Behavior Research Methods Research Articles

New methods in ambulatory blood pressure monitoring: Interactive monitoring and detection of posture and movement patterns

Psychophysiological monitoring can be used to assess emotional reactivity in cardiovascular measures. Since blood pressure (BP) variability in daily life is primarily caused by physical activity, metabolic and nonmetabolic effects are confounded. A newly developed method of multiple accelerometry allows for the control of such unwanted variances by continuously detecting posture, general activity, and distinct movement patterns. Contingent on episodes of additional heart rate (AHR), an indicator of emotional reactivity, BP measurements can be triggered and participants prompted to enter their current mood in a handheld PC. To evaluate both new methods for BP research, we performed 24-h ambulatory monitoring with 40 normotensive student participants, an evaluation designed to include standard settings for a controlled comparison (library vs. cinema). Findings indicated that the group at the cinema showed higher values of AHR, but group differences in BP were not observed. On the whole, such multiple accelerometry and interactive monitoring appear to be useful methods in behavior research.

Improving psychometric methods in health education and health behavior research

The articles in this supplement to Health Education Research grew out of discussions among the coeditors as to the best way to further promote the use of advanced psychometric methods in health education and health behavior research. Item response modeling (IRM), also referred to as item response theory, is well established and widely implemented in educational measurement, but its application is lagging in our area. A number of issues seem to stunt the application of IRM methods: (i) few IRM applications have been presented in the context of health education and health behavior research; (ii) lack of awareness as to what IRM can do beyond assessing the psychometric properties of a scale; (iii) lack of psychometricians trained in our field; (iv) current software is not user friendly and (v) few training opportunities are available to researchers in our area. In an attempt to address some of these issues, the National Cancer Institute (NCI) in collaboration with the coeditors of this supplement devised strategies to promote the development of better scales through improved methods. Al

High-dimensional semantic space accounts of priming

A broad range of priming data has been used to explore the structure of semantic memory and to test between models of word representation. In this paper, we examine the computational mechanisms required to learn distributed semantic representations for words directly from unsupervised experience with language. To best account for the variety of priming data, we introduce a holographic model of the lexicon that learns word meaning and order information from experience with a large text corpus. Both context and order information are learned into the same composite representation by simple summation and convolution mechanisms (cf. Murdock, B.B. (1982). A theory for the storage and retrieval of item and associative information. Psychological Review, 89, 609–626). We compare the similarity structure of representations learned by the holographic model, Latent Semantic Analysis (LSA; Landauer, T.K., & Dumais, S.T. (1997). A solution to Plato’s problem: The latent semantic analysis theory of acquisition, induction and representation of knowledge. Psychological Review, 104, 211–240), and the Hyperspace Analogue to Language (HAL; Lund, K., & Burgess, C., (1996). Producing high-dimensional semantic spaces from lexical co-occurrence. Behavior Research Methods, Instrumentation, and Computers, 28, 203–208) at predicting human data in a variety of semantic, associated, and mediated priming experiments. We found that both word context and word order information are necessary to account for trends in the human data. The representations learned from the holographic system incorporate both types of structure, and are shown to account for priming phenomena across several tasks.

Comparison of the ASA, MOBS, and ZEST threshold methods

The modified binary search, or MOBS, technique is an adaptive, non-parametric procedure for estimating thresholds [Tyrrell, R. A, & Owens, D. A. (1988). A rapid technique to assess the resting states of eyes and other threshold phenomena: the modified binary search (MOBS). Behavior Research Methods, Instruments, and Computers, 20, 137–141.], which has recently been incorporated into a commercially available perimeter. Information regarding the performance of this technique is limited, however. We performed Monte Carlos simulations on the MOBS procedure, as well as on a Zippy Estimation by Sequential Testing, or ZEST, procedure ( King-Smith, Grigsby, Vingrys, Benes, & Supowit, 1994) and an Accelerated Stochastic Approximation, or ASA, procedure ( Kesten, 1958) for comparison. The efficiency, convergence probability, and robustness to false positive and false negative responses were determined. Differences between the three procedures typically were small, the most prominent being the number of presentations required to estimate threshold.

