Matching methods for selection of subjects for follow-up

This work examines ways to make the best use of limited resources when selecting individuals to follow up in a longitudinal study estimating causal effects. In the setting under consideration, covariate information is available for all individuals but outcomes have not yet been collected and may be expensive to gather, and thus only a subset of the comparison subjects will be followed. Expressions in Rubin and Thomas (1996, 2000) show the benefits that can be obtained, in terms of reduced bias and variance of the estimated treatment effect, of selecting comparison individuals well-matched to those in the treated group, as compared to a random sample of comparison individuals. We primarily consider non-experimental settings but also consider implications for randomized trials. The methods are illustrated using data from the Johns Hopkins University Baltimore Prevention Program, which included data collection from age 6 to young adulthood of participants in an evaluation of two early elementary-school based universal prevention programs.     

The testing effect in free recall is associated with enhanced organizational processes

In two experiments with categorized lists, we asked whether the testing effect in free recall is related to enhancements in organizational processing. During a first phase in Experiment 1, subjects studied one list over eight consecutive trials, they studied another list six times while taking two interspersed recall tests, and they learned a third list in four alternating study and test trials. On a test 2 days later, recall was directly related to the number of tests and inversely related to the number of study trials. In addition, increased testing enhanced both the number of categories accessed and the number of items recalled from within those categories. One measure of organization also increased with the number of tests. In a second experiment, different groups of subjects studied a list either once or twice before a final criterial test, or they studied the list once and took an initial recall test before the final test. Prior testing again enhanced recall, relative to studying on the final test a day later, and also improved category clustering. The results suggest that the benefit of testing in free recall learning arises because testing creates retrieval schemas that guide recall.     

Conditional reasoning,frequency of counterexamples,and the effect of response modality

Geiger and Oberauer (2007) found that when asked to reason with conditionals, people are very sensitive to information about the relative frequency of exceptions to conditional rules and quite insensitive to the relative number of disabling conditions. They asked participants to rate their degree of certainty in a conclusion. In the following studies, we investigated the possibility that this kind of response encourages a more probabilistic mode of processing compared with the usual dichotomous response. In Study 1, participants were given a variant of the problems used by Geiger and Oberauer with either the samescaled response format or a dichotomouscategorical response. The results with the scaled response were identical to those of Geiger and Oberauer. However, the results with the categorical response presented a very different profile. In Study 2, we presented similar problems using only frequency information, followed by a set of abstract conditional reasoning problems. The participants who performed better on the abstract problems showed a significantly different response profile than those who did worse on the abstract problems in the categorical response condition. No such difference was observed in the scaled response condition. These results show that response modality strongly affects the way in which information is processed in otherwise identical inferential problems and they are consistent with the idea that scaled responses promote a probabilistic mode of processing.     

Ephemeral Mechanisms and Historical Explanation

While much of the recent literature on mechanisms has emphasized the superiority of mechanisms and mechanistic explanation over laws and nomological explanation, paradigmatic mechanisms—e.g., clocks or synapses—actually exhibit a great deal of stability in their behavior. And while mechanisms of this kind are certainly of great importance, there are many events that do not occur as a consequence of the operation of stable mechanisms. Events of natural and human history are often the consequence of causal processes that are ephemeral and capricious. In this paper I shall argue that, notwithstanding their ephemeral nature, these processes deserve to be called mechanisms. Ephemeral mechanisms share important characteristics with their more stable cousins, and these shared characteristics will help us to understand connections between scientific and historical explanation.     

Adaptive Memory: Identifying the Proximate Roots of the Survival Processing Advantage

The current study examined the role of item-specific, relational, and elaborative processing on adaptive memory. Younger and older adults received the standard survival processing, a survival-short, or a pleasantness processing instruction. The survival-short condition was specifically included to lead to fewer possibilities to engage in elaborative processing. Furthermore, half of the presented words were categorized words to boost relational processing. Younger adults demonstrated the typical survival recall advantage in that standard survival processing instructions resulted in superior free recall performance than that of the survival-short and the pleasantness processing groups. Among older adults, no mnemonic benefit of standard survival processing relative to the survival-short or pleasantness processing groups was found. Furthermore, reducing the probability of elaborative processing (i.e., through the survival-short processing instructions) abolished the survival recall advantage. Our results thus provide further evidence for the role of item-specific, relational, and elaborative processing in the survival processing advantage.     

Colour fluctuations in grapheme‐colour synaesthesia: The effect of clinical and non‐clinical mood changes

Synaesthesia is a condition that gives rise to unusual secondary sensations (e.g., colours are perceived when listening to music). These unusual sensations tend to be reported as being stable throughout adulthood (e.g., Simner & Logie, 2007, Neurocase, 13, 358) and the consistency of these experiences over time is taken as the behavioural hallmark of genuineness. Our study looked at the influence of mood states on synaesthetic colours. In Experiment 1, we recruited grapheme‐colour synaesthetes (who experience colours from letters/digits) and elicited their synaesthetic colours, as well as their mood and depression states, in two different testing sessions. In each session, participants completed the PANAS‐X (Watson & Clark, 1999) and the BDI‐II (Beck, Steer, & Brown, 1996, Manual for Beck Depression Inventory‐II), and chose their synaesthetic colours for letters A‐Z from an interactive colour palette. We found that negative mood significantly decreased the luminance of synaesthetic colours. In Experiment 2, we showed that synaesthetic colours were also less luminant for synaesthetes with anxiety disorder, versus those without. Additional evidence suggests that colour saturation, too, may inversely correlate with depressive symptoms. These results show that fluctuations in mood within both a normal and clinical range influence synaesthetic colours over time. This has implications for our understanding about the longitudinal stability of synaesthetic experiences, and of how mood may interact with the visual (imagery) systems.     

A “Native Ministry” for God's “Step Children”? The Evolution of Missional Policy toward the Zulu in the Anglican Diocese of Natal,South Africa: 1904–1917

This article examines the evolution of the Anglican missionary policy and the evangelization of the Zulu in the Diocese of Natal in South Africa during the early 20th century. These processes rested on colonial power in the form of what Edward Said 1 conceptualized as Orientalism. Orientalism defined and ordered relations of domination and subordination wherein the English missionaries, considering themselves as superior, justify their actions as imparting what they saw as civil and religious benefits on the Zulu, whom they regarded as not possessing them. Contemptuous settler attitudes toward missionary work and their relations with the Zulu also undermined missionary work in Natal. The evolution of missionary policy along racial lines developed from the Orientalist worldview as well as on account of relations that developed in the colony.