Combining probability values from independent permutation tests: a discrete analog of Fisher's classical method

Permutation tests are based on all possible arrangements of observed data sets. Consequently, such tests yield exact probability values obtained from discrete probability distributions. An exact nondirectional method to combine independent probability values that obey discrete probability distributions is introduced. The exact method is the discrete analog to Fisher's classical method for combining probability values from independent continuous probability distributions. If the combination of probability values includes even one probability value that obeys a sparse discrete probability distribution, then Fisher's classical method may be grossly inadequate.     

Development of key-pecking, pause, and ambulation during extended exposure to a fixed-interval schedule of reinforcement

Six pigeons key-pecked under a fixed-interval (FI) 3-min schedule of food presentation. Each pigeon was studied for 200 daily sessions with 15 intervals per session (3,000 total food presentations). Analyses included the examination of latency to first peck (pause), mean rate of key pecking, and ambulation. Characterizations of stable performance were assessed across measures of behavior and evaluated using commonly employed stability criteria. Stability of response rate and pause was identified better by assessments that evaluated variability and trend, rather than just variability. Between-subject differences in rate of acquisition and terminal values of steady-state performance of pause were observed, and stable pause durations took longer to develop than did stable key-pecking rates. Relative variability in response rate and pause duration decreased as the means increased. A temporally organized pattern of key-pecking (the so-called FI scallop) developed within 50 sessions of exposure to the schedule. Overall ambulation decreased during the early sessions of exposure and further analyses showed greater rates of ambulation during the pause than after it for 4 of the 6 pigeons. Performance under the FI 3-min schedule developed relatively slowly, and key-pecking, pause, and ambulation developed at different rates.     

An investigation of adult attachment and coping with exam-related stress

Students differ in how they cope with and manage stress associated with university life. This study investigates associations between adult attachment and coping strategies for exam-related stress. Fifty-seven students at a university in the north of England completed online questionnaires to assess attachment anxiety and avoidance, helpful and unhelpful coping strategies, and positive and negative affect. We found that students who were more avoidant in their attachment relationships were less likely to report using helpful problem-focused and emotion-focused strategies to cope with their exams. We also found that students who were more anxious in their attachment relationships reported using more dysfunctional coping strategies. We discuss the implications of the findings for university pastoral care and academic support systems.     

On the development and mechanics of delayed matching-to-sample performance

Despite its frequent use to assess effects of environmental and pharmacological variables on short-term memory, little is known about the development of delayed matching-to-sample (DMTS) performance. This study was designed to examine the dimensions and dynamics of DMTS performance development over a long period of exposure to provide a more secure foundation for assessing stability in future research. Six pigeons were exposed to a DMTS task with variable delays for 300 sessions (i.e., 18,000 total trials; 3,600 trials per retention interval). Percent-correct and log-d measures used to quantify the development of conditional stimulus control under the procedure generally and at each of five retention intervals (0, 2, 4, 8 and 16-s) individually revealed that high levels of accuracy developed relatively quickly under the shorter retention intervals, but increases in accuracy under the longer retention intervals sometimes were not observed until 100-150 sessions had passed, with some still increasing at Session 300. Analyses of errors suggested that retention intervals induced biases by shifting control from the sample stimulus to control by position, something that was predicted by observed response biases during initial training. These results suggest that although it may require a great deal of exposure to DMTS prior to obtaining asymptotic steady state, quantification of model parameters may help predict trends when extended exposure is not feasible.     