THINK PIECE:Mixed Methods as Methodological Innovations: Problems and Prospects

One of the most recent methodological innovations has been in the area of what is now referred to as Mixed Methodology (hereafter MM). The most serious and comprehensive volume in this area is probably, The Handbook of Mixed Methods in Social and Behavioral Research (Tashakkori & Teddlie, 2003). The Handbook is a sophisticated compilation of various authors who explore the many dimensions of this emerging field. It is not my intention to review the volume, but rather to make the claim that MM still has a host of methodological issues that must be clarified before the potential development of this area can take their place as being relevant to the social and behavioural sciences. What I would like to do, then, is offer some ideas which can become the basis of further debate. The intent is to present an overview and summary of what I consider to be the major problems that still exist in the area of MM.

Separating out the levels: Globalization, identity, and the Ekistic Grid in sociological perspective

The author is S.D. Clark Professor of Sociology, Emeritus, at the University of Toronto. His special areas are Urban Sociology and Social Ecology, with a focus on built environments. His most recent book is Time Use: Expanding Explanation in the Social Sciences (Boulder, CO,Paradigm Publishers, 2005). Previous books include: Man and his Urban Environment: A Sociological Approach (1970 and 1976), Environmental Choice, Human Behavior, and Residential Satisfaction (1977), From Sun to Sun: Daily Obligations and Community Structure in the Lives of Employed Women and their Families (1985), Methods in Environmental and Behavioral Research (1987), and the Handbook of Environmental Sociology (2002). He is a member of the World Society for Ekistics, as well as the Royal Society of Canada. The text that follows is a slightly revised and edited version of a paper presented at the international symposion on Globalization and Local Identity, organized jointly by the World Society for Ekistics and the University of Shiga Prefecture in Hikone, Japan, 19-24 September, 2005.

Face processing in humans is compatible with a simple shape–based model of vision

Understanding how the human visual system recognizes objects is one of the key challenges in neuroscience. Inspired by a large body of physiological evidence, a general class of recognition models has emerged, which is based on a hierarchical organization of visual processing, with succeeding stages being sensitive to image features of increasing complexity. However, these models appear to be incompatible with some well-known psychophysical results. Prominent among these are experiments investigating recognition impairments caused by vertical inversion of images, especially those of faces. It has been reported that faces that differ 'featurally' are much easier to distinguish when inverted than those that differ 'configurally'; a finding that is difficult to reconcile with the physiological models. Here, we show that after controlling for subjects' expectations, there is no difference between 'featurally' and 'configurally' transformed faces in terms of inversion effect. This result reinforces the plausibility of simple hierarchical models of object representation and recognition in the cortex.

Paradigm Shift in Social Science Research: A Significance Testing and Effect Size Estimation Rapprochement?Paradigm Shift in Social Science Research: A Significance Testing and Effect Size Estimation Rapprochement?

During the past 40 years, the vast majority of students trained in the social sciences have been taught the of null- hypothesis significance-testing (NHST). Social science researchers following the received review have approached their work with a heavy reliance on statistical tests, which have been strongly identified with probability or testing. The process of rejecting or retaining the null hypothesis has dictated this research, leaving the hope of accepting an alternative, explanatory hypothesis to the mercies of somewhat arbitrary designations of chance probabilities (e.g., p <.05). However, over the years a growing number of researchers have argued against the received view of statistical inference (e.g., Carver, 1978; Cohen, 1994; Hunter, 1997; Loftus, 1996). In fact, the American Psychological Association's (APA) Board of Scientific Affairs has recently considered prohibiting the reporting of significance tests in APA journals (Shrout, 1997). However, there are strong supporters of NHST, who state that critiques of NHST tend to be metatheoretical assertions that do not take into account the fact that rejection of H0 is only one factor in the practice of testing a theoretical hypothesis (Abelson, 1997; Chow, 1996; Cortina, & Dunlap, 1997; Frick, 1996). Rex B. Kline, in his recent book Beyond Significance Testing: Reforming Data Analysis Methods in Behavioral Research, takes issue with the received view and foresees a future in which the NHST in social science research will diminish. Kline is calling for a paradigm shift, in which social science will more closely reflect the hard sciences. Kline concisely explicates his vision: Most studies in the future will not use statistical tests as the primary decision criterion, and those that do will concern only very specific problems for which variations of NHST may be appropriate, such as equivalence testing or inferential confidence intervals. It is also envisioned that the social sciences will become more like the natural sciences. That is, one will report the directions and magnitudes of one's effects; determine whether they

PREPARING TOMORROW'S BEHAVIOR‐ANALYTIC RESEARCHERS: A REVIEW OF RESEARCH METHODS IN APPLIED BEHAVIOR ANALYSIS BY JON BAILEY AND MARY BURCH

Although there are many books about behavioral research methods, there are very few guidebooks. This review describes a book by Jon S. Bailey and Mary R. Burch that has been written specifically as a guide for the new researcher. Replete with helpful tips on navigating the research process, the book is organized into 10 sequential research steps that guide the reader through each phase of conceptualizing, conducting, and analyzing an applied study. Although not as detailed as other texts with regard to the specifics of methodology, this book is reader‐friendly and accessible to both undergraduates and graduate students who are beginning the process of becoming applied behavior‐analytic researchers.

