Thesis (M.S.)--University of Michigan, 1991.

Thesis (M.S.)--University of Michigan, 1987.

Thesis (M.S.)--University of Michigan, 1991.

Thesis (doctoral)--Göteborg University, 1997. / Added t.p. with thesis statement inserted.

Thesis (doctoral)--Göteborg University, 1997. / Added t.p. with thesis statement inserted.

The present study was a systematic investigation of hierarchical skill sequences in the design copying domain. The factors associated with possible variations in task difficulty were delineated. Five hierarchies were developed to reflect variations in rule usage, the structuring of responses, presence of angles, spatial orientations, and stimulus complexity. Three-hundred thirty four subjects aged five through ten years were administered a 25 item design copying test. The data were analyzed using probabilistic models. Latent trait models were developed to test the hypothesized skill sequences. Each latent trait model was statistically compared to alternate models to arrive at a preferred model that would adequately represent the data. Results suggested that items with predictable difficulty levels can be developed in this domain based on an analysis of stimulus dimensions and the use of rules for task completion. The inclusion of visual cues to guide design copying assists accurate task completion. Implications of the current findings for facilitating the construction of tests which accurately provide information about children's skill levels were discussed. The presence of hierarchical skill sequences in a variety of ability domains was supported.

This investigation was designed to test a hypothesis formulated by Julia Sherman (1967) concerning the development of spatial visualization and mathematic skills. The intention of the study was to examine the influence of early physical training on spatial visualization and mathematic skills, to determine whether intensive training in spatial relations would have a differential impact on male/female spatial performance and to gather information concerning the relationship between spatial visualization and mathematic performance. The investigation was divided into three studies and used 166 college students as subjects. Study one examined the impact of long term physical training, gymnastics, on spatial visualization and mathematic scores of two matched-groups selected from 99 subjects. The two groups, gymnast and control, each consisted of 28 subjects (14 males and 14 females) and were matched on IQ score, age, ethnic group, socioeconomic status, parental and sex-role identification, achievement motivation and years of training in other sports. Gymnasts averaged 5.5 years of gymnastic training: the control group had none. Study two examined spatial visualization scores obtained by 67 architectural students (49 males and 18 females) before and after a semester's training in spatial relations. Study three compared scores obtained by all 166 subjects on the Shepard Metzler Mental Rotation Test and a mathematic test derived from the Otis Test of Mental Abilities. The test of the hypothesis relating to the influence of early physical training on spatial and mathematic performance was not successful as the training of the gymnasts did not extend to early childhood. While significant sex-related differences favoring males were found in spatial performance, the amount of variance in spatial scores accounted for by sex was small, only 8%. No significant sex-related differences in mathematic performance were found. In study two, both males and females significantly improved spatial performance following training, but females did not demonstrate a significantly greater rate of improvement as predicted. The results of the third study indicated a moderate positive relationship between spatial and mathematic performance, however, no evidence was found to support a direct causal relationship between spatial skill and mathematic performance.

published_or_final_version / Psychology / Master / Master of Philosophy

This research investigated the precision with which spatial information can be maintained in memory and reproduced as well as factors which may effect these emerging abilities. To study this, ten males and ten females in each of first, third, fifth, and seventh grades participated in three drawing tasks under two conditions (match and recall). The tasks involved the presentation of a 4" straight line or a 2" x 2" right angle drawn on an 8" white disc. Subjects were asked to draw a line exactly the same size and in the same place (static), after an imagined rotation, or after an imagined bending or unbending of the line (transformation) on an 1" white disc. Several mixed design analyses of variance with repeated measures on the task variables were run. First graders made significantly more errors than all other subjects. Third and fifth graders differed little and both performed significantly less accurately than seventh graders. Performance on the rotation task and the transformation task did not differ significantly with performance on both yielding more error than performance on the static task. The match condition generally proved easier than the recall condition, straight lines led to less error than bent lines, and orientation information was more accurately preserved than metric information. The requirements of the task, i.e., no change, change in position, or a change in form, interacted with both the stimulus type and the type of information preserved. Grade level also interacted significantly with task and stimulus type. When determining how spatial abilities emerge and the accuracy with which spatial information can be dealt, task demands, stimulus characteristics, and type of information being measured must be considered along with the developmental changes.

The search for evidence of cognitive abilities in young children that have been previously detected only in the performance of older children and adults has been a target of study by many cognitive developmental psychologists. Early competency views suggest that aspects of cognitive fundamentals are present very early in life and are in some aspects developmentally invariant. Often, the focus of research is on the delineation of the constraints which direct and restrict deployment of early intellectual abilities to illuminate the regularities and patterns in observed developmental change. The purpose of this research was to examine children's proficiency with mental rotation tasks that involved the reorientation of complex multi-component stimuli. Specifically, the existence of stimulus effect and determination of which stimulus components prove problematic under taxing performance conditions was investigated. Sixteen students, eight first graders and eight third graders, participated in a two-choice discrimination task. Each student was assessed individually on 360 test trials in eight 20-minute sessions. Three test conditions included (1) perception, (2) memory, and (3) rotation. Two multi-component stimuli were used in which the experimenter-defined components included (A) an external protrusion on the edge of a circle, and (B) an internal axis system within the interior of the circle. The two stimuli varied in the placement of the internal axes which was either orthogonally or obliquely orientated. Test items in the memory and the rotation conditions included stimuli orthogonally oriented (90°, 180°, 270°) obliquely oriented (45°, 135°, 225°, 315°). Error scores were analyzed in a four-way analysis of variance. A main effect for foil type was found significant with axis foils being more difficult than protrusion foils. Furthermore, a significant four-way interaction effect was detected indicating that as stimulus characteristics and task demands increased in difficulty, performance declined particularly for the younger age group.