A computer program to synthesize American Sign Language

A program is described that allows experimenters to generate American Sign Language forms by computer. The computer synthesis of such signs could allow major advances in the experimental investigation of the perception of sign language, much as computer-generated speech has done for the study of speech perception.     

A computer program to generate and measure random forms

A computer program is described that generates random form stimuli by a method parallel to that described by Attneave & Arnoult (1956) for construction forms with both angles and arcs in their perimeters. The program also performs a physical analysis of the forms by computing the values of a large number of physical variables describing each form. Already existing forms also may be analyzed by the program. Thus, it has the capability to perform physical analyses of approximations to natural forms.     

A rhythm recognition computer program to advocate interactivist perception

This paper advocates the main ideas of the interactive model of representation of Mark Bickhard and the assimilation/accommodation framework of Jean Piaget, through a rhythm recognition demonstration program. Although completely unsupervised, the program progressively learns to recognize more and more complex rhythms struck on the user’s keyboard. It does so without any recording of the input flow, and without any pattern matching in the usual sense. On the contrary, internal processes are dynamically constructed to follow and anticipate the user’s actions. We show that these processes are representations of the rhythms in the interactivist sense, and that they emerge from non representational grounds, avoiding the symbol-grounding problem. They are not copies or transductions of reality, but ideal internal constructions of the agent, avoiding the circularity pointed out by Piaget. In practice, the active nature of this recognition process allows it to work even with noisy and complex input flows.     

A Matlab function to estimate choice model parameters from paired-comparison data

Tversky (1972) has proposed a family of models for paired-comparison data that generalize the Bradley—Terry—Luce (BTL) model and can, therefore, apply to a diversity of situations in which the BTL model is doomed to fail. In this article, we present a Matlab function that makes it easy to specify any of these general models (EBA, Pretree, or BTL) and to estimate their parameters. The program eliminates the time-consuming task of constructing the likelihood function by hand for every single model. The usage of the program is illustratedby several examples. Features of the algorithm are outlined. The purpose of this article is to facilitate the use of probabilistic choice models in the analysis of data resulting from paired comparisons.     

How to check a computer program

The usual ways of checking computer programs have important flaws. A better way to check a program you have written is to have someone else write a program that does the same thing and then compare the output of the two programs over a wide range of input. Two examples are described.     

A ToolBook computer program to develop course objectives and assessment measures

College courses are generally developed because of current fashion in the field and/or student and faculty interest in some topic without reference to departmental or programmatic goals. Current calls and needs for accountability in higher education demand a more organized approach. A computer program, ToolBook 1.53, which provides information to the instructor about systematic development of courses and assessment of student outcomes, is described. The program supports the construction of outcome-oriented learning objectives and corresponding assessment techniques. Instructors who used this program to learn about how to construct such objectives showed an increase in knowledge and evaluated the program positively. Using the information provided in this program leads to an integrated approach to course design and development in which course objectives are linked to the college mission statement through departmental or program objectives.     

TETCORR: A computer program to compute smoothed tetrachoric correlation matrices

Although many programs exist for computing tetrachoric correlations, these programs typically lack one or more of the following features: (1) efficient processing of a large number of variables and computing of a matrix of coefficients; (2) a matrix-smoothing capability; (3) an accurate, reliable computing algorithm; (4) the ability to handle missing data; and (5) nominal cost. TETCORR, which combines an algorithm developed by Brown (1977) with starting values obtained from Divgi (1979a) for more efficient computation, was created to address these and other user concerns.     

FACTOR: A computer program to fit the exploratory factor analysis model

Exploratory factor analysis (EFA) is one of the most widely used statistical procedures in psychological research. It is a classic technique, but statistical research into EFA is still quite active, and various new developments and methods have been presented in recent years. The authors of the most popular statistical packages, however, do not seem very interested in incorporating these new advances. We present the program FACTOR, which was designed as a general, user-friendly program for computing EFA. It implements traditional procedures and indices and incorporates the benefits of some more recent developments. Two of the traditional procedures implemented are polychoric correlations and parallel analysis, the latter of which is considered to be one of the best methods for determining the number of factors or components to be retained. Good examples of the most recent developments implemented in our program are (1) minimum rank factor analysis, which is the only factor method that allows one to compute the proportion of variance explained by each factor, and (2) the simplimax rotation method, which has proved to be the most powerful rotation method available. Of these methods, only polychoric correlations are available in some commercial programs. A copy of the software, a demo, and a short manual can be obtained free of charge from the first author.