Children's Friends and Behavioral Similarity in Two Social Contexts

The general purpose of this study was to examine similarity between friends with respect to behavior. The specific goals were to consider; 1) different sources of evaluation (peer ratings and direct observations); 2) different social contexts (classroom and play group); and 3) different subtypes of aggressive behavior (proactive and reactive aggression). In the first phase of the study, sociometric assessments and peer evaluations of behavior were conducted in the school setting with third-grade boys and girls (n - 268). In the second phase, a subsample of boys participated in a series of play group sessions (n = 66). Direct observations and peer ratings of children's behavior were conducted in those sessions. Results showed in both social contexts a tendency towards similarity among friends, especially with respect to aggressive behavior. Separate analyses for subtypes of aggressive behavior revealed that the similarity hypothesis applied for proactive aggression but not for reactive aggression.     

Microarrays as a tool to investigate the biology of aging: a retrospective and a look to the future

The use of microarrays as a tool to investigate fundamental biological questions has become ubiquitous over the past several years. Microarrays are becoming as common as the polymerase chain reaction or any of the other tools in the molecular biologist's armory. Unlike experiments involving other tools, however, the design and analysis of microarray experiments present some unique problems to molecular biologists, problems with which statisticians have long been familiar. In this overview of microarrays and aging-related research, we will review selected highlights of microarray studies that have been carried out to study aging to date, as well as discuss some of the potential problems that routinely arise during these types of experiments, especially in the context of aging.     

如何造就非破坏性创新？

众所周知，埃德蒙·菲尔普斯的专长是微观经济学，而且他从来没有在商学院教过课，尽管如此，他在2006年赢得诺贝尔经济学奖的研究成果不仅能给当今的商业教育带来新的启示，也会对基本的商业行为产生巨大影响。     

Nonparametric Survival Estimation when Death is Reported with Delay

In disease registries there can be a delay between death of asubject and the reporting of this death to the data analyst.If researchers use the Kaplan-Meier estimator and implicitlyassumed that subjects who have yet to have death reported arestill alive, i.e. are censored at the time of analysis, the Kaplan-Meierestimator is typically inconsistent. Assuming censoring is independentof failure, we provide a simple estimator that is consistentand asymptotically efficient. We also provide estimates of theasymptotic variance of our estimator and simulations that demonstratethe favorable performance of these estimators. Finally, we demonstrateour methods by analyzing AIDS survival data. This analysis underscoresthe pitfalls of not accounting for delay when estimating thesurvival distribution and suggests a significant reduction inbias by using our estimator.     

Travel Broadens the Mind

The onset of locomotion heralds one of the major life transitions in early development and involves a pervasive set of changes in perception, spatial cognition, and social and emotional development. Through a synthesis of published and hitherto unpublished findings, gathered from a number of converging research designs and methods, this article provides a comprehensive review and reanalysis of the consequences of self‐produced locomotor experience. Specifically, we focus on the role of locomotor experience in changes in social and emotional development, referential gestural communication, wariness of heights, the perception of self‐motion, distance perception, spatial search, and spatial coding strategies. Our analysis reveals new insights into the specific processes by which locomotor experience brings about psychological changes. We elaborate these processes and provide new predictions about previously unsuspected links between locomotor experience and psychological function. The research we describe is relevant to our broad understanding of the developmental process, particularly as it pertains to developmental transitions. Although acknowledging the role of genetically mediated developmental changes, our viewpoint is a transactional one in which a single acquisition, in this case the onset of locomotion, sets in motion a family of experiences and processes that in turn mobilize both broad‐based and context‐specific psychological reorganizations. We conclude that, in infancy, the onset of locomotor experience brings about widespread consequences, and after infancy, can be responsible for an enduring role in development by maintaining and updating existing skills.     

