Applications of a computer algebra system in introductory statistics

Maple, a computer algebra system, is employed in introductory statistics courses to promote conceptual learning by students of statistical principles without direct use of mathematics. Maple’s symbolic computation, graphic display, and animation capabilities support an integrated set of procedures for active study of sampling distributions and concepts related to samples, populations, and statistical decision making, error, and power. Students select parameter values for one-line commands and examine the effects of alternatives on computer-generated graphical representations of distributions. The 20 procedures written to support active student exploration of basic statistical concepts are described, and examples of exercises to support their use are provided.     

Comparing the variances of dependent groups

Recently several new attempts have been made to find a robust method for comparing the variances ofJ dependent random variables. However, empirical studies have shown that all of these procedures can give unsatisfactory results. This paper examines several new procedures that are derived heuristically. One of these procedures was found to perform better than all of the robust procedures studied here, and so it is recommended for general use.The author would like to thank the reviewers for their very helpful comments on an earlier draft of this paper.     

Balanced incomplete blocks to control individual differences

Balanced incomplete block designs are used when there are reasons that preclude the use of repeated measurements designs, particularly when there are at least two factors, each with several levels. However, these designs are usually not used when interaction effects are of interest, because they involve the confounding of the interactions with subject or group differences. This paper describes special computational procedures that can be employed to obtain partial, but unconfounded, information about interaction effects.     

Increasing cerebrospinal fluid cell count with the sedimentation chamber using polycationic coated slides

The use of glass slides coated with the cationic polymer polydimethyldiallylammonium-chlorid for cell enrichment procedures results in an increasing number of cells on the slicks and changed quantitative results of cell differentiation. These investigations are important for quantitative analysis of cell populations.     

on the acoustic analysis of primate vocalizations

The acoustic theory of speech production relates articulatory maneuvers to acoustic attributes of speech. Some procedures are discussed that make use of this theory to analyze the vocalizations of nonhuman primates. These procedures make use of sound spectrograms, oscillograms, and computer-implemented analogs of the primate vocal apparatus as well as anatomical measurements. The use of these techniques in recent studies of nonhuman primate vocalizations is reviewed. These studies show that nonhuman primates lack the anatomical apparatus that is necessary for the production of the full range of human speech. Some unresolved questions concerning the structure of nonhuman primate utterances are discussed with regard to human linguistic ability.     

Rotation to achieve factorial invariance

Under certain conditions it is reasonable to assume that the same factor pattern matrix will describe the regression of observed on factor scores in different populations. However, ordinary factoring procedures will not reveal in general the existence of such a factor pattern matrix. Two procedures for rotating any number of factor pattern matrices based on different populations to conform to a single best fitting factor pattern matrix are developed in this paper. It is assumed that the same number of factors have been determined for each population. Both procedures will yield oblique results in the various populations. The procedures are illustrated with data taken from the 1939 Holzinger-Swineford monograph. Four groups of individuals are utilized.     

Was sagen „objektive“ Messverfahren über Sexualstraftäter?

A great deal of effort has been made to use so-called objective measurements in men convicted of child sexual abuse in recent years. The aim of using these procedures is to measure sexual preference for children more effectively while being less vulnerable for deception and to add information to subjective reports. In this paper it was investigated why research activities in this area have increased and what so-called “objective” measurements can reveal about sexual offenders. This article will discuss possible pros and cons of the use of such procedures for forensic court reports or in the context of therapy in a forensic setting.     

Say-do correspondence to improve disruptive behaviors in adults with Down's syndrome

The most acknowledged strategies for the treatment of disruptive behaviours are those that are based on direct contingency management. Other procedures allow the therapist, or educational agent, not to be present in the context in which the behavioural change has to take place: the say-do correspondence training procedures, which have proven effective across behaviours and populations. Nevertheless, there is surprisingly little evidence of the effectiveness of such procedures with populations presenting developmental disabilities. This study describes the implementation of say-do correspondence training to modify 5 disruptive behaviours present in 5 adult subjects diagnosed with Down's syndrome, showing very positive results. The advantages of using say-do correspondence training procedures in developmental disabilities are discussed.     