Beyond Significance Testing: Reforming Data Analysis Methods in Behavioral Research.

REX B. KLINE Beyond Significance Testing: Reforming Data Analysis Methods in Behavioral Research Washington, DC: American Psychological Association, 2004, 336 pages (ISBN 1-59147-118-4, US$49.95 Hardcover) In 1999, a blue-ribbon task force assembled by the American Psychological Association published their findings with regards to the long-standing controversy pertaining to null hypothesis testing (NHST). The task force dictated effect sizes and confidence intervals be reported, and p values and dichotomous accept-reject decisions be given less weight. Editorial policies in a number of journals came to reflect the views of the task force as did a subsequent revision to the American Psychological Association Publication Manual. Rex B. Kline wrote Beyond Significance Testing. Reforming Data Analysis Methods in Behavioral Research as a follow-up to both the task force recommendations and the revision to the publication manual. Kline's 1998 book Principles and Practice of Structural Equation Modeling (Guilford Press) was well received and a second edition is being published this fall. In Beyond Significance Testing, Kline reviews the controversy regarding testing, offers methods for effect size and confidence interval estimation, and suggests some methodologies. There is an accompanying website that includes resources for instructors and students. Part I of the book is a review of fundamental concepts and the debate regarding testing. Part II provides statistics for effect size and confidence interval estimation for parametric and nonparametric two-group, oneway, and factorial designs. Part III examines metaanalysis, resampling, and Bayesian estimation procedures. In the first chapter, Kline provides a scholarly summary of the null hypothesis testing debate concluding with the APA task force findings and what Kline regards as ambiguous recommendations in the publication manual. Kline predicts the future will see a smaller role for traditional statistical testing (p values) in psychology. This change will take time and may not occur until the next generation of researchers are trained, but Kline anticipates the social sciences will then become more like the natural sciences in that we will report the directions and magnitudes of our effects, determine whether they replicate, and evaluate them for their theoretical, clinical, or practical significance (p. 15). Chapter 2 is a review of fundamental concepts of research design, including sampling and estimation, the logic of statistical testing, and t, F, and chi-square tests. The problems with statistical tests are revisited in Chapter 3. What follows is a long list of errors in interpretation of p values and conclusions made after null hypothesis testing. The emphasis on null hypothesis testing in psychology is also argued to inhibit advancement of the discipline. To be fair, Kline recognizes there is yet no magical alternative to statistical tests and that such tests are appropriate in some circumstances when applied correctly. Nonetheless, Kline envisions a future where effect sizes and confidence intervals are reported, substantive rather than statistical predominates, and NHST-Centric thinking has diminished. Part II covers effect size and confidence interval calculations. Chapter 4 is a presentation of parametric effect size indexes. Independent and dependent sample statistics are covered separately. The textbook's website has a supplementary chapter on twogroup multivariate designs. Group difference indexes such as d are distinguished from measures of association such as r. Case level analyses of group differences are also reviewed. Sections not relevant to a reader's needs can be skipped without loss of continuity. Interpretive guidelines for effect size magnitude and how one might be fooled by effect size estimation are sections that should not be passed over. …

Time Window from Visual Images to Visual Short-Term Memory: Consolidation or Integration?

Time Window from Visual Images to Visual Short-Term Memory: Consolidation or Integration?

Book Review: Handbook of Mixed Methods in Social &amp; Behavioral Research

Book Review: Handbook of Mixed Methods in Social &amp; Behavioral Research

Utilizing a Computerized Video Poker Simulation for the Collection of Data on Gambling Behavior

The current paper presents data collected utilizing a computerized video poker simulation that was published in Behavior Research Methods, Instruments, and Computers by Dixon, MacLin, and Hayes (1999). To date no published studies have demonstrated the utility of the simulation or presented the possible data that may emerge from using the program. Eleven undergraduates played the simulation for 100 trials each for course extra-credit and the opportunity to win additional monetary compensation. Results suggest that there are regularities within and across participants on both temporal and subjective dependent variables during their play of the video poker game. These variables included response latencies, decision-making times, and subjective probability estimations. Implications of these data for the successful treatment of pathological gamblers and suggestions for further behavioral research on gambling are discussed.

