco and alcohol prevention programs should be designed to better reach this target population.     

Severely Traumatized Siblings: A Treatment Strategy

Siblings who have suffered severe trauma and disrupted attachment relate to one another in ways that interfere with individual development, the chance to benefit from connections with adults, the establishment of healthy sibling relationships, and the working through of traumatic experiences. The authors use case examples to illustrate four distinct sibling patterns: absent, adult lockout, half and half, and trauma shield. The authors highlight the importance of recognizing these types and then varying the therapist's treatment stance to pursue five goals. These include suspending problematic sibling relationships to create room for bonding with caring adults, transferring attachment behaviors and impulses to a receptive adult, resuming healthy individual development, forming more adaptive sibling connections, and expressing shared traumatic content.     

Clinical reengineering. A benchmark strategy

The health care provider marketplace continues to undergo dramatic changes with the advent of hospital mergers, acquisitions, and physician and hospital alliances. In this era of managed care, cost containment is still vital to a hospital's success, but many stakeholders--patients, employers, and physicians--are determined that quality of care also remain paramount. How can hospitals reduce their expenses and maintain a quality focus? The answer lies in a successful clinical reengineering initiative. One progressive model of clinical reengineering is presented, as well as examples of initiatives at three health care institutions. Initial results of clinical redesign programs have been dramatic and encouraging, with documented evidence of simultaneous cost savings and improved patient care.     

Health care 2015: flight of the butterfly

Projecting out to the year 2015 sounds presumptuous. Who can predict that far ahead? Perhaps no one can. Social and organizational arrangements come slowly. It takes five years or so to implement simple concepts, sometimes decades for more radical changes. Once you have the ideas in tangible form, it can take another five years to get it working right. Early adopters bring others into the movement and, over 15-25 years, new directions dominate. It takes at least a generation of new practitioners to take on the new values and methods so what is likely to dominate in 2015 is beginning to be taken somewhat seriously as the successor movement to our current fad with externally imposed managed care. Put another way, entire generations of people will resist new ideas, making implementation unlikely until their control fades and a new generation takes the helm. The exciting challenge for the observer is to address the issue of where health is and should be going. Both are difficult challenges. Agreeing on what is important and what is not represents a competitive challenge. How do we perceive the world? Surely our value sets will color what we see. Who is not predisposed to select a future where they fit and their pet theories are likely to become reality. For these and other reasons, it is probably easier to agree on what we would like to see happen in the future than on what is happening. Unfortunately, unless we see the world as it is, we are less likely to be able to shift it in a direction we would like to see.     

Health care technology--information technology/Part 4. Why will the Internet be important to clinicians?

As the popularity of the Internet's World Wide Web exploded in 1994 and 1995, corporations began adopting the browser software called Mosaic (and its derivatives) for their networks. Why? That same software can be used to "surf" the Internet. Since Intranets are easier to maintain and less expensive, they are replacing the more expensive "groupware" applications based on client-server architectures that corporations installed over the past five years. These Intranets are based on widely-available technologies designed for the Internet, not proprietary software designed for a relatively few customers. Organizations with communication networks integrated with their transaction systems and electronic medical records will be more effective in managing health care resources--and more attractive to employers and insurers for managed care contracting.     

Maternal employment in Scandinavia: a comparison of the after-birth employment activity of Norwegian and Swedish women

A striking characteristic of recent Western labour market trends is the rise in employment among mothers of very young children. So far, few studies have analysed the impact of public policies on employment rates of young mothers. In this study we address this issue by comparing two similar countries, Norway and Sweden, which have the same set of policies with slight variations, using data sets with similar designs. We analyse rates of re-entry into paid work after first birth for mothers in 1968–88 by means of hazard regression. One important finding is that the right to paid maternity leave with jobsecurity greatly speeds up the return to work.We want to thank Jan Kowalski for programming assistence and the Swedish Research Council for the Social Sciences and the Swedish Council for Research in the Humanities and Social Sciences for financial support for the Swedish study. We are grateful to John F. Ermisch, Siv Gustafsson, to two anonymous referees and to colleagues at the Demography Unit for valuable comments. Responsible editors. Siv S. Gustafsson, John F. Ermisch.