A comparison of four methods of constructing factor scores

Four least-squares methods for constructing factor scores have been described in the literature. The formal properties of these scores are developed, and they are compared in terms of four generally desirable properties of constructed factor scores. In particular, it is shown that two of the methods yield scores that are conditionally unbiassed, and univocal in the sense of Guilford and Michael, though not orthogonal, while one of the other methods yields orthogonal scores.It is shown that constructed factor scores cannot be simultaneously univocal and orthogonal, unless we choose the special basis in factor space given by Canonical Factor Analysis.The general problem of choosing between the methods is discussed, on the basis of the theoretical relations obtained.EDITOR'S NOTE: The reader will quickly discover that this article develops several of the generalizations given in the second part of the preceding article, On Factors and Factor Scores. Independent development of the same generalizations is, of course, not a new phenomenon. Because the Presidential Address automatically is accepted for publication and given space in the December issue, it was decided that the only fair thing to do was to print this article in the same issue.     

Training of fast tapping with reduction of kinaesthetic, tactile, visual and auditory sensations

Five subjects were trained to tap on a light Morse-key during nerve compression block. The training sessions lasted for 40 sec., with a 5 sec. rest after the first 20 sec. work period. The group learning curve reached 89.5 per cent. level of normal performance by the eighth training session. In the ninth, the testing session, subjects tapped with visual and auditory sense reduction superimposed on the kinaesthetic and tactile impariment of the training condition. Performance in the testing session reached 40.9 per cent. of normal.

The sixth subject was trained in the same task as the other five subjects, but the training condition included elimination of cues from all four sensory channels. He reached 79.09 per cent. of his normal tapping performance in the seventh session.

These results show that the motor skill of tapping can be relearned in the absence of kinaesthetic cues. Furthermore when the subject has no conscious knowledge of any peripheral sensory cues connected with the ongoing motor activity, learning can nevertheless take place. These findings lead to the hypothesis, that skilled motor activity can be monitored by central processes alone.

During the training sessions subjects showed a tendency of tapping in groups of gradually increasing length. It is hypothesized that increased number of taps forming a group gives an indication to the possible mode of action of these central processes.     

The functional architecture of instrumental conditional reflexes

The author holds the opinion that the so-called operant, or instrumental, conditional reflexes, in spite of differences in specific features, do not differ in principle from classical conditional reflexes, and therefore they should not be opposed to them, or be placed in a special or separate group. In support of this opinion, this paper presents data which show that:

1. 1.
   In the establishment of classical and operant conditional reflexes, two-way conditional connections—direct and reverse—are formed.     

The effect of angle between the oblique lines on the decrement of the Müller-Lyer illusion with extended practice

Early work on the Müller-Lyer illusion had indicated that it disappears with extended practice. The present experiment failed to confirm this finding. The magnitude of the illusion decreased for approximately 500 trials, but showed no further change over an additional 500 trials. The rate of the practice decrement was inversely related to the size of the angle formed by the oblique lines of the figure.     

Population norms of top sensory magnitudes and S. S. Stevens’ exponents

If S. S. Stevens’ exponents indicate the rates at which sensations grow with increases in sensory intensity, they ought to correlate with the population norms of top sensory magnitudes. Using a comprehensive sample of eight sensory dimensions, the tau coefficient of rank correlation between Stevens’ exponents and the medians of the top sensory magnitudes reported by 305 observers was found to be only +.15 (p>05). With the geometric means tau fell to ?.04. A split-half consistency check on the medians of the population norms suggested that they were not to blame for the low correlation. Direct comparisons of pairs of sensory dimensions on 146 additional observers produced results which confirmed the population norms. Since there is no way of comparing most of the top physical stimuli experienced in everyday life, it is not possible to make a joint prediction from exponents and top stimuli. S. S. Stevens’ exponents thus appear to have little predictive value outside the experimental conditions under which they were measured.     

BRIDGING PHYSIOLOGY AND PHENOMENOLOGY IN DYNAMIC PSYCHOLOGY

R asmussen , E. T ranekjær . Bridging physiology and phenomenology in dynamic psychology. Scand. J. Psychol ., 1961, 2, 161–166.—It is important to distinguish between the immediately experienced (the phenomenological) and the physiological-neurological basis for the phenomenological world, e.g. between beta needs (subjectively experienced states of needing or wanting) and alpha needs (objectively defined, physiological needs). The concept of psychon is introduced and defined as a necessary and sufficient condition in the physiological-neurological system for the existence of a subjective experience; psychon bridges the gap between the physiological and the phenomenological world.