Determinants of withdrawal behavior: An exploratory study

Research on college persistence has typically classified nonreturnees as dropouts. Recently, this practice has been criticized by Tinto (1987) who argues that such a practice merges together different types of withdrawal behavior whose determinants may vary as a function of the particular departure behavior under consideration. This paper empirically examines whether the determinants of decisions to withdraw from the institution are similar to those affecting decisions to transfer to other institutions of higher education for the 1984 entering freshman class at a large southern institution. Results provide support for Tinto's proposition of differentiating between different types of voluntary withdrawal behavior. While institutional commitment, academic performance, finance attitudes, and student perceptions of faculty concern for student development and teaching discriminated between persisters and dropouts, only final institutional commitment and final goal commitment discriminated between persisters and transfers.An earlier version of this paper was presented before the 1990 American Educational Research Association annual meeting.     

Early Relationship Quality From Home to School: A Longitudinal Study

The aim of this investigation was to examine the role of social relationships in the home as predictors of social functioning in the first years of school. Longitudinal data gathered on 156 children from urban, low-income families were used to examine the unique contributions of mother-child attachment classification at ages 1 and 2 years, the child's relationship with another adult caregiver, the child's closeness to a sibling, and the child's status in the family relative to siblings between ages 3 and 4 years, to teacher reports of their own relationship to the child and the child's social skills in the classroom and peer relations. The role of family-based relationships as possible protective factors for children at social or demographic risk for problems in school was also tested. Results indicate that quality of different family relationships provides relatively independent and complementary information about early social functioning in school, with more limited evidence for compensatory or protective processes at work.     

The US-preexposure effect in honeybees

Signaled avoidance was studied in individual honeybees that visited the laboratory regularly to take sucrose solution from a target set on the sill of an open window. During feeding, substrate vibration or airstream was used to signal a brief shock that could be avoided by breaking off contact with the food for a few seconds. Aversive conditioning of the context was measured in terms of return time (the time between successive visits). In Experiment 1, experience with unsignaled shock was found to lengthen return time—which experience with signaled shock did not—and to impair performance in subsequent avoidance training with signaled shock (the US-preexposure effect). In Experiment 2, experience with unsignaled shock given after signaled avoidance training lengthened return time but had no effect on response to the signal in a subsequent extinction test. These results closely resemble the results obtained in analogous experiments with vertebrates.     

Using New Proximity Measures With Hierarchical Cluster Analysis to Detect Multidimensionality

A new approach for partitioning test items into dimensionally distinct item clusters is introduced. The core of the approach is a new item-pair conditional-covariance-based proximity measure that can be used with hierarchical cluster analysis. An extensive simulation study designed to test the limits of the approach indicates that when approximate simple structure holds, the procedure can correctly partition the test into dimensionally homogeneous item clusters even for very high correlations between the latent dimensions. In particular, the procedure can correctly classify (on average) over 90% of the items for correlations as high as .9. The cooperative role that the procedure can play when used in conjunction with other dimensionality assessment procedures is discussed.     

The dynamics of the impact and coalescence of droplets on a solid surface

A simple experimental setup to study the impact and coalescence of deposited droplets is described. Droplet impact and coalescence have been investigated by high-speed particle image velocimetry. Velocity fields near the liquid-substrate interface have been observed for the impact and coalescence of 2.4 mm diameter droplets of glycerol∕water striking a flat transparent substrate in air. The experimental arrangement images the internal flow in the droplets from below the substrate with a high-speed camera and continuous laser illumination. Experimental results are in the form of digital images that are processed by particle image velocimetry and image processing algorithms to obtain velocity fields, droplet geometries, and contact line positions. Experimental results are compared with numerical simulations by the lattice Boltzmann method.     

Promoting secondary school students’ evaluation of source features of multiple documents

The current research examined whether instructional activities centering on contrasting cases promoted secondary school students’ evaluations of source features present in a multiple-documents inquiry context. Two hypothetical students’ document evaluation strategy protocols were designed: One featured more sophisticated strategies commonly enacted by experts and better college students and a second featured less sophisticated strategies commonly enacted by secondary school students. A series of classroom-based activities required that students compare/contrast the two protocols to decide which were the best strategies when analyzing multiple scientific documents and why. The findings demonstrated that students who previously participated in the intervention activities included more scientific concepts from more useful documents when generating essay responses from memory, displayed better rankings of the usefulness of the set of multiple documents, and offered more principled justifications based on source feature evaluations of trustworthiness compared to students who instead received typical classroom instruction. We discuss the instructional implications of a contrasting-cases approach in facilitating secondary school students’ usage of source features within multiple-documents inquiry contexts.     

The system of intellectual support for making decisions by planning and training

The paper is devoted to the problem of the qualitative training of management specialists. New methods and instruments permitting the quality of accepted decisions to be heightened are described. It is suggested to use an SISDM containing the functions of the system as an instrument for planning decisions and training in decision making with the use of computerized methods for the active teaching of the method for the analysis of concrete situations and management games.     

A systematic approach to analysing sports performance

A systematic approach to the analysis of sporting events is discussed. The basic tenet is that objective quantification of critical events is required for a complete analysis. This approach encompasses diverse areas of methodology and research, such as quantification, biomechanics and physiology. The theoretical underpinning are behavioural, in so far as athletes produce observable behaviour that can be quantified and ultimately changed. Several areas of analysis are linked together in a general framework and each one of these areas is dealt with in detail.