Experimental design symbolization and model derivation

A method of design symbolization (DS) is given for a class of designs in which all factors are related by complete crossing or by nesting. Characterization of acceptable DS's, and logical relational properties are given. It is shown how the design model can be obtained from the DS.The preparation of this article was supported by NIH Grant GM-11128, and by grants to the Institute of Human Learning by NSF and NIH.     

Factor analysis by minimizing residuals (minres)

This paper is addressed to the classical problem of estimating factor loadings under the condition that the sum of squares of off-diagonal residuals be minimized. Communalities consistent with this criterion are produced as a by-product. The experimental work included several alternative algorithms before a highly efficient method was developed. The final procedure is illustrated with a numerical example. Some relationships of minres to principal-factor analysis and maximum-likelihood factor estimates are discussed, and several unresolved problems are pointed out.The authors wish to thank the Factor Analysis Work Group (supported, in part, by ONR) for valuable criticisms and suggestions made in the course of a discussion of the present work in April, 1965.     

Short-term recognition memory for single letters and phonemic similarity of retroactive interference

Copying 12 letters produces more retroactive interference in recognition memory for a single letter when the interference letters possess a vowel sound in common with the letter to be remembered than when they do not. Compared to interference lists that do not include the presented letter, inclusion in the interference list of the letter to be remembered improves recognition memory when the other interference letters have no vowel sound in common with the letter to be remembered, but not otherwise. False recognition rates are greater when the test letter contains a vowel sound in common with the presented letter than when the vowel sounds of these two letters are different. The findings are in complete accord with analogous findings for short-term recall and indicate that short-term recognition memory uses the same phonemic-associative memory system as short-term recall.     

Source variability and recall of auditory material 1

Recall of auditory narrative material was measured under three conditions of presentation. These were a single source condition with material from one speaker, a four source fixed sequence condition with material from four speakers in a fixed sequence of 3-sec. lengths, and a four source random condition with material from four speakers in a random sequence of 3-sec. lengths. Recall was better for the single source condition than for the four source conditions. No significant difference was found between the fixed and random sequential presentations. Results are discussed in terms of the attentional behaviors involved in the tasks.     

STUDIES IN THE PSYCHOLOGICAL EFFECTS OF A NEW DRUG (DIETHYLPROPION): Subjective effects in the natural environment

Two doses diethylpropion, one dose pipradrol, one dose amobarbital and placebo were administered to 116 subjects, who rated their state on twenty variables. The variables were intercorrelated under pipradrol and pentymal. The correlation matrices were subjected to factor analysis. Four factors were found in both studies: Happiness, Alertness, Relaxation, and Flight of thoughts. There is some agreement between the two factor analyses. There were few significant effects of the drugs on factor scores, but the structure is quite unambiguous: pipradrol and diethylpropion are stimulating, and amobarbital tranquilizing.     

Information processing,neuropsychological function,and the inherited predisposition to alcoholism

Sons of male alcoholics are at particularly heightened risk for the development of alcoholism. This heightened risk frequently appears in association with increased incidence of conduct disorder or hyperactivity, with deficits in abstract thinking and poor school performance, with abnormalities in cued psychophysiological response, and with increased sensitivity to the putatively stress-response-dampening effects of alcohol intoxication. This risk and its associated features are discussed within the context of a neuropsychological theory, predicated on the notions (1) that deficits in cognitive functions theoretically dependent upon the intact functioning of the prefrontal cortex could underlie manifestation of the idiosyncracies commonly attributed to sons of male alcoholics, and (2) that acute alcohol intoxication could relieve the subjective discomfort associated with the consequences of such deficits.