Showing papers by "Wolfgang Wagner published in 1989"

A new method for optimizing the structure of thermodynamic correlation equations

Abstract: An optimization strategy is presented for optimizing the structure of empirical thermodynamic correlation equations. Based on a comprehensive functional expression for the physical dependence considered, which is called a “bank of terms,” the new procedure optimizes the structure and the length of the equation as well. The application of this method results in an equation which meets the quality wanted for representing the experimental data with the lowest number of fitted coefficients. The procedure can be used for the determination of the structure of any equation where the method of the linear least squares is applicable. A detailed description of the algorithm is given which includes values for the control parameters for different applications in the field of thermodynamics (vapor pressure equations, equations of state, etc.) and also for applications in other fields. The optimization steps are described using an equation which represents a relationship between variables in a general form. It is demonstrated how even the complex problem of the optimization of a fundamental equation for the Heimholtz energy can be written in terms of this general equation.

Origins of the misplaced confidence effect in collaborative recall

Abstract: Studies have shown that dyads and groups place significantly more confidence in wrong answers to questions about a jointly witnessed event than do individuals. This experiment was designed to discover whether this misplaced confidence is influenced by prior free collaborative recall of the events in question. The results clearly indicated that prior group remembering lessens the effect, and improves the testimonial validity of both individual and group answers to questions about a jointly witnessed event. Taken in conjunction with other studies, the results imply that two or more witnesses of an event may profitably discuss what happened, but that they may best be interrogated separately in order to maximize the information available to the interrogator and to minimize misplaced confidence. Language: en

Findings significant with respect to short- and medium-term outcome in schizophrenia--a preliminary report.

Abstract: 1. The objective of the study was to determine the relationship of psychopathological, psychobiological, and clinical psychological variables to short- and medium-term outcome in schizophrenia. 2. The predictive power of several variables described as potential predictors in the literature were evaluated. To these we added clinical psychological variables; most of these had never been examined in a prospective study. 3. The sample consisted of a total of 45 patients. None of the patients was on medication and all were tested shortly after admission to the hospital. The following factors were regarded as outcome criteria: change in the GAS-score four weeks after admission, length of hospitalization after index admission, relapse nine months after admission and two years after discharge. 4. We found that the psychobiological data set as well as the clinical psychological data set had the highest predictive power with respect to short- and medium-term outcome. 5. An analysis of the single variables within the clinical psychological data set revealed that the patients with attention disorder and a low Stimulus Barrier Function (Bellak-scale) responded better to a four-week Haloperidol treatment. Patients with a low Stimulus Barrier Function at admission had, in comparison to this, a poor outcome after two years (relapse). (No patient was taking drugs regularly at this time.) The expressed emotion of the relative approached only significance (p < .07) as a factor to be connected with relapse after two years. 6. As psychobiological factors the ANS activity and the CT were measured. The latter in order to evaluate possible atrophie alterations in the brain. 7. Higher activity of the ANS was found in those patients who were hospitalized for a longer period. Slight atrophie alterations of the brain (CT scan) were related to poor outcome after two years (relapse). 8. No significant relationship was found between the psychopathological state at admission and short- or medium-term course of the illness. 9. The findings are Interpreted as showing the importance of psychobiological as well as clinical psychological variables in order to uncover the factors related to the heterogeneous course of the schizophrenic illness.