What Does the Implicit Association Test Measure? A Test of the Convergent and Discriminant Validity of Prejudice-Related IATs

What Does the Implicit Association Test Measure? A Test of the Convergent and Discriminant Validity of Prejudice-Related IATs

University of North Texas: Master of science in behavior analysis.

In 1989, the University of North Texas was authorized by the Texas Coordinating Board of Higher Education to offer a master of science degree in behavior analysis. In 1990, the degree program appeared for the first time in the UNT Graduate Catalog. Due to the wide variety of career applications within behavior analysis, the program was designed to produce behavior analysts who could rise to whatever circumstance, opportunity, or challenge they faced--specifically, to perform at a high professional level in any of a variety of employment settings and/or to enter into doctoral programs with a thorough background in behavior analysis. In the paragraphs below, we briefly describe the curriculum, the enrollment history, the faculty, student involvement, and the current status of the program in the context of the department. Perhaps of greatest importance to most readers is what do UNT graduates do after receiving their master's degrees? Because our graduates can best answer that question, we asked a few of them, who represent the broad spectrum of activities and positions that characterize UNT graduates. Their answers are in the text boxes in the margins of this paper. Behavior analysis covers a large body of knowledge and a broad range of activities. The UNT program is fortunate in having an entire curriculum devoted to behavior analysis, as well as a faculty willing to accomplish the program's goal of preparing its students for interesting, remunerative, and fulfilling lifelong careers in behavior analysis. Toward that end, the program includes in-depth coursework in the principles, methods, techniques, theory, and philosophy of behavior analysis and it provides supervised experience in several areas of application and research. Students choose one of two concentrations: the applied concentration is for students who plan to seek employment upon obtaining the Master's Degree and the General/Research concentration is for students who plan to pursue a doctorate upon completion of the master's degree. The concentrations share 7 core courses that cover behavioral principles, surveys of experimental analysis and applied behavior analysis literatures, research methods, theory and philosophy, and quantitative methods. Students in the applied concentration go on to take three required courses in applications and have several additional applied electives to choose from, including a 2-course sequence in OBM and a 3course sequence in autism. General/research students take one required course beyond the core, one or two semesters of research problems, and one or two electives. Electives in both concentrations may be behavior analysis courses or courses in other departments. Computer science, business administration, psychology and biology courses, as well as seminar courses in behavior analysis have been chosen as electives. Applied students have a total of 3 faculty- supervised practica in at least two different applied fields and an internship that is faculty-approved and supervised by behavior analysts in the field. All students complete a data -based thesis, usually experimental in nature. The course requirements and course descriptions may be found on the department web page at www.scs.unt.edu/depts/behv UNT's master's degree program was the first graduate program to be accredited by the Association for Behavior Analysis (1993) and the first to be re-accredited (1998). Four of its faculty members are board certified behavior analysts (BCBA). Graduates of the master's program applied concentration will have met the eligibility requirements published by the Behavior Analysis Certification Board for taking the national examination. Enrollment History Prior to approval of the master's degree program, four graduate courses in behavior analysis had been offered each year between 1984 and 1989. Several students were enrolled during that period in an interdisciplinary master's degree program offered by the Graduate School. …

Estimation for Polynomial Structural Equation Models

Structural equation analysis is one of the most widely used statistical methods in social and behavioral science research and has become a popular tool in marketing. Subject matter needs for considering nonlinear structural models have been well documented. But current fitting procedures are available only for a limited class of models. In this article a systematic statistical approach is developed for the general polynomial structural equation model. The new procedure applies a method of moments procedure similar to the one used in errors-in-variables regression to the factor score estimates from the measurement model fit. The asymptotic properties of the estimator are derived, and a modified estimator with better small-sample properties is introduced. Simulation studies are reported to show the usefulness of the procedure and to compare its performance to other methods. An example from a substance abuse prevention study is also discussed.

