A modular synthesis of functionalized carbocyclic propellanes was developed. Formation of the first of two quaternary bridgehead centers has been achieved by desymmetrization of prostereogenic ketones by either Hajos-Parrish-Eder-Sauer-Wiechert-type processes or Werner's catalytic asymmetric Wittig reaction. The obtained bicyclic enones were subjected to conjugate additions upon which the remaining ring was formed by olefin metathesis. All bridges are amenable to further derivatization, which renders those compounds useful as central units in fragment-based drug discovery or as ligand scaffolds.

Although geometric analogies are popular items for measuring intelligence, the information processes that are involved in their solution have not been studied in a test theory context. In the current study, processing is examined by testing alternative models of information structure on geometric analogies. In contrast to the treatment of models in other studies that have appeared in the cognitive literature, the models are tested jointly as mathematical models of processing and as latent trait models of individual differences. The joint model-ing was achieved by applying the one-parameter linear logistic latent trait model to predict response accuracy from information structure. The results supported the model that distinguished between spatial distortion and spatial displacement transformations, which have opposite effects on item difficulty. Further, no significant sex difference in overall accuracy or processing were observed. Implications of the results for processing mechanisms and test design are discussed. Geometric analogies are popular items for measuring nonverbal intelligence. They are included on tests such as the Cognitive Abilities Test (CAT), the Lorge-Thorndike Intelligence Test, and the American Council on Education Examination (ACE). An example of a geometric analogy that is similar to CAT items is given in Figure 1, along with structural notation. The task is to select from the alternatives (D1 to Ðs) to find a figure that is related to C in the same way that B is related to A.Similar to most types of intelligence test items, validation studies on geometric analogies have been mainly concerned with trait organization rather than the nature of processing involved in item performance. That is, person scores are correlated with other tests or achievement and learning, but studies of processing are infrequently reported. Thus, the psychometric validation research has not clarified the nature of the reasoning process measured by geometric analogies.A new type of validity research, cognitive component analysis of aptitude (e.g., Pellegrino & Glaser, 1979; Sternberg, 1977a; Whitely, in press), seeks to understand test validity by identifying the information processes that contribute to performance. Cognitive component analysis has been applied to several types of aptitude test items, including verbal analogies (

This study examines the influence of processing strategies, and the associated metacomponents that determine when to apply them, on the construct validity of a verbal reasoning test. Three strategies for solving verbal analogy items were examined: a rule-oriented strategy, an association strategy, and a partial rule strategy. Construct validity was studied in two separate stages: construct representation and nomothetic span. For construct representation, evidence was obtained that all three strategies, and their related metacomponents, are associated with performance on analogy items. For nomothetic span, the current study found that all three strategies contribute to individual differences in verbal reasoning and to the predictive validity of the test. The results of this study also point to the utility of metacomponents as constructs for describing and understanding test performance. Implications of the results for test development and theories of aptitude are elaborated.

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