Regression weights as a function of test length

A battery of pencil-and-paper tests is commonly used for predicting a single criterion. If the score on each test is the number of correct answers, the composite battery score would normally be the sum of the weighted test scores, where the weights are the raw score regression weights. Knowing the reliability of each test, it is possible to alter the lengths of the tests in a manner such that the weights will all be equal. The composite battery score would then simply be the total number of items answered correctly and scoring would be greatly simplified. Such simplification is particularly desirable where the volume of testing is large. Section I of the article outlines the procedure for altering the lengths of the tests, and Section II gives a proof of the method.     

The organization of rapid movement sequences as a function of sequence length

An experiment was performed to test the predictions made by the subprogram retrieval model (Sternberg et al. 1978) for the production of rapid movement sequences, and to search for the maximum number of elements that can be planned in advance of sequence execution. Subjects performed rapid sequences of 1 to 8 finger taps under both simple and choice RT conditions. Increasing sequence length had no effect on choice RT, but caused simple RT to increase nonlinearly, with the greatest effect between 1 and 3 taps. Intertap intervals did not increase as a function of sequence length. The sequences' timing and force patterns suggested that sequences up to 8 taps were organized as single performance units. The results indicate a fundamental difference between activating a plan for a single tap and a sequence plan in which several elements must be coordinated and timed. Increasing the number of elements beyond 3 does not necessarily add processing steps in the selection and activation of the sequence plan, at least for sequences involving the repetition of a simple element.     

Schedule-induced polydipsia as a function of fixed interval length

Rats were trained to bar-press for Noyes pellets on an FI schedule which was increased serially through several values from 2 sec to as high as 300 sec. Concurrently, water was freely available. As FI length was increased, the degree of polydipsia increased linearly to a maximum value.     

Stability of apparent vertical and ocular countertorsion as a function of lateral tilt

The discrimination of a single temporal discontinuity, or gap, within an auditory pulse train was studied as a function of the relative magnitude of the gap region to its immediately surrounding interpulse intervals (the near surround) and to interpulse intervals flanking the near surround (the far surround). Near-surround effects substantially outweigh far-surround effects.     

Flooding as a function of shock level and length of confinement

In a one-way avoidance learning situation with rats, response prevention trials facilitated extinction as an increasing function of the duration of the prevention interval for shock levels below 1.8 mA. For 1.8 mA, extinction was a nonmonotonic function of the response prevention interval, with 15- and 210-sec durations showing the most facilitation of extinction. For all response prevention intervals except 15 sec, trials to extinction was a direct function of shock level. For 15 sec, it was an inverse function of shock level. The unexpected interaction of shock level with prevention interval was explained by invoking the concept of relief.     

Effect of syllabic neighbourhood as a function of syllabic neighbour length

The concept of syllabic neighbours (words sharing the same first syllable) is central in the interpretive framework of syllabic effects in visual word recognition. However, the definition of this concept remains surprisingly vague, so it is not clear whether or not syllabic competition is driven by words of similar syllabic length. The present study aimed to refine the definition by investigating the effect of higher-frequency syllabic neighbourhood as a function of syllabic neighbour length (similar syllabic length to the target words vs. any syllabic length). In both standard and go/no-go lexical decision tasks, the data showed that increasing the number of higher-frequency syllabic neighbours had an influence only when this number was computed from words of the same syllabic length as the target. Syllabic neighbours may therefore be considered as words sharing the first syllable and the total number of syllables with the target. Implications for accounts of syllable neighbourhood effects are discussed.     

The subjective tempo difference between interaural and monaural sequences as a function of sequence length

Previous research has demonstrated that the subjective tempo of sequences of clicks that alternate between ears is slower than that of nonalternating sequences. Although the stimulus onset asynchronies (SOAs) between the clicks are the same in both conditions, their perceptual onset asynchronies (POAs) differ by 25 msec at all SOA values between 40 and 2,130 msec. It has been suggested that this subjective tempo difference originates only after a few clicks have been processed. The present study shows this not to be the case: The POA difference between interaural and monaural click sequences could also be established with sequences comprising only a few clicks.     

The apparent length of rotating arcs under conditions of dark adaptation

The apparent contraction of a rotating light arc occurred during the first 20 rain, but not after 25 min, of dark adaptation. Estimates of length obtained after 25 min were affected by the level of luminance of the arc but not by its speed of rotation, by dark gaps in the arc, or by instructions to estimate its length in terms of a brighter region. There was no tendency for a rotating dark arc to appear shorter at any stage of adaptation.     

Psychomotor reminiscence as a function of sex and length of rest period

Sex differences in psychomotor reminiscence were examined as a function of the length of the rest period. Five groups of Caucasian subjects, each group consisting of 12 males and 12 females, practiced continuously for 3 min on a mirror-tracking task, then rested for 0,1, 2, 4, or 8 min before resuming continuous practice. Reminiscence in both sexes increased as negatively accelerated functions of the amount of rest. The asymptotic level of reminiscence was higher for females than for males, but the quadratic slopes of the two functions were essentially alike. Analyses of prerest trial gains supported a conclusion that females reminisced more because they accumulated more reactive inhibition prior to rest.