The virtues of language: History in language, linguistics and texts Ed. by Dieter Stein and Rosanna Sornicola (review)

478 LANGUAGE, VOLUME 76, NUMBER 2 (2000) Second language acquisition and the critical period hypothesis. Ed. by David Birdsong. (Second language acquisition research: Theoretical and methodological issues 3.) Mahwah, NJ: Lawrence Erlbaum, 1999. Pp. x, 191. The third in a series on theoretical and methodological issues in second language acquisition (SLA) research, this volume was inspired by the 1996 Association Internationale de Linguistique Appliquée symposium, 'New perspectives on the critical period for SLA'. The editor notes in his introductory chapter (1-18) that several versions of the critical period hypothesis (CPH) are represented in the book, allowing a broad perspective on the issue. In the six chapters that follow, international contributors to the volume are evenly divided in the discussion for and against critical periods in SLA. Diversifying the volume are the range of disciplines that take up the issue and the variety of evidence put forth, including but not limited to morphological, syntactic, and phonological data. The three chapters following the introduction present data from SLA studies that support the CPH. Starting from a neurophysiological approach, Christine M. Weber-Fox and Helen T. Neville (23-36) present the hypothesis that cerebral subsystems for semantics and grammar are differentially affected by critical periods (CPs). The authors' incorporation of both behavioral and electrophysiological research methods provides compelling evidence for this hypothesis . Tames R. Hurford and Simon Kirby (39-62) describe simulations that suggest that evolutionary processes contribute to a CP and discuss the implications for SLA briefly. Lynn Eubank and Kevin R. Gregg (65-93) bring a thorough linguistic theory analysis of the CPH to the volume. Asserting that CPHs in adult SLA demand refinement, the authors demonstrate ways that this refinement can come from linguistic theory. Also discussed in this chapter are fundamental distinctions of critical and/or sensitive periods and the role of physiological evidence for CPs in SLA. Three remaining chapters provide counter explanations that also fit the facts of SLA. James E. Flege (101-27) examines the discontinuity predicted by CPH vs. linear function in second language pronunciation and age of arrival. One view offered is that second language phonological production is limited by accuracy in first language perception. Theo Bongaerts (133-55) reports on three studies that he and his colleagues performed which attempted to address the concern that ultimate attainment studies focus on advanced learners. This chapter suggests that motivation , access, and training in perception and production may contribute to high levels of phonological attainment. The identification of native-like late learners of English and French from Dutch-speaking backgrounds supports this suggestion. In the final chapter (161-78), Ellen Bialystok and Kenji Hakuta challenge the assumption of causality between age and level of attainment. They explore results that fail to support the CPH in both the linguistic and cognitive evidence, concluding that there is reason to accept a null hypothesis contradicting the CPH. The 'younger equals better' hypothesis for SLA remains under advisement. In this regard the virtue of the contributions presented here is that they offer a broad scope for future research. Researchers, graduate students, and teachers will find this volume a useful equilibration of the issues. [Daniel O. Jackson , University of Pennsylvania.] The virtues of language: History in language , linguistics and texts. Ed. by Dieter Stein and Rosanna Sornicola. Amsterdam: John Benjamins, 1998. Pp. viii, 232. This collection of thirteen essays is dedicated to the memory of Thomas Frank (1925-1990), who held the Chair ofthe History ofEnglish at the University of Naples from 1982 until his death. The first essay, E. F. Konrad Koerner's revised obituary article (originally published in Historiographia Ling üistica 17.421-26 [1990]), summarizes the honorée's many accomplishments over a long and distinguished career (3-10). It contains his bibliography from 1953-1996, which includes a number of studies in the history of linguistics such as a monograph on Bishop Tohn Wilkins's (1714-1792) Essay towards a real character and a philosophical language of 1668 (Guida: Naples, 1979). Rosanna Sornicola's "Thomas Frank in the Neapolitan environment' (11-14) is a historical survey of Frank's career in Naples—from his days as a teaching assistant in English atthe Neapolitan Istituto Universitario...