The Limited Role of Formal Statistical Inference in Scientific Inference

ABSTRACT

Such is the grip of formal methods of statistical inference—that is, frequentist methods for generalizing from sample to population in enumerative studies—in the drawing of scientific inferences that the two are routinely deemed equivalent in the social, management, and biomedical sciences. This, despite the fact that legitimate employment of said methods is difficult to implement on practical grounds alone. But supposing the adoption of these procedures were simple does not get us far; crucially, methods of formal statistical inference are ill-suited to the analysis of much scientific data. Even findings from the claimed gold standard for examination by the latter, randomized controlled trials, can be problematic.

Scientific inference is a far broader concept than statistical inference. Its authority derives from the accumulation, over an extensive period of time, of both theoretical and empirical knowledge that has won the (provisional) acceptance of the scholarly community. A major focus of scientific inference can be viewed as the pursuit of significant sameness, meaning replicable and empirically generalizable results among phenomena. Regrettably, the obsession with users of statistical inference to report significant differences in data sets actively thwarts cumulative knowledge development.

The manifold problems surrounding the implementation and usefulness of formal methods of statistical inference in advancing science do not speak well of much teaching in methods/statistics classes. Serious reflection on statistics' role in producing viable knowledge is needed. Commendably, the American Statistical Association is committed to addressing this challenge, as further witnessed in this special online, open access issue of The American Statistician.     

Cultural and Status Differences in Intergroup Conflict Resolution: A Longitudinal Study of a Middle East Dialogue Group in the United States

Supporters of the contact hypothesis have arguedthat positive intergroup contact is facilitated whenparticipants have equal status with one another.However, the exact dimensions of equal status are often unclear, having been defined variously as equaloccupational status, having close friends of anotherrace, or having equal roles in the contact situation.This paper argues that cultural differences between groups must be taken into account, particularlywhen intergroup contact occurs in formal conflictresolution exercises. Non-Western participants will beat a disadvantage when attempting to find common ground with Western participants in conflictresolution exercises based on Western culturalpractices. Based on a 6-year participant observationstudy of a Palestinian-Jewish dialogue group, this paper argues that familiarity and expertise in usingthe culture-based rules of interaction play an importantbut often subtle role in intergroup conflict resolution.Participants must have some basic equality in their ability to function within thedominant culture.     

A hierarchical theory of occupational segregation and wage discrimination

Becker's model of discrimination is extended to the case where men exhibit distastes for working under female managers. The distribution of women in the resulting occupational hierarchy depends on the number of women in lower occupations, the wages of male workers in lower occupations, and male distastes for female management. Thus, there exists an occupational sorting function, related to wages, that determines the occupational distribution of women. We integrate this sorting function into a standard wage equation to derive a new decomposition of male-female wage differentials and apply it to a sample of insurance industry workers from the 1988 CPS.     

Quality Control for Scientific Research: Addressing Reproducibility,Responsiveness, and Relevance

ABSTRACT

Efforts to address a reproducibility crisis have generated several valid proposals for improving the quality of scientific research. We argue there is also need to address the separate but related issues of relevance and responsiveness. To address relevance, researchers must produce what decision makers actually need to inform investments and public policy—that is, the probability that a claim is true or the probability distribution of an effect size given the data. The term responsiveness refers to the irregularity and delay in which issues about the quality of research are brought to light. Instead of relying on the good fortune that some motivated researchers will periodically conduct efforts to reveal potential shortcomings of published research, we could establish a continuous quality-control process for scientific research itself. Quality metrics could be designed through the application of this statistical process control for the research enterprise. We argue that one quality control metric—the probability that a research hypothesis is true—is required to address at least relevance and may also be part of the solution for improving responsiveness and reproducibility. This article proposes a “straw man” solution which could be the basis of implementing these improvements. As part of this solution, we propose one way to “bootstrap” priors. The processes required for improving reproducibility and relevance can also be part of a comprehensive statistical quality control for science itself by making continuously monitored metrics about the scientific performance of a field of research.