From the desk of the IFA president : International fluency association priorities: A poll of potential members

Potential members of the International Fluency Association (IFA) were polled regarding their fluency interests and perceived priorities for the organization during the year it was founded (in 1990). Results from 201 respondents indicated that a need for the IFA existed among researchers, clinicians, and representatives of self-help organizations for people who stutter. Improving the quality of treatment for those who stutter was considered the highest priority by all three groups. Researchers were of the opinion that the Journal of Fluency Disorders should be of higher quality than it had been in the past, and clinicians were most interested in reviews of new and relevant materials.     

Analysis of the components of disparity in Wilde's dot-row phenomenon

Summary In this study on Wilde's phenomenon (Wilde 1950) the two components of disparity, one of them processing displacement, and the other one apparent rotation, are analysed in terms of dependence on the disparity of the end-lines of the pattern (), and on the percentage of magnification (M) of one of the monocular patterns in relation to the other one. It was found that the component of disparity for displacement ' can be expressed as a linear regression equation '=–a+b.The component of disparity for rotation, expressed as a percentage of magnification effective for rotation (M) can be expressed as M=a–b₁+b₂M.It was concluded that the two components of disparity are processed through independent parallel channels, the processing of the component of disparity for displacement being the faster process, accounting for the larger part of the total disparity.     

Maximum likelihood estimation for Luce's choice model

A terminology for general choice models based on the choice axiom is given. It applies to all kinds of choice experiments, such as confusion choice experiments, paired comparisons, triadic comparisons, directional rankings, scores on binary test items, and others. Maximum likelihood estimation for such general choice models is considered. Conditions for the uniqueness of maximum likelihood estimates are given, and it is shown that the estimates can be derived by iterative proportional fitting. This offers the opportunity of a general test of the choice axiom for all kinds of choice experiments using the likelihood ratio. The estimation and testing procedure is applied to data from a form recognition experiment, reported by W. A. Wagenaar (Nederlands Tijdschrift voor de Psychologie, 1968, 23, 96–108).     

Indirect social influence: Change in judgmental process or anticipatory conformity?

In three experiments, subjects imposed sentence in a criminal case before and after reading the harsh sentence imposed by the trial judge. They then read and imposed sentence in another case. In one experimental condition the subjects anticipated learning the judge's sentence in Case 2; in the other condition they were told not to anticipate learning the judge's sentence. Control subjects made their judgments without ever seeing the judge's sentence. Direct influence was the change in sentences within cases; indirect influence was the difference between initial sentences in Cases 1 and 2. Though direct influence was minimal and not significant, indirect influence was substantial, and was greater in the anticipation than no-anticipation than control conditions, indicating that both modification of the judgmental process and anticipatory conformity were operating. Indirect influence may then reflect a change of either type, depending on a number of methodological and other factors.     

Storage mode of geometrical dimensions in a two-stimulus matching paradigm

In a two-stimulus matching paradigm requiring “same” and “different” responses to simple geometric dimensions, the successive stimulus presentation mode with several retention intervals was compared to a simultaneous stimulus presentation mode. For the simultaneous condition, the data suggested a wholistic template matching process, but in none of the successive conditions was template matching indicated. The retention interval of the successive condition allows the subject to analyze out the target dimension from the first two-dimensional stimulus. The ability to anticipate the value of the target dimension in the second stimulus could also influence the representation of the first stimulus. The findings shed some light upon the perceptual interactions between dimensions that constitute the stimulus. In particular, an outside-to-inside order of iconic scanning appeared to be supported by the data.     

Hardware and software evolution of an adaptive ability measurement system

A software system for the administration of six different strategies of adaptive ability tests in a variety of formats was developed both on a large-scale time-sharing system and on a real-time minicomputer system. Factors influencing both hardware selection and software design are discussed.