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931.
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
932.
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
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936.
Il est depuis longtemps reconnu que la vie affective de l'homme normal subit, surtout pendant l'enfance, une sorte d'organisation résultant d'une suite de transformations. On n'a cependant pas pris la peine de formulaer exactement les observations faites, ni d'en interprêter les conséquences avant Kant et Herbart. Ceux-ci ont aussi attiré l'attention sur la question de la différence entre émotions et passions. 相似文献
937.
Roger E. Ulrich William C. Holz Nathan H. Azrin 《Journal of the experimental analysis of behavior》1964,7(2):129-133
The introduction of a warning signal preceding shocks greatly increased the effectiveness of avoidance responding. Periods of “warm-up” at the beginning of the session were eliminated, and the number of shocks received by the subjects was greatly reduced. With response-shock interval constant, response rate increased as the interval between the response and the onset of the warning signal was shortened. The response tended to occur shortly after the onset of the warning signal regardless of the duration of these “safe” periods. A greatly elevated response rate was maintained even when the duration of the safe period was reduced to 0.3 sec. Thus, the pre-shock signal obtained nearly exclusive control of the responding and overrode the usual “temporal discrimination” of the response-shock interval. 相似文献
938.
This investigation examined the effects of 3 item characteristics—the average number of words per item, within-scale variability in item length, and item “direction”—on internal consistency reliability and interitem correlation. In Study 1, we examined the effects of these variables on overall scale-level reliability using 444 subscales from 9 personality scales. In Study 2, we examined interitem correlation at the paired-item level using 477 nonredundant item pairs from 14 personality scales. Lower scale reliability was associated with more average words per item, greater within-scale variability in item length, and a greater percentage of reverse-keyed items. Similarly, smaller interitem correlations were associated with a greater degree of mismatch in item length between the paired items and with a mismatch (vs. match) in the items' respective “directions.” The pattern of results across both studies supports our notion that lower internal consistency results from increased context switching; that is, from the confusion that occurs when respondents must switch back and forth between the interpretive frames pertaining to short versus long items, or between items pertaining to one pole of a personality dimension and its “opposite” pole. Suggestions for maximizing the internal consistency of personality scales are proposed. 相似文献
939.
Carlos F. Aparicio William M. Baum Christine E. Hughes Raymond C. Pitts 《Journal of the experimental analysis of behavior》2016,105(2):322-337
Studies of choice holding food‐amount ratio constant while varying food‐rate ratio within sessions showed that local changes in preference depend on relative amount of food. The present study investigated whether sensitivity of choice to food‐rate ratio and sensitivity to food‐amount ratio are independent of one another when food‐rate ratios are varied across sessions and food‐amount ratios are varied within sessions. Food deliveries for rats’ presses on the left and right levers were scheduled according to three different food‐rate ratios of 1:1, 9:1, and 1:9; each food‐rate ratio lasted for 106 sessions and was arranged independently of seven food‐amount ratios (7:1, 6:2, 5:3, 4:4, 3:5, 2:6, and 1:7 food pellets) occurring within sessions in random sequence. Each amount ratio lasted for 10 food deliveries and was separated from another by a 60‐s blackout. Sensitivity to rate ratio was high (1.0) across food deliveries. Sensitivity to amount ratio was low when food rates were equal across alternatives, but was high when rate ratio and amount ratio opposed one another. When rate ratio and amount ratio went in the same direction, choice ratio reached an elevenfold limit which reduced sensitivity to approximately zero. We conclude that three factors affect sensitivity to amount: (1) the limit to preference, (2) the equal effect on preference of amounts greater than four pellets, and (3) the absence of differential effects of switches in amount in the equal‐rates (1:1) condition. Taken together, these findings indicate that rate and amount only sometimes combine independently as additive variables to determine preference when amount ratios vary frequently within sessions. 相似文献
940.
William Meredith‐Owen 《The Journal of analytical psychology》2016,61(5):565-566