James Rotton

Power Tables for Analysis of Variance.

In numerous applications of the analysis of variance it is necessary to compute the power of F tests having numerically high alpha (significance) levels. This article tabulates the power of F tests for numerator degrees of freedom, df = 1, 2, 3, 6, 9, 12; denominator df = 3, 6, 9, 12, 15, 20, 40, 60, 120; alternative hypotheses, phi = 2.(.2)3.0; and significance levels, alpha = .05, .10(.10),.50. The use of these tables is illustrated with a brief numerical example.

Dogmatism, Trust, and Message Acceptance

Summary Forty-eight high and 48 low dogmatic undergraduates were led to expect positive, neutral, or negative information about unidentified foreign nations, but along with a no-expectancy control group (n # 24) they received only neutral information. As hypothesized, low dogmatic (open-minded) persons were unaffected by the prior pronouncements of a source, but closed-minded (dogmatic) individuals rejected both source and message when their expectancies were disconfirmed. It was concluded that openminded persons attended to the content and implications of a message, whereas closed-minded persons attended to the surface quality of information and the reputation of the source.

Normative Ratings of National Attributes

301 college students rated 39 country names and 345 characteristics of foreign nations as to attractiveness, believability, importance, and clarity. A number of the normative values of the national attributes were tabulated. Varied groups of studenrs perceived the statements in a highly reliable manner; attractiveness, clarity, and importance ratings proved very stable over time, while believability ratings were less so. The relevance of the national attributes to information integration, impression formation, and artitude change studies was discussed.

Confidence in information: Source and dogmatism effects☆

Abstract Forty-eight high and forty-eight low dogmatic subjects received neutral information about fictitious countries from sources who were positive, unbiased (neutral) or negative toward the country. Dogmatic persons had most confidence when they were given information that was consistent, either internally or over time. Open-minded persons placed most confidence in information when it came from a source that had previously been more favorable than his current pronouncements; they had little confidence in large amounts of (internally) consistent material. It was concluded that closed-minded people react to surface indicators of validity (consistency, amount of information) whereas open-minded people use the characteristics of a description (“shift toward negative”, distrust of over consistency), to make inferences about a communicator.

TEST OF TWO MODELS FOR ACQUISITION OF INFORMATION: FAILURE TO REPLICATE

Both additive and multiplicative combinations of importance and uncertainty have predicted information search in past research. In an attempt to obtain both relationships in a single experiment, this study manipulated importance in terms of incentive and difficulty, and it varied uncertainty in terms of ambiguity and incompatibility. Data from 240 subjects indicated that ambiguity depressed confidence and heightened direct and social search, but other predicted effects were not obtained. The failure to replicate prior research was attributed to use of manipulations between- as opposed to within-subjects.