Structuring argumentation in a social constructivist framework: A pedagogy with computer support

What we usually think of as higher order skills in argumentation can be profitably viewed as systematic structures for organizing and representing information. Standard terms like line of argument, synthesis, analysis and draft can be viewed as ways of constructing, storing, and accessing data in a social context — data structures for social communication. What makes argument difficult are the multiple structures that arguers have to construct and negotiate when reading and composing. In this paper, we describe the WARRANT project, a project designed to identify data structures of written argument and to design and implement computer tools to aid in the reading and design of argument.     

Voice reaction times with recognition for Commodore computers

Hardware and software modifications are presented that allow for collection and recognition by a Commodore computer of spoken responses. Responses are timed with millisecond accuracy and automatically analyzed and scored. Accuracy data for this device from several experiments are presented. Potential applications and suggestions for improving recognition accuracy are also discussed.     

Monocular without stereopsis with and head movement

Random dots moving with various velocity gradients were presented to observers; the motion was yoked to head movement in one condition and to no head movement in another. In Experiment 1, 12 observers were shown motion gradients with sine, triangle, sawtooth, and square waveforms with amplitudes (equivalent disparities) of 12′ and 1° 53′. In Experiment 2, 48 observers were shown only the sinewave or square-wave gradient of 1° 53′ disparity either with or without head movement so that the observers’ expectation to see depth in one condition did not transfer to another. The main findings were: (1) with 12′ disparity, the head-movement condition produced perceived depth but almost no perceived motion, whereas the no-head-movement condition produced both perceived depth and perceived motion; (2) with 1° 53′ disparity, both conditions produced perceived depth and perceived motion; and (3) when the expectation to see depth was removed, the no-head-movement condition with the square-wave gradient produced no perceived depth, only motion. We suggest that monocular stereopsis with head movement can be achieved without perception of motion but monocular stereopsis without head movement requires perception of motion.     

Graphic precision: Controlling stimulus displays on IBM PC-compatible computers

Tachistoscopic presentation of stimuli on IBM PC-compatible computers is limited by a number of factors, including video retrace rates, screen scrolling, and the shape and density of picture elements. A method is presented for overcoming these difficulties through the use of enhanced graphic adapters or video graphic arrays. A C-language program demonstrates (1) synchronous scroll-free displays achieved by writing alternating images to “hidden” pages of video memory, (2) alternative techniques for erasing images, and (3) use of an empirically derived aspect ratio to produce symmetrical figures.     

THE WILL ROGERS ILLUSION IN JUDGMENTS ABOUT SOCIAL GROUPS

Abstract— Subjects' judgments of the mean of 12 scores were influenced by the way in which the scores were dichotomized. The estimated mean was higher when the three highest scores formed one group (e.g., payments for women) and the nine lowest formed the other (e.g., payments for men) than when the nine highest were one group and the three lowest the other. We call this phenomenon the Will Rogers Illusion (WRI). The WRI occurred only when estimates of the subgroup means were made prior to the estimates of the mean of the whole group. When the latter mean was judged first, the WRI was reversed. These and other data indicate that the means of subgroups can influence judgments of group means, a finding that is relevant to research on social stereotypes.