Creating noisy stimuli

A method for creating a variety of pseudo-random 'noisy' stimuli that possess several useful statistical and phenomenal features for psychophysical experimentation is outlined. These stimuli are derived from a pseudo-periodic function known as multidimensional noise. This class of function has the desirable property that it is periodic, defined on a fixed domain, is roughly symmetric, and is stochastic, yet consistent and repeatable. The stimuli that can be created from these functions have a controllable amount of complexity and self-similarity properties that are further useful when generating naturalistic looking objects and surfaces for investigation. The paper addresses the creation and manipulation of stimuli with the use of noise, including an overview of this particular implementation. Stimuli derived from these procedures have been used successfully in several shape and surface perception experiments and are presented here for use by others and further discussion as to their utility.     

Diagnose von Intelligenzminderung

The diagnostics of intellectual disability is a complex process which must be carried out on several levels using different methods (multidimensional diagnostics). The expertise of the test leader is at least just as important as the selection of suitable procedures. The responsible use of test procedures requires comprehensive knowledge of test diagnostics and sufficient experience in the examination of people in the appropriate age group with intellectual disabilities and a good familiarity with the procedures used. This article provides information on the epidemiology of intellectual disability, supplies definitions and classification of the grade of severity of intellectual disabilities and describes the diagnostic pathway.     

Percentage of nonoverlapping corrected data

In the present study, we proposed a modification in one of the most frequently applied effect-size procedures in single-case data analysis: the percentage of nonoverlapping data. In contrast with other techniques, the calculus and interpretation of this procedure are straightforward and can be easily complemented by visual inspection of the graphed data. Although the percentage of nonoverlapping data has been found to perform reasonably well in N = 1 data, the magnitude of effect estimates that it yields can be distorted by trend and autocorrelation. Therefore, the data-correction procedure focuses on removing the baseline trend from data prior to estimating the change produced in the behavior as a result of intervention. A simulation study was carried out in order to compare the original and the modified procedures in several experimental conditions. The results suggest that the new proposal is unaffected by trend and autocorrelation and that it can be used in case of unstable baselines and sequentially related measurements.     

SECOND-ORDER DEVELOPMENT IN INTERPERSONAL COMMUNICATION

Developmental studies in interpersonal communication have focused on first-order development—relational development within a given matrix of rules. Neglected has been the interpersonal communication that results in second-order development—the creation of a new interpersonal system. A rationale, a model, and procedures for the study of second-order development are presented. A case is analyzed, and several conclusions are proposed. Second-order development (1) follows a predictable pattern, (2) it is marked by personal struggle, (3) its outcomes are oblique to its happening, and (4) it involves risk. Future research is directed toward the effects on second-order development of certain kinds of episodes and their sequential order and toward the use of the procedures demonstrated in analyzing the development of long-standing relationships.     

Estimating Success in Predicting a Variable with Nominal Measurement Using Other Variables with Nominal Measurements

In this article we are concerned with the situation where one is estimating the outcome of a variable Y, with nominal measurement, on the basis of the outcomes of several predictor variables, X 1, X 2, ..., X r, each with nominal measurement. We assume that we have a random sample from the population. Here we are interested in estimating p, the probability of successfully predicting a new Y from the population, given the X measurements for this new observation. We begin by proposing an estimator, p_a, which is the success rate in predicting Y from the current sample. We show that this estimator is always biased upwards. We then propose a second estimator, p_b, which divides the original sample into two groups, a holdout group and a training group, in order to estimate p. We show that procedures such as these are always biased downwards, no matter how we divide the original sample into the two groups. Because one of these estimators tends to overestimate p while the other tends to underestimate p, we propose as a heuristic solution to use the mean of these two estimators, p_c, as an estimator for p. We then perform several simulation studies to compare the three estimators with respect to both bias and MSE. These simulations seem to confirm that $ p c is a better estimator than either of the other two.     

THE TOKEN ECONOMY: A DECADE LATER

In the last decade, the token economy has been extended widely across populations and behaviors in treatment, rehabilitation, educational, and community settings. Outcome research has expanded as well to include large-scale program evaluations and comparative and combined treatment studies of the token economy. In a previous review (Kazdin & Bootzin, 1972), several obstacles were identified for the effective application of the token economy. These included identifying procedures to enhance program efficacy, to train staff, to overcome client resistance, and to promote long-term maintenance and transfer of training. The present paper discusses recent advances in research and reviews progress on the major issues identified previously. New issues have become salient in the last decade that pertain to the extension of the token economy to institutional settings. The demands for maintaining the integrity of treatment, the ability to integrate token economies within existing institutional constraints, and the disseminability of the procedures on a large scale are major issues that may dictate the future of the token economy.     

