A low-cost universal feeder

Construction of a universal feeder for a cost of less than $200 is described. The feeder consists of two plywood panels, the first of which is circular and has grooves cut around its margin to hold reinforcers. This circular panel is secured to the second, rectangular panel so that it is free to rotate. A brush fixed onto the axle of a stepper motor above the circular panel sweeps the reinforcers away from the circular panel. Another stepper motor rotates the circular panel after each delivery to prepare the next reinforcer for delivery.     

Non-zero probabilities for universal generalizations

This article discusses the classical problem of zero probability of universal generalizations in Rudolf Carnap’s inductive logic. A correction rule for updating the inductive method on the basis of evidence will be presented. It will be shown that this rule has the effect that infinite streams of uniform evidence assume a non-zero limit probability. Since Carnap’s inductive logic is based on finite domains of individuals, the probability of the corresponding universal quantification changes accordingly. This implies that universal generalizations can receive positive prior and posterior probabilities, even for (countably) infinite domains.     

Selection for universal facial emotion

Facial expression is heralded as a communication system common to all human populations, and thus is generally accepted as a biologically based, universal behavior. Happiness, sadness, fear, anger, surprise, and disgust are universally recognized and produced emotions, and communication of these states is deemed essential in order to navigate the social environment. It is puzzling, however, how individuals are capable of producing similar facial expressions when facial musculature is known to vary greatly among individuals. Here, the authors show that although some facial muscles are not present in all individuals, and often exhibit great asymmetry (larger or absent on one side), the facial muscles that are essential in order to produce the universal facial expressions exhibited 100% occurrence and showed minimal gross asymmetry in 18 cadavers. This explains how universal facial expression production is achieved, implies that facial muscles have been selected for essential nonverbal communicative function, and yet also accommodate individual variation.     

A prelinguistic gestural universal of human communication

Several cognitive accounts of human communication argue for a language-independent, prelinguistic basis of human communication and language. The current study provides evidence for the universality of a prelinguistic gestural basis for human communication. We used a standardized, semi-natural elicitation procedure in seven very different cultures around the world to test for the existence of preverbal pointing in infants and their caregivers. Results were that by 10-14 months of age, infants and their caregivers pointed in all cultures in the same basic situation with similar frequencies and the same proto-typical morphology of the extended index finger. Infants' pointing was best predicted by age and caregiver pointing, but not by cultural group. Further analyses revealed a strong relation between the temporal unfolding of caregivers' and infants' pointing events, uncovering a structure of early prelinguistic gestural conversation. Findings support the existence of a gestural, language-independent universal of human communication that forms a culturally shared, prelinguistic basis for diversified linguistic communication.     

Considerations for evaluating universal screening assessments

Universal screening is a critical prerequisite to providing early school-based prevention and intervention services for students at risk for or with academic, behavioral, or emotional difficulties. Although use of academic and behavioral screening has become more prevalent, criteria for making informed decisions about appropriate screening tools are not readily available to those who work in educational settings. The purpose of this article is to (a) highlight several considerations about the appropriateness, technical adequacy, and usability of academic or behavioral screeners and (b) provide a general assessment of the current state of science pertaining to universal screening. The article concludes with considerations for policy and practice. The framework presented may be useful in guiding those interested in evaluating, selecting, and researching school-based universal screening assessments.     

A digitally controlled universal second-order filter block for biosignals with CMOS D/A converters

A universal second-order low-pass filter block with a digitally adjustable cutoff frequency is described. The filter section replaces conventional manually adjustable low-pass filters and is suitable for a wide range of biosignals such as EEG, EMG, and the recording of evoked potentials (ERPs). The advantages of digital control of filter parameters are briefly outlined and construction hints are given for a number of applications. The universal state-variable filter section may be programmed by any laboratory computer and does not require a complex installation procedure.     

Restricted thresholds for interval orders: A case of nonaxiomatizability by a universal sentence

Let $\text{P}$_n be the class of all finite interval orders that can be interval-represented using no more than n interval lengths or threshold levels. Thus $\text{P}$₁ is the class of finite semiorders, and $\text{P}$, the union of the $\text{P}$_n, is the class of finite interval orders. While each of $\text{P}$₁ and $\text{P}$ is axiomatizable by a universal sentence in first-order logic, no $\text{P}$_n for $\text{n ≧ 2}$ is axiomatizable in the same sense.     

A proposed universal model of problem solving for design,science and cognate fields

A modestly generic, innovative, problem solving process with roots in the study of design and scientific research problem solving is presented and motivated. It is argued to be the shared core process of all problem solving. At its heart is a recognition of five foci or nodes of change vital to the process (changes in problem and solution formulation, method, constraints, and partial solution proposals) together with a bootstrap marked by the formation of higher order knowledge about problem solving in the domain in tandem with the solving of specific problems, the essential feature of all learned improvement. None of these elements is entirely original, but the way they are made explicit and developed (rather than folded into fewer, more abstract, boxes) is argued to provide fresh understanding of the organisation and power of the process to deal with complex practical problems.     

Confirming universal generalizations

The purpose of this paper is to make a simple observation regarding the Johnson-Carnap continuum of inductive methods (see Johnson 1932, carnap 1952). From the outset, a common criticism of this continuum was its failure to permit the confirmation of universal generalizations: that is, if an event has unfailingly occurred in the past, the failure of the continuum to give some weight to the possibility that the event will continue to occur without fail in the future. The Johnson-Carnap continuum is the mathematical consequence of an axiom termed Johnson's sufficientness postulate, the thesis of this paper is that, properly viewed, the failure of the Johnson-Carnap continuum to confirm universal generalizations is not a deep fact, but rather an immediate consequence of the sufficientness postulate; and that if this postulate is modified in the minimal manner necessary to eliminate such an entailment, then the result is a new continuum that differs from the old one in precisely one respect: it enjoys the desideratum of confirming universal generalizations.