Prediction of Chaotic Time Series in the Presence of Measurement Error: the Importance of Initial Conditions

In this paper we argue that even if a dynamic relationship can be well described by a deterministic system, retrieving this relationship from an empirical time series has to take into account some, although possibly very small measurement error in the observations. Therefore, measuring the initial conditions for prediction may become much more difficult since one now has a combination of deterministic and stochastic elements. We introduce a partial smoothing estimator for estimating the unobserved initial conditions. We will show that this estimator allows to reduce the effects of measurement error for predictions although the reduction may be small in the presence of strong chaotic dynamics. This will be illustrated using the logistic map.     

A sociometric status index without subgroup membership bias

Sociometric status is a widely used indicator to assess what is called popularity of a person within a group. The purpose of this paper is to show that status as defined by known indices may be biased whenever there are subgroups unequal in size within the total group and within-group choices are more probable than between-group choices. The problem of subgroup membership bias may be solved, however, by a simple linear transformation.     

Suicide in Adolescent American Indians: Preventative Social Work Programs

Suicide is a leading social problem among the adolescent American Indian community. This literature review examines the demographics of American Indian adolescents who attempt suicide, along with the effects it has on the entire family/community. This paper describes various programs used to address individuals, while correlating them to specific use within the American Indian population. The authors look at the effectiveness of the Adolescent Suicide Prevention Project, American Indian Life Skills Development Curriculum, and Zuni Life Skills Development, along with the draw-backs associated with the implementation of each program. The importance of incorporating culturally specific programs and addressing the issue at a community level in an attempt to enhance the well-being of at-risk American Indian Adolescents is emphasized.     

Postmodern‐oriented practices and patient‐focused research: possibilities and hazards

In this article two streams of thought within family therapy, one representing a traditional research focus and the other postmodern oriented practices are brought together. A qualitative study is described that used standardised measures to monitor therapeutic practice and provide feedback on process and outcome to therapists. The opportunities and pitfalls concerning this approach are discussed and illustrated. The use of measures as conversational tools increases and expands opportunities for collaboration between children, parents and their therapists. However, in organisations these measures risk becoming tools of competition instead of conversation, which is helped when managers take responsibility for implementing and supporting a culture of feedback.