Knowledge that Transforms

Bartlett (1932) gave subjects a prose passage and showed how recall dropped when they were tested repeatedly. Ballard (1913), using poetry, and Erdelyi and Becker (1974), using pictures, reported improvements in performance (or hypermnesia) over repeated testing. We investigated two likely factors leading to the discrepant results: the type of material and the interval between tests. The primary cause of the differing outcomes is the interval between tests. In general, when the intervals between successive tests are short improvement occurs between tests. When these intervals are long, forgetting occurs. The type of material used plays little role: Hypermnesia in recall of prose (even “The War of the Ghosts”) occurred with short intervals between tests. We also report a striking confirmation of the power of tests to enhance memory: Repeated tests shortly after study greatly improved recall a week later.

We argue herein that typical training procedures are far from optimal. The goat of training in real-world settings is, or should be, to support two aspects of posttraining performance: (a) the level of performance in the long term and (b) the capability to transfer that training to related tasks and altered contexts. The implicit or explicit assumption of those persons responsible for training is that the procedures that enhance performance and speed improvement during training will necessarily achieve these two goals. However, a variety of experiments on motor and verbal learning indicate that this assumption is often incorrect. Manipulations that maximize performance during training can be detrimental in the long term; conversely, manipulations that degrade the speed of acquisition can support the long-term goals of training. The fact that there are parallel findings in the motor and verbal domains suggests that principles of considerable generality can be deduced to upgrade training procedures.

Human adults with normal vision, with three types of color-blindness, or with complete absence of vision since birth rank-ordered the similarities of all pairs of colors corresponding to nine hue names. When presented with the names only, subjects with any color vision produced rankings for which multidimensional scaling yielded Newton's color circle. When subjects were presented with the colors themselves, the recovered color circle remained the same for the normally sighted but collapsed along the red-green dimension for the color-blind. Based on their rankings by color names, the totally blind subjects all fell outside the range of the color-normal subjects but partly overlapped the color-deficient subjects; a rare rod monochromat roughly approximated the color-normal subjects. These results, along with those of Marmor (1978) and Izmailov and Sokolov (this issue), suggest how visual experience, language, and innate structure contribute to the mental representation of colors.

Because of its biological adaptive value, wariness of heights is widely believed to be innate or under maturational control. In this report, we present evidence contrary to this hypothesis, and show the importance of locomotor experience for emotional development. Four studies bearing on this conclusion have shown that (1) when age is held constant, locomotor experience accounts for wariness of heights; (2) “artificial” experience locomoting in a walker generates evidence of wariness of heights; (3) an orthopedically handicapped infant tested longitudinally did not show wariness of heights so long as he had no locomotor experience; and (4) regardless of the age when infants begin to crawl, it is the duration of locomotor experience and not age that predicts avoidance of heights. These findings suggest that when infants begin to crawl, experiences generated by locomotion make possible the development of wariness of heights.

One of the basic axioms of the rational theory of decision under uncertainty is Savage's (1954) sure-thing principle (STP) It states that if prospect x is preferred to y knowing that Event A occurred, and if x is preferred to y knowing that A did not occur, then x should be preferred to y even when it is not known whether A occurred We present examples in which the decision maker has good reasons for accepting x if A occurs, and different reasons for accepting x if A does not occur Not knowing whether or not A occurs, however, the decision maker may lack a clear reason for accepting x and may opt for another option We suggest that, in the presence of uncertainty, people are often reluctant to think through the implications of each outcome and, as a result, may violate STP This interpretation is supported by the observation that STP is satisfied when people are made aware of their preferences given each outcome

The cognitive “revolution” in psychology introduced a new concept of explanation and somewhat novel methods of gathering and interpreting evidence. These innovations assume that it is essential to explain complex phenomena at several levels, symbolic as well as physiological; complementary, not competitive. As with the other sciences, such complementarity makes possible a comprehensive and unified experimental psychology. Contemporary cognitive psychology also introduced complementarity of another kind, drawing upon, and drawing together, both the behaviorist and the Gestalt traditions.

The technology S‐curve is a useful framework describing the substitution of new for old technologies at the industry level. In this paper I use information from the technological history of the disk drive industry to examine the usefulness of the S‐curve framework for managers at the firm level in planning for new technology development. Because improvements in over‐all disk drive product performance result from the interaction of improved component technologies and new architectural technologies, each of these must be monitored and managed. This paper focuses on component technology S‐curves, and a subsequent paper, also published in this issue of the journal, examines architectural technology Scurves. Improvement in individual components followed S‐curve patterns, but I show that the flattening of S‐curves is a firm‐specific, rather than uniform industry phenomenon. Lack of progress in conventional technologies may be the result, rather than the stimulus, of a forecast that the conventional technology is maturing, and some firms demonstrated the ability to wring far greater levels of performance from existing component technologies than other firms. Attacking entrant firms evidenced a distinct disadvantage versus incumbent firms in developing and using new component technologies. Firms pursuing aggressive Scurve switching strategies in component technology development gained no strategic advantage over firms whose strategies focused on extending the life of established component technologies.