“[No] Doctor but My Master”: Health Reform and Antislavery Rhetoric in Harriet Jacobs’s Incidents in the Life of a Slave Girl

This essay examines Harriet Jacobs’s Incidents in the Life of a Slave Girl (1861) in light of new archival findings on the medical practices of Dr. James Norcom (Dr. Flint in the narrative). While critics have sharply defined the feminist politics of Jacobs’s sexual victimization and resistance, they have overlooked her medical experience in slavery and her participation in reform after escape. I argue that Jacobs uses the rhetoric of a woman-led health reform movement underway during the 1850s to persuade her readers to end slavery. This essay reconstructs both contexts, revealing that Jacobs links enslaved women’s physical and sexual vulnerability with her female readers’ fears of male doctors’ threats to modesty and of their standard bleed-and-purge treatments. Jacobs illustrates that slavery damages women’s health as much as heroic medicine, and thus merits the political activism of her readers. Specifically, Jacobs dramatizes her conflicts with the rapacious physician-master at moments that are crucial to women’s health: marriage, pregnancy, childbirth, and motherhood. Ultimately, this essay advances a new understanding of the role of health reform in social change: it galvanized other movements such as women’s rights and abolition, particularly around issues of bodily autonomy for women and African Americans.     

Rhetorics of Health Citizenship: Exploring Vernacular Critiques of Government’s Role in Supporting Healthy Living

This article explores how older adults negotiate and partially counter normative expectations of “health citizenship” that stress individual responsibility for maintaining health and preventing health problems. Based on interviews with 55 participants in Canada and the U.K. about what healthy living means to them in their everyday lives, we examine how the dominant discourse of personal responsibility in participants’ responses is counterpointed by a more muted, yet significant, alternative critical perspective on the relative roles and responsibilities of government and citizens in making healthy living possible. Drawing on Hauser’s (1999) concept of vernacular rhetoric along with recent theories of environmental citizenship, we analyze how participants exercise their civic-political judgment by using a logic of dissociation to argue that what government says about the importance of healthy living is incompatible with what government does to support citizens’ abilities to eat healthily and live actively. By deploying this technique of argumentation to address structural-political-economic dimensions of healthy living, participants enact, in modest ways, an alternative, critical-collective mode of health citizenship that complicates and, at least partially, disrupts neoliberal constructions of the individually responsible, “good” health citizen.     

The Role of Optimism,Social Constraints,Coping, and Cognitive Processing in Psychosocial Adjustment Among Breast Cancer Survivors

The social-cognitive processing model suggests that a socially constrained environment may impede adjustment to a chronic illness. The present study primarily investigated the mediating psychological pathways through which social constraints on cancer-related disclosure, low optimism, disengagement-oriented coping, and brooding could be associated with low levels of psychosocial adjustment. One hundred twenty-five female breast cancer survivors participated in a cross-sectional study. Path analysis was used to examine the proposed model. Low optimism, increased social constraints, and higher levels of brooding appeared to be risk factors for poor psychosocial adjustment to breast cancer. Disengagement-oriented coping and brooding partially mediated the relationship between social constraints and adjustment. Brooding totally mediated the relationship between disengagement-oriented coping and adjustment. The current findings provide support for the value of the social-cognitive processing model among breast cancer survivors. The mapping of psychological pathways of adjustment to breast cancer may have useful clinical implications for better adjustment outcomes.     

Outliers and Influential Observations in Exponential Random Graph Models

We discuss measuring and detecting influential observations and outliers in the context of exponential family random graph (ERG) models for social networks. We focus on the level of the nodes of the network and consider those nodes whose removal would result in changes to the model as extreme or “central” with respect to the structural features that “matter”. We construe removal in terms of two case-deletion strategies: the tie-variables of an actor are assumed to be unobserved, or the node is removed resulting in the induced subgraph. We define the difference in inferred model resulting from case deletion from the perspective of information theory and difference in estimates, in both the natural and mean-value parameterisation, representing varying degrees of approximation. We arrive at several measures of influence and propose the use of two that do not require refitting of the model and lend themselves to routine application in the ERGM fitting procedure. MCMC p values are obtained for testing how extreme each node is with respect to the network structure. The influence measures are applied to two well-known data sets to illustrate the information they provide. From a network perspective, the proposed statistics offer an indication of which actors are most distinctive in the network structure, in terms of not abiding by the structural norms present across other actors.