Cognitive and behavioral self-control strategies: Applications for the clinical management of adult stutterers

A model of therapy for adult stutterers which emphasizes the role of cognition in mediating the conditions for behavioral change is described. The philosophy of the program along with the specific forms and effects of several self-control strategies are discussed in relation to: (1) expectancy formation and the attainment of goals; (2) speech modification procedures; (3) transference of clinical gains; and (4) assessment of results. The use of cognitive restructuring procedures, self-instructional strategies, imagery and other coping skills for the management of speech-related stress is outlined. The importance of developing self-management and self-monitoring programs that clients may use in ongoing confrontations with real-life problems is emphasized in defining responsible behavior and the responsibility for change.     

Genetic linkage in bipolar disorder

Bipolar disorder is an etiologically complex syndrome that is clearly heritable. Multiple genes, working singly or in concert, are likely to cause susceptibility to bipolar disorder. Bipolar disorder genetics has progressed rapidly in the last few decades. However, specific causal genetic mutations for bipolar disorder have not been identified. Both candidate gene studies and complete genome screens have been conducted. They have provided compelling evidence for several potential bipolar disorder susceptibility loci in several regions of the genome. The strongest evidence suggests that bipolar disorder susceptibility loci may lie in one or more genomic regions on chromosomes 18, 4, and 21. Other regions of interest, including those on chromosomes 5 and 8, are also under investigation. New approaches, such as the use of genetically isolated populations and the use of endophenotypes for bipolar disorder, hold promise for continued advancement in the search to identify specific bipolar disorder genes.     

Multiperspectival designs and processes in interpretative phenomenological analysis research

ABSTRACT

Researchers using interpretative phenomenological analysis (IPA) within applied research typically use homogenous samples exploring shared perspectives on a single phenomenon of interest. This article explores the challenges and opportunities involved with developing rigorous and epistemologically coherent research designs for capturing more complex and systemic experiential phenomena, through the use of multiple perspectives to explore the same phenomenon. We outline a series of multiple perspective designs and analytic procedures that can be adapted and used across many diverse settings and populations. Whilst building upon existing approaches within qualitative methods and IPA, these designs and procedures are intended to scaffold clear routes to practical application, psychological intervention, the design of behaviour change interventions, and other recommendations for policy and practice. We discuss a variety of conceptual antecedents which situate these designs within phenomenology, pluralistic idiography, qualitative psychology, and wider debates within psychology and other social and behavioural sciences.     

Ruler vs. the Apple II/FIRST system analysis of analog signals in classical conditioning

In our judgment, the Apple II/FIRST system (Scandrett & Gormezano, 1980) is an efficient and versatile system for experimental control and data acquisition in classical conditioning experiments. However, these attributes would be of limited value if the system did not extract measures from our analog signals with a high degree of correspondence with our ruler measurement procedures. Accordingly, we determined the system’s validity in extracting measures of CR occurrence and CR latency in three conditioning experiments. Pearson productmoment correlation coefficients indicated a very satisfactory degree of agreement on measurements made by the Apple II/FIRST system and ruler. Moreover, intraclass correlations and analysis of variance procedures applied to percent CRs and CR latency revealed several small, but divergent, differences between ruler and computer measurement of CR latency across the three experiments. However, subsequent analyses of variance revealed that the number and pattern of significant sources of variation for ruler or computer measurements were virtually identical. Accordingly, we have concluded that our system can successfully replace our traditional method of ruler measurement.     

Adaptive rating scales in sequential decisions

The benefits gained in decision research through the use of computer-controlled procedures, as opposed to the use of traditional pencil-and-paper techniques, can exceed the expected gains of efficiency and standardization. Computers extend the scope of a sequential decision making paradigm by enhancing (1) the strength of experimental design, (2) reliability of measurement, (3) procedural flexibility, and (4) single-subject data analysis. Data are reported that indicate the necessity of using computers to obtain reliable measurements and valid results for this type of decision research.