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Main clause phenomena (MCPs) are syntactic constructions that occur predominantly or exclusively in main clauses. I propose a processing explanation for MCPs. Sentence processing is easiest at the beginning of the sentence (requiring less search); this follows naturally from widely held assumptions about sentence processing. Because of this, a wider variety of constructions can be allowed at the beginning of the sentence without overwhelming the sentence‐processing mechanism. Unlike pragmatic and grammatical accounts of MCPs, the processing account predicts avoidance of MCPs in non‐initial main clauses (non‐initial coordinate clauses and premodified clauses). A corpus study supports these predictions, but it is somewhat inconclusive. A further corpus study examines another type of syntactic construction, premodifying adjunct phrases (“openers”); the prediction here is that less common types of opener will be especially avoided in non‐initial contexts. The prediction is confirmed, supporting the processing view of rare constructions.  相似文献   
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Cancellation tests are commonly used in the clinical assessment of visuospatial function, but there has been little study of task characteristics influencing performance. This study was designed to assess factors which affect cancellation performance. Sixteen healthy subjects sequentially performed four random-array letter cancellation tasks. The forms contained 50 and 100 stimuli and target:distractor (T/D) ratios of 1:4 and 1:9 with target letter “A” and randomly selected letter distractors. The primary performance measure was calculated as the number of correctly cancelled targets divided by the time to complete the task, corrected for accuracy. This measure revealed a strong effect of T/D ratio (p< .0001), with performance adversely affected by higher proportion of distractors. There was no effect of stimulus number. This suggests that T/D ratio should be considered in cancellation test design and interpretation.  相似文献   
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Public goods theories highlight an incentive system that rewards ‘free riding’ on the contributions of early contributors toward collective actions. However, because such theories focus on creation of the good, they may underestimate returns that accrue to early contributors subsequent to the good's realization. The concept of formative investment is introduced here to describe the extent to which organizations help to create public goods such as interorganizational linkages like participatory federations. Data from the CEOs of 48 organizations involved in a participatory federation were used to assess how an organization's level of formative investment is related to later patterns of dependency and interaction among federation members. Findings suggest that from a long‐term perspective, and for goods that involve communication and interaction, the incentive structure may not be so favorable for free riders. To the extent that organizations with high formative investment have the capability to envision the future and communicate that vision to potential federation partners, they may be able to both reduce free riding and secure for themselves advantageous positions in the subsequent network of relations.  相似文献   
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The token economy has been the primary model for the behavioral management of inpatient populations. However, this basically operant approach seldom emphasizes the development of cognitive-coping skills to help patients more effectively manage stressors that result in hospitalization. The Therapeutic Contract Program (TCP) is described as an inpatient-treatment strategy that is designed to help foster such cognitive-coping and self-control skills. While external structure is provided by components of this program, subprograms of the TCP have as their goal the development of internally-attributed coping skills and self-perceptions of competence. This preliminary report describes the structure of the TCP, as well as planned and in-progress measures of program participation and treatment outcome.  相似文献   
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