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891.
Considered in this paper is a decision task which has been employed to study multistage betting behavior. When the task commences, a decision maker (DM) is provided with some capital x (x > 0) which he is required to allocate over m (m > 1) mutually exclusive and collectively exhaustive alternatives, each of which occurs with probability pi (pi > 0, i = 1,…, m; Σi=1mpi = 1). If the amount yi is allocated to alternative i (yi ≥ 0, Σi=1myi = x) and alternative i obtains, DM's capital for the next stage of the game becomes yiri, where ri (ri > 0) is the return per unit allocated to alternative i. The task consists of N stages.Defining risk in terms of the mean and variance of DM's bets, and assuming that the minimization of risk is DM's objective, decision policies satisfying this objective are derived in closed form and their testable properties are briefly discussed. 相似文献
892.
Chester A Insko Elaine Songer William McGarvey 《Journal of experimental social psychology》1974,10(1):53-83
It was argued that Heider's p?o?x triad can best be conceptualized according to a three- factor analysis of variance model in which the p?o, p?x, and o?x bands are all factors. From this perspective the balance effect is the triple interaction, the positivity effect a main effect for the p?o factor, and the agreement effect a p?x by o?x interaction. Although the existence of the latter two effects has previously been regarded as damaging to balance theory, it was shown that these effects could be interpreted from a balance perspective and that balance theory could be used to generate supportable propositions regarding these effects. Thus in agreement with a unit-relation interpretation it was shown, in accordance with balance theory, that positivity effects are obtained when the subject, or p, assumes future contact with o, that reverse positivity effects are obtained when the subject anticipates breaking off contact with o, and that no positivity effect is obtained when there is absolutely no contact, past or future. It was also demonstrated in an experiment involving the p?o?q triad that, in accordance with balance theory, positivity effects may be produced by the assumption or inference of same-sign reciprocation in sentiment. Evidence for two balance processes underlying agreement effects was also found. One of these processes was based on the assumption that the subject would have or reveal psycho-logical reasons for the disagreement and thus produce imbalance. Consistent with this interpretation it was found that the agreement effect was significantly larger when future contact with discussion of x was assumed than when future contact without discussion of x was assumed. The other, or unit-relation interpretation was supported by evidence indicating that the breaking off of contact resulted in a reversed agreement effect. In general, it was argued that balance theory did quite well in such phenomenological investigations when attention was not narrowly restricted to the three-sign pattern but considered other potential cognitive bands. 相似文献
893.
Instrumental licking of .4% saccharin solution was increased by the contingent opportunity to lick a less-preferred saccharin solution when the contingency schedule deprived the subject of the contingent response, but not otherwise. Schedules that imposed comparable amounts of response deprivation produced comparable increases in instrumental responding. The results support the hypothesis that instrumental responding will increase if and only if the contingency schedule deprives the subject of the contingent response. They also support the implication that the predicted increase will occur even if the contingent response has a lower operant level than the instrumental response. 相似文献
894.
William P. Dunlap Larry F. Hughes Lawrence DachowskiThomas J. O'Brien 《Learning and motivation》1974,5(4):484-497
General activity subsequent to reward (R) and nonreward (N) was monitored at 5-sec intervals with a stabilimeter in the runway goal box. Activity of never-rewarded control Ss was also measured. In Expt 1 it was found that the frustration effect (difference between N- and R-trial activities) disappeared after about 40 sec of goal box confinement. This disappearance of the frustration effect was due to activity increase on R trials rather than activity decrease on N trials as a function of time. Comparison of N-trial activity with control group activity indicated that frustration does not dissipate within 60 sec. Expt 2 investigated activity following reward and nonreward as a function of reward magnitude. Evidence from these experiments suggests that the late R-trial activity increase results from frustration, possibly conditioned to apparatus cues on N trials. 相似文献
895.
The Ss made judgments of the frontoparallel plane monocularly and binocularly by adjusting the position of a rotatable thin luminous line viewed in darkness. The judgments were made before and after a 10-min period of monocular inspection of a luminous outline frontoparallel trapezoid which was the projection of a rectangle rotated in depth. Verbal reports indicated normalization of perspectival slant depth, i.e., the inspection figure appeared less rotated, and the line settings exhibited an aftereffect bf normalization. These findings may contribute toward an account of certain previously unexplained observations reported in an earlier study by Epstein and Morgan-Paap (1974) dealing with adaptation to uniocular image magnification. 相似文献
896.
William E. Cooper 《Attention, perception & psychophysics》1974,16(2):229-234
Selective adaptation experiments were conducted to test for the presence of a mechanism that mediates an aspect of both speech perception and speech production. Ss were instructed to utter /i/ or /bi/ after listening to repetitions of either of these syllables or to repetitions of the vowel /i/. Analysis of the utterances showed that a timing relation which distinguishes /pi/from /bi/, namely the latency in onset of voicing relative to the release burst of the consonant, varied systematically for the /pi/ utterances but not for the /bi/ utterances as a function of the speech input. The effect for the /pi/ utterances was shown not to be attributable to factors such as compensation for distorted perception of the /pi/ adapting stimulus or voluntary mimicry of this stimulus. 相似文献
897.
Analysis of variance and uncertainty analysis are analogous techniques for partitioning variability. In both analyses negative interaction terms due to negative covariance terms that appear when non-orthogonal predictor variables are allowed may occur. Uncertainties can be estimated directly from variances if the form of distribution is assumed. The decision as to which of the techniques to use depends partly on the properties of the criterion variable. Only uncertainty analysis may be used with a non-metric criterion. Since uncertainties are dimensionless (using no metric), however, uncertainty analysis has a generality which may make it useful even when variances can be computed.The work of the senior author was supported by Contract N5ori-166, Task Order 1, between the U.S. Office of Naval Research and The Johns Hopkins University. This is Report No. 166-I-192, Project Designation No. NR 145-089, under that contract. 相似文献
898.
William H. Angoff 《Psychometrika》1956,21(3):295-297
A method is provided for estimating the nonspurious correlation of a part of a test with the total test. Two cases are considered: one in which the actual subtest is parallel to the total test, the other in which the actual subtest is not parallel to the total test. 相似文献
899.
900.