Second language acquisition and the critical period hypothesis Ed. by David Birdsong (review)

478 LANGUAGE, VOLUME 76, NUMBER 2 (2000) Second language acquisition and the critical period hypothesis. Ed. by David Birdsong. (Second language acquisition research: Theoretical and methodological issues 3.) Mahwah, NJ: Lawrence Erlbaum, 1999. Pp. x, 191. The third in a series on theoretical and methodological issues in second language acquisition (SLA) research, this volume was inspired by the 1996 Association Internationale de Linguistique Appliquée symposium, 'New perspectives on the critical period for SLA'. The editor notes in his introductory chapter (1-18) that several versions of the critical period hypothesis (CPH) are represented in the book, allowing a broad perspective on the issue. In the six chapters that follow, international contributors to the volume are evenly divided in the discussion for and against critical periods in SLA. Diversifying the volume are the range of disciplines that take up the issue and the variety of evidence put forth, including but not limited to morphological, syntactic, and phonological data. The three chapters following the introduction present data from SLA studies that support the CPH. Starting from a neurophysiological approach, Christine M. Weber-Fox and Helen T. Neville (23-36) present the hypothesis that cerebral subsystems for semantics and grammar are differentially affected by critical periods (CPs). The authors' incorporation of both behavioral and electrophysiological research methods provides compelling evidence for this hypothesis . Tames R. Hurford and Simon Kirby (39-62) describe simulations that suggest that evolutionary processes contribute to a CP and discuss the implications for SLA briefly. Lynn Eubank and Kevin R. Gregg (65-93) bring a thorough linguistic theory analysis of the CPH to the volume. Asserting that CPHs in adult SLA demand refinement, the authors demonstrate ways that this refinement can come from linguistic theory. Also discussed in this chapter are fundamental distinctions of critical and/or sensitive periods and the role of physiological evidence for CPs in SLA. Three remaining chapters provide counter explanations that also fit the facts of SLA. James E. Flege (101-27) examines the discontinuity predicted by CPH vs. linear function in second language pronunciation and age of arrival. One view offered is that second language phonological production is limited by accuracy in first language perception. Theo Bongaerts (133-55) reports on three studies that he and his colleagues performed which attempted to address the concern that ultimate attainment studies focus on advanced learners. This chapter suggests that motivation , access, and training in perception and production may contribute to high levels of phonological attainment. The identification of native-like late learners of English and French from Dutch-speaking backgrounds supports this suggestion. In the final chapter (161-78), Ellen Bialystok and Kenji Hakuta challenge the assumption of causality between age and level of attainment. They explore results that fail to support the CPH in both the linguistic and cognitive evidence, concluding that there is reason to accept a null hypothesis contradicting the CPH. The 'younger equals better' hypothesis for SLA remains under advisement. In this regard the virtue of the contributions presented here is that they offer a broad scope for future research. Researchers, graduate students, and teachers will find this volume a useful equilibration of the issues. [Daniel O. Jackson , University of Pennsylvania.] The virtues of language: History in language , linguistics and texts. Ed. by Dieter Stein and Rosanna Sornicola. Amsterdam: John Benjamins, 1998. Pp. viii, 232. This collection of thirteen essays is dedicated to the memory of Thomas Frank (1925-1990), who held the Chair ofthe History ofEnglish at the University of Naples from 1982 until his death. The first essay, E. F. Konrad Koerner's revised obituary article (originally published in Historiographia Ling üistica 17.421-26 [1990]), summarizes the honorée's many accomplishments over a long and distinguished career (3-10). It contains his bibliography from 1953-1996, which includes a number of studies in the history of linguistics such as a monograph on Bishop Tohn Wilkins's (1714-1792) Essay towards a real character and a philosophical language of 1668 (Guida: Naples, 1979). Rosanna Sornicola's "Thomas Frank in the Neapolitan environment' (11-14) is a historical survey of Frank's career in Naples—from his days as a teaching assistant in English atthe Neapolitan Istituto Universitario...

A Complex-Systems Approach to Organizations

The physical sciences have developed new theories of nonlinear behavior of complex systems. Defining characteristics of complex systems include (a) being composed of many variables that interact strongly to determine system behavior, (b) sensitivity to initial conditions, and (c) stability across time. Two complex-system concepts, phase spaces and attractors, provide insight into the evolution of system behavior and make prediction of future behavior possible. It is proposed that complex-systems research has application to the study of organizations and social behavior. Organizational attractors exist and seem to be both sensitive to initial conditions and stable. The discussion of concepts from complex systems, and their application to organizations, provides insight into how organizational research should be conducted. If organizations are assumed to exhibit nonlinear behavior, more historical, longitudinal, and qualitative research methods should be used to provide context-specific descriptions of organizational behavior.

On hyperbolic discounting and uncertain hazard rates

The value of a future reward should be discounted where there is a risk that the reward will not be realized. If the risk manifests itself at a known, constant hazard rate, a riskneutral recipient ...